JP3210915B2 - Direct spread receiver - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a DS-CDMA (Direct Sequence Code) using a pilot channel.
The present invention relates to a direct-spread receiver used for a Division Multiple Access system.

[0002]

2. Description of the Related Art As a DS-CDMA system, a CDMA cellular telephone system (TIA) standardized in North America.
IS95). In this system, in a downlink, a pilot symbol is inserted into a pilot channel and transmitted, and a receiving side detects a carrier phase based on a received signal of the pilot channel and performs synchronous detection. FIG. 10 is a diagram illustrating a downlink configuration in the DS-CDMA system. 81 is a base station, 8
2 is a slave station. FIG. 11 is a schematic configuration diagram of a transmission device of a base station in a DS-CDMA system. FIG.
In the code multiplexing unit 91 shown in FIG. 9A, the transmission data 1 to N of the communication channels of the users 1 to N and the data set to all 1s for the pilot channel are combined with the orthogonal code generator 9.
5 are respectively assigned and code-multiplexed, and are directly spread by being multiplied by a PN signal from a PN generator 96 in a multiplier 92, and a reference frequency of a reference frequency oscillator 97 is output in a multiplier 93. The signal (carrier) is multiplied (modulated) by the transmission antenna 9
4 is transmitted.

FIG. 11 (b) shows a block configuration for generating transmission data n of user n which is input to code multiplexing section 91 of FIG. 11 (a). To the transmission information n of the user n, a cyclic code (Cyclic Code) conversion unit 101 adds a redundant code (redundant bit for error detection) in block units. The slave station knows the reception quality of the transmitted data by decoding the corresponding error detection code. The output of the error detection coding unit is added with a predetermined number of 0 bits in the encoder tail adding unit 102 and output to the convolutional coding unit 103. The convolutional encoder 103 performs convolutional encoding, which is cleared at the end of one frame, and performs symbol repetition.
4 is output. In symbol repetition section 104,
When the information transfer rate is low, the same symbol is repeatedly output to make the transmission rate constant. The output of symbol repetition section 104 is subjected to rearrangement of bit strings in block interleaving section 105 in order to enhance the ability to correct burst errors, and outputs transmission data n.

FIG. 12 is a schematic configuration diagram of a receiving device of a slave station in a DS-CDMA system. Receiving antenna 1
The signal received by 10 is multiplied by a sine wave reference frequency signal of reference frequency oscillator 112 in multiplier 111 to be converted into a baseband reception signal. DS-C
As a feature of the demodulator of the DMA system, a Rake reception method is adopted. Since the signal transmitted from the base station reaches the receiving antenna 110 through a plurality of paths,
The received signal is a signal obtained by combining a plurality of signals having different amplitudes, carrier phases, and delay times. In the Rake reception method, a baseband reception signal is despread, separated into reception signals of paths 1 to K, and subjected to maximum ratio combination (Rake combination) to form one impulse response. C / N characteristics are improved.

[0005] The baseband received signal is output to a rake receiving section 121 and a searcher section 122. The baseband received signal is input to _K fingers 118 _{1 to} 118 K in Rake receiving section 121.
Each of the fingers 118 _{1 to} 118 _K is a demodulator for the _{first to K-} th paths, respectively. In the illustrated example, signals of up to K paths can be received. Each finger 118 _{1 -1}
18 _K have the same configuration.

[0006] A baseband received signal is multiplied by a multiplier 113.
Is multiplied by the PN code output from the PN generator 114 to obtain PN synchronization.
The signal is multiplied by the orthogonal code of the communication channel of the slave station (hereinafter referred to as “user”) output from the orthogonal code generator 117, and the integrator 116 integrates the received signal of the communication channel of the user over one symbol period. Is despread. Fingers 118 ₁ to 1
From 18 _K , the received signals obtained by despreading the communication channels of the users on the corresponding paths 1 to _K are output to the combining circuit 119.

Here, a timing signal for each of the paths 1 to K is supplied to the PN generator 114 and the orthogonal code generator 117 from a control unit 129 in the searcher unit 122 for estimating an impulse response. As a result, the PN generator 114 and the orthogonal code generator 117
The PN code and the orthogonal code synchronized with the PN code and the orthogonal code of the corresponding paths 1 to K are output.

In searcher section 122, the baseband received signal is passed through multiplier 123 to PN generator 12.
4 is multiplied by the PN code output from the P.4, and is multiplied by the orthogonal code of the pilot channel output from the orthogonal code generator 126 in the multiplier 125 to separate the pilot channel received signal. Next, the integrator 127
Represents a received signal amplitude of a baseband of a pilot channel in a certain path k and a phase (carrier phase) with respect to a reference frequency signal through a filter 128 which integrates one symbol and further performs averaging for a plurality of symbols. The reference signal W (k) is generated and the control unit 12
9 is output. W (k) is a complex number, and k = 1 to K. As paths 1 to K, the path with the larger power is K
Are selected.

In the control unit 129, the PN generator 12
The timing of the PN generator 124 is controlled so that the PN code 4 is code-synchronized with the received signal, and the timing of the orthogonal code generator 126 is controlled so that the orthogonal code of the orthogonal code generator 126 is code-synchronized with the received signal. Control unit 12
Reference numeral 9 divides the time to generate K reference signals W (k) for K fingers. Also, by dividing the time, Rak
PN of K fingers 118 ₁ - 118 _K of e receiver 121
A timing signal is output to generator 114 and orthogonal code generator 117.

In the synthesizing circuit 119, each finger 1
18 ₁ signal communication channels of a user from - 118 _K on the basis of the reference signal W (k) obtained from the received signal of the pilot channel of each path 1 to K, a communication channel of the user in the respective paths 1 to K Synchronous detection is performed by removing the phase offset of the received signal.
e Combined. The rake-combined received signal is decoded by the decoding unit 120, and desired data of the communication channel of the own station is output.

As described above, by estimating the impulse response of each path k using the despread received signal of the pilot channel on which known data is transmitted, the phase offset of the received signal of each path k is calculated. Has been removed. Although not shown, the two multipliers 111 shown in FIG.
Are also multiplied by a quadrature reference frequency signal orthogonal to the reference frequency signal, and become a two-series baseband reception signal (usually represented by a complex number) in phase and orthogonal to the reference frequency signal. The subsequent processes are individually performed on the two sequences, and the combining circuit 119 synchronously detects the two sequences as an in-phase component and a quadrature component with respect to the phase of the reference frequency signal (carrier).

Generally, DS-CDMA is used for high-speed data transmission.
When the system is used, the chip rate naturally increases as the data rate increases. As the chip rate increases, the amount of interference due to multipath increases. When the number of multipaths increases, deterioration of transmission performance can no longer be prevented by the Rake reception method. When a signal obtained by combining the arriving waves of paths 1 to K with a time delay is received, when the arriving wave of a certain path k is despread, the arriving waves of the other paths with a time delay become interference signals. Therefore, an impulse response of one path k includes an interference wave component generated by a cross-correlation with an incoming wave of another path. Therefore, if the impulse responses of the paths 1 to K are rake-combined, the transmission performance deteriorates.

As a first conventional technique for eliminating such multipath interference, there is an interference cancellation technique.
For example, Wada et al., "B5-140 DS-CDMA"
A study of a multi-user multi-stage interference canceller in a system ", IEICE Society Conference (19988.9). Such an interference canceller (hereinafter referred to as prior art) is disclosed in the present application. The person has filed an application as Japanese Patent Application No. 10-236777.

First, an accurate impulse response is estimated using a pilot channel or the like. K paths having a large amplitude are selected, and the value is set to W (k) (k = 1 to K). The path P having the maximum amplitude value is selected. 1
The rake reception data is input to the first-stage interference canceller, and the output data of the previous-stage interference canceller is input to the second and subsequent interference cancellers. Furthermore, an interference replica for each user is generated using the spreading code and W (k) for each path other than the maximum amplitude path P. By subtracting interference replicas of all users from the received signal, despreading is performed on path P, and data for all users is detected. That is, W (k) is estimated in advance, and information on radio wave propagation is fixed after the estimation.

As a second conventional technique for canceling an interference signal by a different method, Sawahashi et al., "DS-CDMA Coherent Multistage Interference Canceller Using Channel Estimation and Successive Update Using Pilot and Data Symbols", IEICE Tech. 96 (354), IEICE (1996-11) RCS 96-100, p. 9-16
Some are known. This is W-CDMA
(Broadband CDMA) system.

This W-CDMA is a DS-CDMA system having a pilot symbol section in a frame. The interference is canceled one by one from the user having the largest power. Here, the channel estimation / interference generation unit of a certain user performs Rake combining of signals despread for each of a plurality of multipaths, performs data determination, and estimates a spread signal of each multipath from the determination data. An interference replica is generated, and the interference replica is canceled from the received despread signal and input to the above-described channel estimation / interference generation unit.

Further, the above-described interference cancellation is performed in each stage i of a multi-stage (multi-stage configuration).
For the user k, the interference replica at the i-stage for the user having a higher power than the user k and the interference replica at the i-1 stage for the other user having the lower power are removed. , The interference replica other than each path is removed, the impulse response in each path is estimated using pilot symbols, and despreading is performed based on the value. The signals despread in each path are rake-combined. After the combining, an interference replica is generated based on the decoded data and the estimated impulse response.

The above-described interference canceller needs to obtain reliable reception data in advance. In order to improve the ability to cancel interference, it is necessary to increase the certainty of the received data. However, in the prior art, since the received data at the stage of digital demodulation is used in order to simplify the configuration, there is a limit in increasing the certainty of the received data. Conventionally, IS-95
In, the transmission information is subjected to convolutional coding, and the receiving apparatus outputs the received information which has been subjected to Viterbi decoding and error correction. However, since the scale of the processing unit until the reception information is obtained becomes very large and the processing time becomes long, generating an interference replica from the reception information has not been considered. However, it has been found that the use of the error-corrected received information dramatically improves the interference canceling ability. Further, even when using the received data at the stage of digital demodulation, the interference canceller has a problem in processing time and power consumption. In particular, in a multi-stage interference canceller in which error characteristics are improved by cascading the interference cancellers in multiple stages, the processing time and power consumption increase according to the number of stages.

The present invention has been made in order to solve the above-mentioned problems. Before describing the present invention, however, the functions of the interference canceller will be specifically described by describing the above-mentioned prior art. Keep it. FIG. 13 is a basic block configuration diagram of the prior art. A code-multiplexed channel sharing one PN code corresponds to one communication channel (1
User) and one pilot channel. On the other hand, FIG. 12 shows a code-multiplexed communication channel (user) sharing one PN code.
Is a plural case, so the assumption is slightly different.
The receiving unit will be described with reference to FIG.

In this basic configuration, the impulse response is estimated, the reference signal W (k) representing the impulse response is fixed, and the output data DR is detected by the rake receiving unit 121. In addition, the power maximum path detector 131
Selects the path P having the maximum power based on the reference signal W (k). In the interference canceller 133, R
The data output from the ake receiving unit 121 is used as initial reception data to generate a signal before performing synchronous detection and despreading on a path other than the path P where the power is maximum, and based on known data of a pilot channel. Then, in the paths other than the path P having the maximum power, the signals of the pilot channels before despreading are generated, these are used as interference replicas, and the interference replica is subtracted from the received signal to obtain the path P having the maximum power. , The data is detected again by performing despreading and synchronous detection again. In this manner, the bit error rate is improved by removing the interference that is a cause of the deterioration of the received signal quality.

In the searcher section 122 shown in FIG.
K paths with large power obtained by despreading the pilot channel received signal are selected, and the reference signal W (k) (k = 1) is used as the value of the impulse response of each of the paths 1 to K.
To K) are output. The power maximum path detector 131 shown in FIG. 14 selects the path P having the maximum power from the reference signal W (k), and outputs the value of P to the interference canceller 133.

FIG. 16 is an explanatory diagram of the operation of the interference canceller 133 shown in FIG. The signal transmitted from the base station 1 passes through a plurality of paths and is received as a combined signal of signals having different delay times. The upper diagram shows an impulse response by multipath. A path P having the maximum power is selected, and a baseband received signal before performing synchronous detection and despreading in another path is virtually generated based on the detection data and pilot channel data, and is subtracted. The received signal is subjected to despreading in the path P having the maximum power, and data in which an interference signal is canceled as shown in the lower part is detected.

The path P having the maximum power has a small ratio including an interference signal, and the paths other than the path P are estimated to be mainly interference signals. Then, the Rake receiving unit 12
The data DR that is likely to be output from the communication channel 1 of one user is used as an initial value, and a signal before the synchronous detection and despreading is generated from the signal DR by performing reverse signal processing. At the same time, it generates a previous signal of the pilot channel to be despread based on a known data D _p of the pilot channel. In this way, interference replicas in paths 1 to K excluding path P are generated.
Then, when all the interference replicas of the paths 1 to K excluding the path P are subtracted from the baseband reception signal, the baseband reception signal is almost only the path P.

Therefore, the interference canceller 133 has
Output data DR one communication channel that is output from the ake receiver 121, and, using known data D _p of the pilot channel, without path P of maximum power K
Generate an interference replica of one path. Then, despreading is performed again on the path P for the baseband reception signal obtained by removing the interference replica from the baseband reception signal. In this way, it is possible to perform despreading on a baseband received signal substantially the same as when it is assumed that only an incoming wave of a single path P has been received.
As a result, reception data DC of the communication channel from which the interference signal due to the cross-correlation of the path is removed is obtained. The delay unit 132 compensates for a processing delay inside the rake receiving unit 121 and the interference canceller 133.

FIG. 14 is an internal configuration diagram of the interference canceller 133 shown in FIG. The interference replica generation unit 135 for one user generates interference replicas for K-1 paths excluding the path P for the only communication channel used by only one user. Further, the pilot channel interference replica generating unit 135 _p generates interference replicas for the K−1 paths excluding the path P for the pilot channel.

FIGS. 15A and 15B show interference replica generators 135 and 135 shown in FIG. 14, respectively.
It is an internal block diagram of p. Regarding the interference replica generation unit 141 ₁ for path 1, the data DR output from the rake reception unit 121 is output to the multiplier 138 by the path 1
Is multiplied by the reference signal W ₁ (1)
The carrier phase and amplitude of the path 1 are returned to the signal before the synchronous detection, which has the signal point phase and amplitude added. Next, the PN for pass 1 is
The code PN ₁ (1) is further multiplied by the orthogonal code WS ₁ (1) for one user's path 1 in the multiplier 140 and spread, thereby despreading with a time delay of path 1. The signal is returned to the baseband received signal before the transmission, and an interference replica of path 1 is generated. Same configuration as that of the interference replica generation unit 141 ₁ for the path 1 is located 1 K-piece with the exception of the path P, these K-1 pieces of signals are added by the adder 142, the output signal path P Excluded are the output signals of the interference replicas of paths 1 to K.

Here, W ₁ (k) (k = _{1 to} K, k = P
Is a reference signal output from the control unit 129 shown in FIG. 12, and PN ₁ (k) (except for k = _{1 to} K, k = P) is a PN generator 114 of the finger 118 _k shown in FIG. Output the PN code and the orthogonal code WS ₁ (k) (k = 1 to
K, k = P) are the fingers 118 shown in FIG.
_This is based on the orthogonal code of one user output from the _k orthogonal code generator 117. However, as shown in FIG. 13, the baseband reception signal is delayed by the delay unit 132,
The time delay is adjusted in consideration of the processing delay in the rake receiving unit 121 and the processing delay inside the interference canceller 133. W ₁ (k), PN ₁ (k), and WS ₁ (k) are provided with the same delay unit as the delay unit 132 for the outputs of the control unit 129, PN generator 114, and orthogonal code generator 117, respectively. It can be made by providing.

As shown in FIG. 15B, in the interference replica generator 135 _p for the pilot channel, the known data D _p of the pilot channel is added to the multiplier 13.
At 8, the signal is multiplied by the reference signal W ₁ (1) for path 1 to become a signal having the signal point phase and amplitude given the carrier phase and amplitude of path 1.
Next, PN ₁ (1) which is a PN code for path 1 in multiplier 139, and orthogonal code WS for pilot channel path 1 in multiplier 140
_By being multiplied by ₁ (p, 1) and spreading, respectively, the baseband reception signal having the time delay of path 1 before being despread is returned to generate an interference replica of path 1. Figure 15 similarly to (a), the same configuration as the interference replica generation unit 141 ₁ for the path 1 is located 1 K-piece with the exception of path P, these K-1 pieces of signal adders 1
42, the output signal becomes the output signal of the interference replica of the paths 1 to K excluding the path P.

Here, W ₁ (k) (k = _{1 to} K, k = P
Is a reference signal output from the control unit 129 shown in FIG. 12, and PN ₁ (k) (except for k = _{1 to} K, k = P) is a PN generator 124 of the searcher unit 122 shown in FIG. PN code (PN generator 1 with finger 118 _k )
14), and the orthogonal code WS ₁
(P, k) (except k = 1 to K, k = P) is based on the orthogonal code of the pilot channel output from the orthogonal code generator 126 of the searcher unit 122 shown in FIG. However, a time delay is provided to compensate for the processing delay in the Rake receiving unit 121, and the time delay is adjusted in consideration of the processing delay inside the interference canceller 133. W ₁ (k), PN ₁ (k), WS ₁ (p, k)
Can be produced by providing a delay unit similar to the delay unit 132 in each of the outputs of the control unit 129, the PN generator 124, and the orthogonal code generator 126 described above.

Returning to FIG. 14, the description will be continued. In the adder 136, the output signal of the interference replica 135 is subtracted from the delayed baseband reception signal, and the result is input to the despreading unit 137 for the path P. The despreading unit 137 for this path P has the same configuration as the finger part of the path P in the finger parts 118 _{1 to} 118 _K shown in FIG. That is, the reference signal W for the path P
₁ (P), a PN code for the path P, PN ₁ (P),
And one user's orthogonal code WS for path P
_{Using 1} (P), the baseband received signal from which the interference replica has been deleted is subjected to despreading with respect to the path P, and data is determined.

This output data is data of one user whose reception quality has been improved by eliminating interference due to cross-correlation. The above-described reference signal W ₁ (P), PN code PN
₁ (P) and one user's orthogonal code WS ₁ (P)
The reference signal W of the path excluding the path P described above
₁ (k), the PN code PN ₁ (k), and the orthogonal code WS ₁ (k) of one user have a time delay in order to compensate for the processing delay in the Rake receiving unit 121 and the interference The time delay is adjusted in consideration of the processing delay inside the canceller 133.

FIG. 17 shows codes sharing one PN code.
The multiplexed channels are N-user communication channels and
Prior art block consisting of one pilot channel
It is a block diagram. And interference capacities corresponding to multiple users
The interference canceller 151 of the 1st to Mth stages₁~ 15
1_MAre connected in cascade. In this specific example
Can be used for multiple paths from multiple users 1-N.
Operating the canceller to remove interference,
It works the canceller and seems more certain
Data is detected. First-stage interference canceller 151
₁Is the data DR output from the Rake receiving unit 146.
(1) to input DR (N) as likely data
Together with the known data D of the pilot channel _pTo
Input, interference signal canceled, more likely
Data DC (1, 1) to DC (1, N) are output.

[0033] The second and subsequent stages, the output data from the preceding stage interference canceller with becomes the input data of the interference canceller of the next stage, also known data D _p of pilot channels is input. Each of the interference cancellers 151 _{1 to} 151 _{M at} any stage has a maximum power path detector 131 (FIG. 1).
The same path P output from 3) is selected as the maximum power path. Note that among the interference cancellers at each stage, 1 to (M
-1) For the interference cancellers 151 _{1 to} 151 _{M−1 at the first} stage, it is necessary to output data of users 1 to N including data of the own station (for example, user 1). That is, 1
(M-1) th stage interference canceller 151 _{1 to} 151 _M-1
Requires a despreading unit for user 1 to user N.

The above-described direct spread receiving apparatus has been described on the premise of the CDMA cellular telephone system (TIA-IS95). However, this direct spread receiver is WC
It is also applicable in a DMA system. W-CDM
In the A system, communication channels of a plurality of users are code-multiplexed, and a pilot symbol common to the plurality of communication channels is inserted in a certain time interval,
The reference signal W (k) is output by estimating the impulse response based on the pilot symbol.

In W-CDMA, the section of the user communication channel and the section of the pilot channel are temporally different, but if the multipath of the pilot channel enters the section of the user communication channel, Will cause interference due to multipath cross-correlation on the user communication channel. Therefore, by using the pilot channel interference replica generating unit 135p shown in FIG. 14, it is possible to remove the interference caused by the pilot channel. However, an interference replica of the pilot channel is generated even in a section of the pilot channel where no received signal of the user communication channel exists. If the interference replica component in the section of the pilot channel is large, it may become a noise component, which may lower the transmission quality. Accordingly, the output of the pilot channel interference replica generator 135p shown in FIG. 14 is output to the adder 136 via a switch (not shown). The switch unit is controlled by the control unit 129 to supply the interference replica of the pilot channel to the adder 136 only in the section of the user communication channel.

[0036]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a direct spread receiving apparatus which dramatically improves the quality of received information. It is another object of the present invention to provide a direct spread receiver that reduces the power consumption of an interference canceller while maintaining the quality of received information.

[0037]

According to the present invention, in the first aspect, transmission data is generated based on data in which transmission information is error-correction-coded, and the transmission data is directly spread. A direct spread receiving apparatus for receiving a direct spread signal, comprising: an initial data output unit, an error correction unit, and an interference canceling unit, wherein the initial data output unit includes an initial receive data based on the direct spread receive signal. The error correction means performs error correction encoding after decoding the error correction code based on the initial received data, the interference cancellation means, based on the output of the error correction means, A replica of the interference signal included in the direct spread received signal is generated, and the replica is subtracted from the direct spread received signal to reduce the influence of the interference signal. And it outputs the data. Therefore, interference cancellation is performed using the initial reception data that has been error-corrected and the likelihood is increased, so that the quality of received information can be significantly improved. The interference canceling means may be a single-stage interference canceller or a multi-stage interference canceller. For example, a convolutional code can be used as the error correction code, and Viterbi decoding can be performed for the decoding.

According to the second aspect of the present invention, the transmission data is generated based on the data in which the transmission information is subjected to the error correction coding, and the direct spread reception for receiving the direct spread signal in which the transmission data is directly spread is received. An apparatus, comprising an initial data output unit, an error correction unit, a plurality of series of interference canceling units, and a combination determination unit, wherein the initial data output unit transmits the direct spread signal with an antenna corresponding to the plurality of series. Receiving, outputting the initial received data common to the respective sequences based on the direct spread received signals of the respective sequences, and the error correction means decoded the error correction code based on the initial received data. Later, error correction coding is performed, and the interference canceling means for each sequence performs direct spreading of each sequence based on the output of the error correcting means. Generating a replica of the interference signal included in the received signal, subtracting the replica from the direct spread received signal of each of the sequences, outputting a despread signal of each of the sequences reduced in the influence of the interference signal, The combination determining means decodes a signal obtained by combining the despread signals of the respective streams and outputs received data. Therefore, the quality of the received information is further improved as compared with the first aspect of the invention due to the diversity effect due to the multi-system receiver configuration.

According to the third aspect of the present invention, transmission data is generated based on data in which transmission information is error-correction coded, and a direct spread signal for receiving a direct spread signal in which the transmission data is directly spread is received. An apparatus comprising: an initial data output unit; a plurality of stages of interference cancellers; and at least one stage error correction unit provided corresponding to a stage immediately before the last stage of the interference canceller. Outputs the initial received data based on the direct spread received signal, the first stage interference canceller generates a replica of the interference signal included in the direct spread received signal based on the initial received data, The replica is subtracted from the direct spread received signal to output first-stage reception data in which the influence of the interference signal is reduced, and the error correction means of each stage outputs After performing error correction coding based on the output of the interference canceller of the stage, error correction coding is performed, and the interference cancellers of the second and subsequent stages perform the direct spreading based on the output of the error correction means of the preceding stage. A replica of the interference signal included in the reception signal is generated, and the replica is subtracted from the direct spread reception signal to output reception data of the stage in which the influence of the interference signal is reduced. Therefore, since the interference canceling means has a multi-stage configuration, the quality of the received information is further improved as compared with the first aspect of the present invention.

According to the fourth aspect of the present invention, there is provided a direct-spread receiving apparatus for generating transmission data based on data in which transmission information is subjected to error correction coding, and receiving a direct-spread signal in which the transmission data is directly spread. An apparatus, comprising: an initial data output unit, a plurality of stages of interference cancellers in a plurality of stages, a plurality of stages of combining determining units, and at least one stage error provided corresponding to a stage immediately before the last stage of the combining determining unit. Correction means, the initial data output means receives the direct spread signal with the antenna corresponding to the plurality of sequences, based on the direct spread received signal of each sequence, the initial received data for each of the sequences And the interference canceller of each sequence of the first stage performs direct spreading of each sequence based on initial reception data for each sequence. A replica of the interference signal included in the received signal is generated, and the replica is subtracted from the direct spread reception signal of each of the sequences to obtain a despread signal of each sequence of the first stage in which the influence of the interference signal is reduced. The first stage of the synthesis determining means decodes a signal obtained by synthesizing the despread signals of the respective series of the first stage and outputs first stage received data. Performs error correction coding after decoding the error correction code based on the output of the synthesis determination means of the stage, and the interference cancellers of the respective series in the second and subsequent stages are provided by the error correction unit of the preceding stage. Generating a replica of the interference signal included in the direct-sequence reception signal of each sequence based on the output, subtracting the replica from the direct-sequence reception signal of each sequence to obtain the interference signal Outputs the despread signal of each sequence of the stage in which the influence of the stage has been reduced, and the combining determination means of the second and subsequent stages decodes a signal obtained by combining the despread signals of the sequences of the stage. It outputs the received data of the stage. Claim 5
In the invention described in the above, transmission data is generated based on data in which transmission information is subjected to error correction coding, and a direct spread receiving apparatus for receiving a direct spread signal obtained by directly spreading the transmission data, Data output means, a plurality of stages of interference cancellers of a plurality of stages, a plurality of stages of combination determination means, and at least one stage error correction means provided corresponding to the stage immediately before the last stage of the combination determination means, The initial data output unit receives the direct spread signal with an antenna corresponding to the plurality of sequences, and outputs common initial reception data to each of the sequences based on the direct spread reception signals of each of the sequences. The interference cancellers of each sequence of one stage are included in the direct sequence reception signals of the respective sequences based on initial reception data common to the respective sequences. Generating a replica of the interference signal, subtracting the replica from the direct sequence reception signal of each of the sequences, and outputting a despread signal of each sequence of the first stage in which the influence of the interference signal is reduced; The combination determining means of the stage decodes a signal obtained by combining the despread signals of the respective sequences of the first stage and outputs received data of the first stage, and the error correction means of each stage outputs the received data of the stage. The error correction coding is performed after decoding the error correction code based on the output of the combination determination unit, and the interference cancellers of the respective sequences in the second and subsequent stages are configured based on the output of the error correction unit in the previous stage. A replica of the interference signal included in the direct sequence reception signal of each sequence is generated, and the replica is subtracted from the direct sequence reception signal of each sequence to reduce the influence of the interference signal. And outputs a despread signal of each sequence of the stage, and the combining determination means of the second and subsequent stages decodes a signal obtained by synthesizing the despread signal of each sequence of the stage, and outputs the received data of the stage. Is output. Accordingly, since the receiver has a plurality of systems and the interference canceling means has a multi-stage structure, the quality of the received information is further improved as compared with the first aspect of the present invention.

In the invention according to claim 6, transmission data is generated based on data in which transmission information is subjected to block error detection coding, and a direct spreading signal for receiving a direct spreading signal in which the transmission data is directly spread is received. A receiving device,
Initial data output means, interference cancellation means, error detection means, and output selection means, the initial data output means outputs initial reception data based on a direct spread reception signal, the interference cancellation means, Based on the initial received data, generate a replica of the interference signal included in the direct spread received signal, subtract the replica from the direct spread received signal, output the received data reduced the influence of the interference signal, The error detection means, by decoding an error detection code based on the initial received data, detects an error in units of the block error detection coded data block, the output selection means,
In accordance with the detection result of the error detecting means, the operation of the interference canceling means in the block subsequent to the block targeted for error detection by the error detecting means is controlled, and the error detecting means detects the error. In the block subsequent to the target block, reception information based on any one of the initial reception data and the output of the interference cancellation unit is selected. Therefore, since the operation failure of the interference canceling means is controlled according to the detection result of the error detecting means, the processing time of the receiving processing is reduced and the power consumption of the receiving apparatus is reduced while maintaining the quality of the received data at a predetermined level. Can be achieved. The transmission information may be subjected to block error correction coding after block error detection coding, or may be subjected to block error detection coding before block error correction coding. As the block error detection code, for example, a cyclic code can be used. The interference canceling means may be a single-stage interference canceller or a multi-stage interference canceller.

According to the seventh aspect of the present invention, transmission data is generated based on data in which transmission information is subjected to block error detection coding, and a direct spreading signal for receiving a direct spreading signal in which the transmission data is directly spread is received. A receiving device,
Initial data output means, interference cancellation means for a plurality of sequences,
A combination determining unit, an error detecting unit, and an output selecting unit, wherein the initial data output unit receives the direct spread signal with an antenna corresponding to the plurality of sequences, and based on the direct spread reception signal of each sequence. Output the common initial reception data for each sequence, the interference cancellation means of each sequence, based on the initial reception data,
A replica of the interference signal included in the direct sequence reception signal of each of the sequences is generated, and the replica is subtracted from the direct sequence reception signal of each of the sequences to obtain an inverse of each of the sequences in which the influence of the interference signal is reduced. A spread signal, the combining determining means decodes a signal obtained by combining the despread signals of the respective sequences and outputs received data, and the error detecting means outputs an error detecting code based on the initial received data. Decoding, the error is detected in units of the block of the block error detection coded data, and the output selection means detects the error in the error detection means according to the detection result of the error detection means. Controlling the operation of the interference cancellation means in the block subsequent to the target block; In is for selection in the block subsequent to the block was an error detected, the received information based on one of the output of the initial received data and the synthetic judgment means. Therefore, the quality of the received information is further improved as compared with the invention according to claim 6 due to the diversity effect due to the configuration of the receivers of a plurality of systems.

According to the invention described in claim 8, transmission data is generated based on data in which transmission information is coded by block error detection, and a direct spreading signal for receiving a direct spreading signal in which the transmission data is directly spread is received. A receiving device,
An initial data output unit, a plurality of stages of interference cancellers, at least one stage error detection unit provided corresponding to a stage immediately before the last stage of the interference canceller, and an output selection unit, wherein the initial data output unit is Outputting the initial received data based on the direct spread received signal, the first stage interference canceller generates a replica of the interference signal included in the direct spread received signal based on the initial received data, By subtracting the replica from the spread reception signal and outputting reception data in which the influence of the interference signal is reduced, the interference cancellers of the second and subsequent stages are configured to output the direct spread reception signal based on the output of the previous stage interference canceller. Generating a replica of the interference signal included in, subtracting the replica from the direct spread received signal, the effect of the interference signal is reduced The received data of the stage is output, and the error detecting means of each stage, along with the cascade operation of the interference cancellers of the plurality of stages, detects an error detection code based on the received data output from the combining determination unit of the stage. By performing the decoding, an error is detected in units of the block of the block error detection encoded data, and the output selection unit determines the error of each of the stages according to an error detection result of the error detection unit of each of the stages. In the block subsequent to the block for which the error detection is performed by the error detection unit, the number of operating stages of the plurality of stages of interference cancellers is controlled and reception information based on any one of the reception data of each stage is output. Is what you do. Therefore, since the interference canceling means has a multi-stage configuration, the quality of the received information is further improved as compared with the invention described in claim 6. Even in a multi-stage configuration, the number of operation stages of the interference canceling means is controlled in accordance with the detection result of the error detection means. Power consumption can be reduced.

According to the ninth aspect of the present invention, transmission data is generated based on data in which transmission information is subjected to block error detection coding, and a direct spreading signal for receiving a direct spreading signal in which the transmission data is directly spread is received. A receiving device,
An initial data output unit, a plurality of stages of interference cancellers in a plurality of stages, a plurality of stages of combining determination units, at least one stage error detection unit provided corresponding to a stage immediately before the last stage of the combining determination unit, and output selection Means, the initial data output means receives the direct spread signal with the antenna corresponding to the plurality of sequences, based on the direct spread received signal of each sequence, the initial received data for each of the sequences Output, the interference canceller of each sequence of the first stage, based on the initial received data for each sequence, to generate a replica of the interference signal included in the direct spread received signal of each sequence, Subtracting the replica from the direct spread received signal of each sequence,
A first-stage despread signal having a reduced influence of the interference signal is output, and the combining determination means of the first stage is a signal obtained by combining the first-stage despread signals. And outputs the received data of the first stage, and the interference cancellers of the respective sequences of the second and subsequent stages are included in the direct spread reception signals of the respective sequences based on the output of the combining determination means of the preceding stage. Generating a replica of the interference signal, subtracting the replica from the direct spread received signal of each of the series, and outputs a despread signal of each series of the stage in which the influence of the interference signal is reduced, The combination determination means of the second and subsequent stages decodes a signal obtained by combining the despread signals of the respective streams of the stage and outputs received data of the stage, and the error detection means of each stage comprises a plurality of stages. of With the cascade operation of Wataru canceller,
By decoding an error detection code based on the received data output by the combination determination unit of the stage, an error is detected in units of the block error detection encoded data block, and the output selection unit is Controlling the number of operating stages of the multi-stage interference canceller in the block subsequent to the block targeted for error detection by the error detecting unit of each stage according to an error detection result of the error detecting unit of each stage. And selecting reception information based on any one of the reception data of each stage.
Further, in the invention according to claim 10, transmission data is generated based on data in which transmission information has been subjected to block error detection coding, and a direct spread reception for receiving a direct spread signal in which the transmission data is directly spread. Device, an initial data output means, a plurality of stages of a plurality of series of interference cancellers,
A plurality of synthesis determination means, at least one error detection means provided corresponding to a stage immediately before the last stage of the synthesis determination means, and an output selection means; Receiving the direct spread signal with an antenna corresponding to the sequence, outputting, based on the direct spread reception signal of each sequence, initial reception data common to each of the sequences, the interference of each sequence of the first stage; The canceller generates a replica of the interference signal included in the direct sequence reception signal of each sequence based on the initial reception data common to each sequence, and generates the replica from the direct sequence reception signal of each sequence. Subtract,
A first-stage despread signal having a reduced influence of the interference signal is output, and the combining determination means of the first stage is a signal obtained by combining the first-stage despread signals. And outputs the received data of the first stage, and the interference cancellers of the respective sequences of the second and subsequent stages are included in the direct spread reception signals of the respective sequences based on the output of the combining determination means of the preceding stage. Generating a replica of the interference signal, subtracting the replica from the direct spread received signal of each of the series, and outputs a despread signal of each series of the stage in which the influence of the interference signal is reduced, The combination determination means of the second and subsequent stages decodes a signal obtained by combining the despread signals of the respective streams of the stage and outputs received data of the stage, and the error detection means of each stage comprises a plurality of stages. of With the cascade operation of Wataru canceller,
By decoding an error detection code based on the received data output by the combination determination unit of the stage, an error is detected in units of the block error detection encoded data block, and the output selection unit is Controlling the number of operating stages of the multi-stage interference canceller in the block subsequent to the block targeted for error detection by the error detecting unit of each stage according to an error detection result of the error detecting unit of each stage. And selecting reception information based on any one of the reception data of each stage.
Therefore, since the receiver has a plurality of systems and the interference canceling means has a multi-stage structure, the quality of the received information is further improved as compared with the present invention. Even in a multi-stage configuration, the number of operation stages of the interference canceling means is controlled in accordance with the detection result of the error detection means. Power consumption can be reduced.

According to the eleventh aspect of the present invention, transmission data is generated based on data obtained by performing block error detection coding on transmission information, and a direct spreading signal for receiving a direct spreading signal in which the transmission data is directly spread is received. A receiver, comprising: an initial data output unit, a plurality of stages of interference cancellers, an initial error detection unit, at least one stage error detection unit provided corresponding to a stage immediately before the last stage of the interference canceller, and an output selection unit. Means, the initial data output means outputs initial received data based on a direct spread received signal, and the first stage interference canceller is included in the direct spread received signal based on the initial received data. Generating a replica of the interference signal to be received, subtracting the replica from the direct-spread reception signal, the reception data reduced the influence of the interference signal The interference canceller of the second and subsequent stages generates a replica of the interference signal included in the direct spread received signal based on the output of the interference canceller of the previous stage, and generates the replica from the direct spread received signal. Subtracting the block error detection code by outputting the reception data of the stage where the influence of the interference signal is reduced, and decoding the error detection code based on the initial reception data. The error detection means of each stage, along with the cascade operation of the interference cancellers of the plurality of stages, based on the received data output by the interference canceller of the stage, By decoding the error detection code, an error is detected for each block of the block error detection encoded data, and the output selection is performed. The means, following the error detection result of the initial error detection means and the error detection means of each stage, the block subsequent to the block subjected to error detection by the initial error detection means and the error detection means of each stage In the block, non-operation of the plurality of stages of interference cancellers and the number of operation stages are controlled, and reception information based on any one of the initial reception data and the reception data of each stage is selected. Therefore, in addition to controlling the number of operation stages of the interference canceller in the invention according to claim 8, it is possible to stop the operations of all the interference cancellers, further reduce the processing time of the reception processing, and reduce the power consumption of the reception device Can be reduced.

According to the twelfth aspect of the present invention, transmission data is generated based on data in which transmission information is subjected to block error detection coding, and a direct spreading signal for receiving a direct spreading signal in which the transmission data is directly spread is received. A receiving device, comprising: an initial data output unit; a plurality of stages of interference cancellers in a plurality of stages; a plurality of stages of combining determining means; an initial error detecting unit; and at least one stage corresponding to a stage immediately before the last stage of the combining determining unit. Error detection means, and output selection means, wherein the initial data output means receives the direct spread signal with an antenna corresponding to the plurality of sequences, and based on a direct spread reception signal of each sequence, a common Outputting an initial reception data, and the interference canceller of each of the first-stage series is configured to perform the above-mentioned interference cancellation based on the initial reception data common to each of the series. Of generating a replica of the interference signal included in the direct spread received signal sequence, by subtracting said replica from direct spread reception signals of the respective sequence,
A first-stage despread signal having a reduced influence of the interference signal is output, and the combining determination means of the first stage is a signal obtained by combining the first-stage despread signals. And outputs the received data of the first stage, and the interference cancellers of the respective sequences in the second and subsequent stages convert the direct-sequence reception signals of the respective sequences based on the output of the combining determination means in the preceding stage. Generate a replica of the interference signal included, subtract the replica from the direct spread received signal of the respective sequence, and output a despread signal of each sequence of the stage where the influence of the interference signal is reduced, The combining determination means of the second and subsequent stages decodes a signal obtained by combining the despread signals of the respective sequences of the stage and outputs received data of the stage, and the initial error detecting means comprises: By decoding the error detection code based on the initial reception data common to the series, an error is detected in units of the block of the block error detection encoded data, and the error detection means of each stage includes Along with the cascade operation of the interference canceller of the stage, by decoding an error detection code based on the received data output from the combination determination means of the stage, the block of the block error detection coded data is used as a unit. An error is detected, and the output selection unit determines whether an error is to be detected by the initial error detection unit and the error detection unit of each stage in accordance with an error detection result of the initial error detection unit and the error detection unit of each stage. In the block subsequent to the block, the operation of the multiple-stage interference canceller is controlled and the number of operation stages is controlled. And selects the received information based on one of said received data phases received data and each stage. Therefore, claim 9,
In addition to the control of the number of operation stages of the interference canceller according to the tenth aspect, it becomes possible to stop the operations of all the interference cancellers, and to further reduce the processing time of the reception processing and reduce the power consumption of the reception device. be able to.

[0047]

FIG. 1 is a block diagram for explaining a first embodiment of the present invention. As an example, a case where the code multiplex channel includes one user and one pilot channel is shown. CDMA of IS-95
In the system, as shown in FIG. 11 (b), processing such as error detection coding, convolutional coding, and block interleaving is performed at the base station. It is assumed that only encoding is performed. When the processing is performed together with other processing, a processing block corresponding to the processing block on the transmitting side may be added to the receiver configuration of the slave station.

In the figure, reference numeral 1 denotes a rake receiving unit. For example, the rake receiving unit 121 shown in FIG. 13 can be used. 2 is an intermediate error processing unit, 3 and 7 are Viterbi decoding units, 4 is a convolutional coding unit, 5 is a direct spread reception signal dropped to baseband according to the processing delay in the intermediate error processing unit 2 and the interference canceller 6. Is a delay unit for delaying the baseband reception signal. Reference numeral 6 denotes an interference canceller. As an example, the interference canceller 133 shown in FIG. 13 can be used.

The initial received data output from the rake receiving unit 1 is subjected to error correction processing in the intermediate error processing unit 2 and is output to the interference canceller 6 as initial received data with increased reliability. The interference canceller 6 generates a replica of the interference signal included in the baseband reception signal output from the delay unit 5, subtracts the replica from the baseband reception signal, and obtains the Viterbi received data with reduced influence of the interference signal. Output to the decoding unit 3. This Viterbi decoding unit 3
Then, error correction of received data is performed, and received information is output.

The intermediate error processing section 2 of this embodiment obtains error-corrected reception information from the initial reception data in the Viterbi decoding section 3 and then performs convolutional coding again in the convolutional coding section 4 to obtain an error. Initial reception data is generated based on the corrected reception information. As a result, it is possible to output very likely initial reception data to the interference canceller 6, so that the capability of the interference canceller 6 can be enhanced. The output of the interference canceller 6 is supplied to the Viterbi decoding unit 7 so that the reception information DC matching the transmission information is obtained.
Is obtained. Note that the above-described Rake receiving unit 1 is for providing reliable initial reception data necessary for interference cancellation, and is replaced with, for example,
A despreading unit that despreads the baseband directly-spread received signal and decodes the despread output of the path P having the largest power among them may be used.

FIG. 2 is a block diagram for explaining a second embodiment of the present invention. In the figure, the same parts as those in FIG. 11 is an intermediate error processing unit, 12 and 13 are cyclic code decoding units, and 14 is a selection / control unit. In this embodiment, after the transmission side inserts redundant bits into transmission information and performs cyclic coding,
This is based on the assumption that convolutional coding is performed. 1 is obtained by replacing the intermediate error processing unit 2 in the block diagram of FIG. The output of the Viterbi decoding unit 3 is also output to the cyclic code decoding unit 12. Here, the presence or absence of an error is detected for each block, and if no error is detected, the error flag ER is set to 0, and if an error is detected even for one bit, the error flag is set to ER = 1. Also, it outputs the reception information DR from which the redundant bits have been removed. The output of the interference canceller 6 becomes reception information DC from which redundant bits have been removed by the Viterbi decoding unit 7 and the cyclic code decoding unit 13.
The cyclic code decoding unit 13 need only remove redundant bits, but may also output an error flag CR to monitor the reception quality.

When no error is detected in a certain block (ER = 0), the selection / control section 14 outputs the reception information DR to the output data Dout in the next block.
And At the same time, in the next block, the operation of the interference canceller 6 is stopped. On the other hand, the selection / control unit 14
When an error is detected in a certain block (ER =
In 1), in the next block, interference cancellation is performed, and the reception information DC with improved reception quality is output data Do.
Output as ut.

The interference canceller 6 can be realized by a hardware circuit. By changing and controlling the number of operation stages of the interference canceller, it is possible to shorten the processing time for interference cancellation while maintaining the reception quality at a predetermined level. As a result, the power consumption of the hardware circuit of the interference canceller 6 can be reduced. Further, the interference canceller can be realized by software using a CPU or DSP and an arithmetic processing program. In this case, the processing time can be reduced while maintaining the reception quality at a predetermined level, so that the processing load on the CPU or the DSP can be reduced. In addition, the operation of the Viterbi decoding unit 7 and the like on the assumption that the interference canceller 6 is operating can be controlled to further reduce power consumption.

In the above description, the operation of the interference canceller 6 is controlled in units of one block, but the present invention is not limited to such control. For example, resume operation when the appearance percentage of blocks that detected the error stops the operation of the interference canceller 6 when it becomes less than the predetermined ratio E1, exceeds a predetermined ratio _{E 2 (E 1 <E 2} ) again You may do so. If a problem occurs in operations such as Viterbi decoding and interference canceller at the start of the operation, it is preferable to reduce the frequency of operation switching.

As described above, by controlling the operation of the interference canceller and the like according to the detection of an error in units of blocks, that is, according to the reception quality, the processing of the interference canceller and the like can be performed while maintaining the reception quality at a predetermined level. Time and power consumption can be reduced. It is also conceivable to use the reception information DC as output data for the block in which an error has been detected. However, in this case, since the baseband signal needs to be delayed by one or more data blocks in the delay unit 5, the power consumption of the buffer that realizes the delay unit 5 cannot be ignored.

FIG. 3 is a block diagram for explaining a third embodiment of the present invention. In the figure, the same parts as those in FIGS. This embodiment is based on the premise that redundant bits are inserted into transmission information on the transmission side and are directly spread after being cyclically coded, so that the intermediate error processing unit 11 in the block diagram of FIG. Is replaced by Therefore, the output of the rake receiving unit 1 is directly output to the interference canceller 6 and also output to the cyclic code decoding unit 12. The cyclic code decoding unit 12 detects the presence or absence of an error on a block-by-block basis,
Is output. The output of the interference canceller 6 is output from the reception information DC from which the redundant bits have been removed by the cyclic code decoding unit 13.
Becomes Since the error correction is not performed, the reception quality is about the same as the error rate in the related art, but the power consumption can be adaptively reduced according to the reception environment.

FIG. 4 is a schematic diagram for explaining an example of the operation of the block configuration shown in FIG. 31 is Rake
Received data output by the receiving unit 1, 32 is an output DR of the intermediate error processing unit 21, 33 is an output of the interference canceller 6, 34
Is an output DC of the cyclic code decoding unit 13, and 35 is an output data Dout of the selection / control unit 14. Initially, the interference canceller 6 is also operated. Selection / control unit 14
Has a data buffer inside.

In the first block, Dout =
DR. The operation of the interference canceller 6 is stopped for the blocks. The interference canceller 6 starts operating when a block is input. However, if ER = 0 is output after the end of the block, the interference canceller 6 stops operating and Dout = DR also in the next block. The interference canceller 6 starts operating when a block is input. However, when ER = 1 is output after the end of the block, the operation is continued.
ut = DC. When ER = 1 is output after the end of the block, the interference canceller 6 continues to operate, and Dout = DC also in the block. After the end of the block, when ER = 1 is output, the operation is continued, and Dout = DC also in the block. The interference canceller 6 stops its operation when ER = 0 is output after the end of the block, and Dout = DR in the block.

As described above, when no error is detected in a certain block in cyclic code decoding section 12, selection / control section 14 sets Rak in the next block.
The reception information based on the output of the e receiving unit 1 is set as output data. On the other hand, when an error is detected, the selection / control unit 1
4 operates the interference canceller 6 in the next block, and uses received information based on the output as output data. When the error is no longer detected, in the next block, the selection / control unit 14 appropriately delays the reception information based on the output of the rake reception unit 1 as output data and stops the operation of the interference canceller. . as a result,
Except that an erroneous block is output at the time of switching, it is possible to output received information in which no error is detected, and to adaptively determine the operation of the interference canceller according to the detection of an error in block units. Thus, power consumption can be reduced.

The block error is not recovered by the interference canceller 6, but may be corrected by another method, for example, retransmission correction (ARQ: Automatic Repeat Request). If the selection / control unit 14 does not include a buffer for the reception information of the user n, the connection between blocks will not be successful at the time of selection switching, but it is possible to cope with ARQ. Note that data in which transmission information is convolutionally encoded as shown in FIG. 1 may be regarded as transmission information according to the present embodiment. For example, a case may be used in which, after convolutional coding, redundant bits are added in block units and cyclic coding is performed. The operation control of the interference canceller 6 is not limited to one block unit. Like the block configuration of FIG. 2, for example, the operation of the interference canceller 6 is stopped when the appearance ratio of blocks that has detected the error is less than a predetermined proportion E _1, predetermined ratio E ₂ (E ₁ again <
The operation may be restarted when E ₂ ) is exceeded.

FIG. 5 is a block diagram for explaining a fourth embodiment of the present invention. In this embodiment, 2
It has a receiver of the system. To distinguish between the first and second receivers, reference numerals are appended with a or b. In the figure,
The same parts as those in FIG. 41a and 41b are receiving antennas; 42a and 42b are multipliers; 43a and 43b are reference frequency oscillators;
44b is a Rake receiving unit, 45 and 49 are synthesis determining units,
6a and 46b are delay units, 47 is an intermediate error processing unit, 48 is an interference canceller, and 50 is a termination error processing unit.

[0062] Two systems of receiving antennas are provided for diversity. For example, two receiving antennas are provided at a distance (space diversity). Or,
Two identical directional antennas are provided with different antenna orientations (angle diversity). Alternatively, antennas with different directivities are used (angle diversity). The directional characteristics and installation conditions of these antennas are
A single antenna or a combination of two or more antennas may be used.

The different receiving antennas 41a, 41
The signals received by 1b are multiplied by the sine wave reference frequency signals of reference frequency oscillators 43a and 43b in multipliers 42a and 42b, and are converted into baseband direct spread reception signals. The reference frequency oscillators 43a and 43b are
It outputs a sine wave reference frequency signal of the same frequency, and can share one reference frequency oscillator. This baseband received signal is despread in Rake receiving sections 44a and 44b, and outputs a despread signal.

The rake receiving units 44a and 44b perform the same functions as the rake receiving units 1a and 1b shown in FIG. 1, but have different output signal forms. Rake
The despread signal corresponding to the impulse response of the initial received data at the stage immediately before decoding in the receiving units 44a and 44b to obtain the initial received data is output. 2
By determining the outputs of the Rake receiving units 44a and 44b of the system by combining them in the combining determination unit 45, the initial reception data becomes more reliable. This combination determination unit 45
The combination determination is performed by a method similar to the combination determination unit 49 described below with reference to FIG.

The intermediate error processing section 47 has the configuration shown in FIGS.
Of the intermediate error processing units 2, 11 and 21 shown in FIG. When the intermediate error processing unit 2 or 11 is used,
Error-corrected received data is obtained as initial received data. When the intermediate error processing unit 11 or 21 is used, selection of output data and interference cancellers 48a, 48
8b. Two-series interference canceller 6a,
6b generates a replica of the interference signal included in the direct spread reception signal based on the initial reception data output from the intermediate error processing unit 47, and subtracts this replica from the direct spread reception signal to reduce the influence of the interference signal. And outputs the despread signal. Note that the delay units 46a and 46b
By compensating for processing delays in the receiving units 44a and 44b, the combining determination unit 45, the intermediate error processing unit 47, and the interference cancellers 6a and 6b, the output of the intermediate error processing unit 47 and the baseband This is to match the input timing with the direct spread reception signal.

The interference cancelers 48a and 48b are similar to the interference canceller 6 of FIG. 1 and the interference canceller 133 of FIG. 13 in the prior art. However, these have a built-in decoding unit for performing data determination. In this embodiment, since the data is determined by the subsequent combining determination unit 49, the interference canceller 4
8a and 48b output the despread signal at the stage immediately before determining the received data. This despread signal corresponds to the impulse response of the received data determined by the interference canceller in the related art. The combination determination unit 49
The signal obtained by combining the despread signals output from the series of interference cancellers 48a and 48b is decoded to determine received data.

Two antennas 41a and 41b for each system
Are independent. That is, they undergo different multipath fading.
For this reason, there is a high possibility that a direct spread reception signal having no output reduction due to fading fluctuation can be received from one of them, and therefore, it is resistant to fading fluctuation. In addition, what affects the noise of the two receivers is the antenna 41a,
Multiplier 42 for converting from 41b to a baseband reception signal
a, 42b, etc. If there are two receivers, the noise is independent for each receiver. Therefore, the effect of noise is 1
It is averaged compared to the system.

The interference cancellers 48a and 48b output the despread signals immediately before the received data is determined after removing the interference replica. As described above, an interference canceller is used on the basis of a baseband signal obtained by adding independent noises to received signals that have undergone independent multipath fading, and the output signals of the two systems are combined and determined. By doing so, this direct spreading receiver has better received data quality than the performance of one system of interference canceller alone. The bit error rate is generally
There is a correlation with the average Eb / No when the signal power per bit is Eb and the noise power per Hz is No, and the bit error rate decreases as Eb / No increases.
When Gaussian noise is added to the demodulator (static characteristics), the diversity effect has the effect of equivalently increasing Eb / No by 3 dB. Therefore, a similar improvement is expected in this embodiment.

The rake receiving units 44a, 44
For example, the rake receiving unit 1 shown in FIG. Each of the initial received data may be input to each of the two intermediate error processing units 47 provided for each stream, and the output may be output to the interference cancellers 48a and 48b of the corresponding stream. In this case, the intermediate error processing unit 2 shown in FIG. 1 is used as the intermediate error processing unit 47. In this case, very reliable initial reception data can be output to the interference cancellers 48a and 48b, so that the capability of the interference canceller 6 can be enhanced. Also in this embodiment, instead of the Rake receiving units 44a and 44b, for example, a despreading unit that despreads the baseband received signal and decodes the despread output of the path P having the maximum power is used. You may.

FIG. 6 is an explanatory diagram of the combination judging section 49 shown in FIG. FIG. 6A is an explanatory diagram of the synthesizing function, and FIG.
(B) is an explanatory diagram of a determination function. The in-phase component (I phase) and quadrature component (Q phase) of the despread signal output from the interference canceller 48a of the first receiver (system a) are represented by (V _1i ,
V _1q ), the in-phase and quadrature components of the despread signal output from the interference canceller 48b of the second receiver (system b) are (V _2i , V _2q ), and the in-phase and quadrature components of the composite signal are (V _2q ). _0i , V _0q ).

The combined signal is created by adding weights W _t1 and W _t2 to the despread signals from the interference cancellers 48a and 48b of the first and second receivers, respectively. That is, V _0i = V _1i * W _t1 + V _2i * W _t2 V _0q = V _1q * W _t1 + V _2q * W _t2 . Here, as the weights W _t1 and W _t2 , for example, W _t1 = (V _1i ² + V _1q ² ) / ｛(V _1i + V _2i ) ² + (V _1q
+ V _2q) ² ｝ ^1/2 W _t2 = (V _2i ² + V _2q ² ) / ｛(V _1i + V _2i ) ² + (V _1q
+ V _2q) ² ｝ ^1/2 .

Alternatively, as the weights W _t1 and W _t2 , W _t1 = (V _1i ² + V _1q ² ) ^1/2 / Ｖ (V _1i + V _2i ) ² + (V
^{_{1q + V 2q) 2} 1/2}} W t2 = (V 2i 2 + V 2q 2) 1/2 / {(V 1i + V 2i) 2 + (V
_1q + V _2q) ² ｝ ^1/2 . The value of each denominator is the length of a vector obtained by adding the despread signals output from the interference cancellers 48a and 48b of the first and second receivers. As shown in FIG. 6B, in the case of four-phase modulation, the combined signal (V
_0i , V _0q ) is decoded according to which quadrant on the IQ phase plane.

The terminal error processing section 50 performs processing corresponding to the intermediate error processing section 47. Intermediate error processing unit 47
The intermediate error processing units 2 and 1 shown in FIGS.
When 1 and 21 are used, the Viterbi decoding unit 7, the Viterbi decoding unit 7, the cyclic code decoding unit 12, and the cyclic code decoding unit 13 shown in FIGS.

FIG. 7 is a block diagram for explaining a fifth embodiment of the present invention. In this embodiment,
As an example, it is assumed that code multiplexing of N users is performed, and that the interference canceller has a multi-stage configuration and that the interference cancellers are operated in cascade in a plurality of stages. In the figure, 51 is a Rake receiving unit,
52 and 56 are intermediate error processing units, 53, 55 and 57 are delay units, 54 and 58 are interference cancellers, 59 is a termination error processing unit, 60 is an error determination / control unit, and 61 is a selection unit. R
The ake receiving unit 51 obtains initial reception data for each of the users 1 to N. For example, Rak shown in FIG.
The e receiving unit 146 can be used. Interference canceller 54, and outputs a received data interference cancellation for each user 1 to N, for example, can be used an interference canceller 151 ₁ shown in FIG. 17. The last-stage interference canceller 58 may perform interference cancellation only for the user n of the receiving apparatus.
It can be used an interference canceller 151 _M shown in.

When the intermediate error processing units 52 and 56 perform the same error correction processing as the intermediate error processing unit 2 in FIG. 1 and the intermediate error processing unit 11 in FIG. 2, Viterbi decoding is performed for each of the users 1 to N. And convolutional coding. The termination error processing unit 59 performs Viterbi decoding only on the reception data of the user n of the receiving apparatus, and
C (M, n) and outputs this as output data Dout
And The error determination / control unit 60 and the selection unit 61 are not used.

On the other hand, when the error detection processing is performed in the same manner as in the intermediate error processing section 11 in FIG. 2 and the intermediate error processing section 21 in FIG. An error flag E is detected by detecting an error in block units.
R, EC (1) are set to 1. Alternatively, the cyclic code may be decoded for each of the users 1 to N, and when a block error is detected even for one user, the error flag ER may be set to 1. In any case, the reception information of the user n of the receiving apparatus is output as DR (n) and DC (1, n). In the terminal error processing unit 59, error detection may be performed in the same manner as in the intermediate stage.

As each stage of the interference cancellers 54,..., 58 operates in cascade, the ability to cancel interference improves, and as the stage proceeds to the intermediate error processing units 52, 56,. And more likely received data D
R (n), DC (1, n), DC (2, n), ..., DC
(M, n) can be output. Here, 1 to M are the number of stages of the interference canceller. The error determination / control unit 60 includes error flags ER, EC (1),..., EC output from the intermediate error processing units 52, 56,.
, EC (M-1), and inputs the received information DR (n), DC (1),..., DC (m),
, DC (M) is selected as output data Dout. Although various selection methods are conceivable, an example will be described here.

FIG. 8 is a schematic diagram for explaining an example of the operation of the block configuration shown in FIG. Description will be made on the assumption that the number of stages is M = 2. In the figure, 61 is the received data of the Rake receiving unit 51, 62 is the received information DR (n) output from the intermediate error processing unit 52, 63 is the output of the interference canceller 54, 6
4 is the output DC (1, n) of the intermediate error processing unit 56, 65 is the output of the interference canceller 58, 66 is the termination error processing unit 59
The received information DC (M, n) 66 output from is the output data Dout output from the selector 61.

In the block, Dout = DR
(N). The operation of the interference canceller 54 is stopped for the blocks. The interference canceller 54 starts operating when a block is input, but stops operating when ER = 0 is output after the end of the block, and Dout = DR (n) also in the next block. The interference canceller 54 starts operating when a block is input. However, when ER = 1 is output after the end of the block, the operation continues, and in the block, Dout =
DC (1, n). The interference canceller 58 starts operating when a block is input, but continues to operate when ER = 1 and EC (1) = 1 are output after the end of the block. In the block, Dout = DC (M ,
n). The interference canceller 58 starts operating when a block is input.
When R = 1 and EC (1) = 0 are output, the operation stops,
In the block, Dout = DC (1, n). The interference canceller 54 starts operating when a block is input, but stops operating when ER = 0 is output after the end of the block.
ut = DR (n).

As described above, when no error is detected in a certain block in a certain intermediate error processing section, the reception information of this stage is used as output data in the next block. On the other hand, when an error is detected, in the next block, the interference canceller of the next stage is operated,
The received information at that stage is output data. When the error is no longer detected in the intermediate error processing section of the previous stage, in the next block, the reception information of the stage closest to the first stage among the stages in which the error is no longer detected is used as output data, and Stop the operation of the interference canceller. As a result, except that an erroneous block is output at the time of switching of stages, it is possible to output received information in which no error is detected, and in response to error detection in units of blocks, By adaptively determining the non-operation of the interference canceller and the number of operation stages according to the reception quality, it is possible to reduce the interference canceller processing time and power consumption.

It is to be noted that the error flag ER of the intermediate error processing section 52 is not included in the error determination / control section 60, and the reception information DR (n) output from the intermediate error processing section 52 is not included in the selection section 61. Alternatively, at least the first-stage interference canceller 54 may always be operated to select the interference-cancelled reception information. Further, in the intermediate error processing unit 52, error correction may not be performed, or the intermediate error processing unit 52 itself may be omitted.

FIG. 9 is a block diagram for explaining a sixth embodiment of the present invention. In this embodiment,
As an example, it is assumed that code multiplexing of N users is performed, and the interference canceller is configured in a multi-stage configuration, and the interference cancellers are operated in cascade in a plurality of stages. In the figure, the same parts as those in FIGS. 5 and 7 are denoted by the same reference numerals, and description thereof will be omitted. Combination judgment section 71
Is Rake that obtains initial reception data for each of users 1 to N
The outputs of the receiving units 51a and 51b are input, and users 1 to N
The combination determination is performed every time, and the initial reception data is output to the intermediate error processing unit 52. The combining determination unit 72 inputs the outputs of the interference cancellers 54a and 54b that obtain despread signals for each of the users 1 to N, performs a combining determination for each of the users 1 to N,
The first-stage reception data is output to the intermediate error processing unit 56.
The combining determination unit 73 may perform the combining determination only for the user n of the receiving device.

As in FIG. 7, as each stage of the interference canceller cascades, the ability to cancel interference is improved, and the intermediate error processing units 52, 56,.
Every time the process proceeds to step 9, more reliable reception data can be output. The error determination / control unit 60 and the selection unit 6
When 1 is used, the processing time and power consumption can be reduced by adaptively determining the number of operation stages according to the detection of an error in units of blocks. FIG.
Similarly, at least the first-stage interference canceller 54a,
54b may always be operated to select the interference-cancelled reception information. Further, in the intermediate error processing unit 52, error correction may not be performed, or the intermediate error processing unit 52 itself may be omitted.

In the above description, two receivers are used when a plurality of receivers are configured. However, the combination may be determined using a larger number of receivers. In addition, the outputs of a plurality of systems of receiving antennas are sequentially switched by a selection switch means, etc., so that at least only the receiving antenna is actually provided with a plurality of systems. Multiple streams may be multiplexed.

In the above description, the interference cancellation for canceling the interference signal of the direct spread received signal has been described. However, the interference canceller according to the present invention is not limited to the interference canceller, and may be any canceller that removes a signal that reduces the bit error rate from a received signal for a general received signal including a direct spread received signal. By replacing with a canceller, the quality of the received information can be dramatically improved.

[0086]

According to the present invention, as is apparent from the above description, interference cancellation is performed using the error-corrected initial received data, so that the quality of received information can be significantly improved. is there. Further, the present invention has an effect that the processing time and power consumption of the interference canceller can be reduced while maintaining the quality of received information.
Further, a configuration having both of the two effects described above is also possible.

[Brief description of the drawings]

FIG. 1 is a block diagram for explaining a first embodiment of the present invention.

FIG. 2 is a block diagram for explaining a second embodiment of the present invention.

FIG. 3 is a block diagram for explaining a third embodiment of the present invention.

FIG. 4 is a schematic diagram for explaining an example of the operation of the block configuration shown in FIG. 3;

FIG. 5 is a block diagram for explaining a fourth embodiment of the present invention.

FIG. 6 is an explanatory diagram of a combination determination unit shown in FIG. 5;

FIG. 7 is a block diagram illustrating a fifth embodiment of the present invention.

FIG. 8 is a schematic diagram for explaining an example of the operation of the block configuration shown in FIG. 7;

FIG. 9 is a block diagram for explaining a sixth embodiment of the present invention.

FIG. 10 is a diagram illustrating a configuration of a downlink in a DS-CDMA system.

FIG. 11 is a schematic configuration diagram of a transmission device of a base station in a DS-CDMA system.

FIG. 12 is a schematic configuration diagram of a receiving device of a slave station in the DS-CDMA system.

FIG. 13 is a basic block configuration diagram of a prior art.

FIG. 14 is an internal configuration diagram of the interference canceller shown in FIG.

15 is an internal configuration diagram of the interference replica generation unit shown in FIG.

16 is an explanatory diagram of the operation of the interference canceller shown in FIG.

FIG. 17 is a block diagram of a prior art in which a code-multiplexed channel sharing one PN code is composed of an N-user communication channel and one pilot channel.

[Explanation of symbols]

1 Rake receiving section, 2 intermediate error processing section, 3, 7 Viterbi decoding section, 4 convolutional coding section, 5 delay section, 6
Interference canceller, 11 Intermediate error processing unit, 12, 13
Cyclic code decoder, 14 selector / controller

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-2000-216703 (JP, A) JP-A-2000-269931 (JP, A) Proceedings of the 1998 IEICE Communication Society Conference, p. 390 1999 IEICE General Conference Lecture Papers, Communication 1, p. 454 (58) Field surveyed (Int. Cl. ⁷ , DB name) H04B 1/69-1/713 H04J 13/00-13/06 H04L 1/06

Claims (12)

(57) [Claims] 1. A direct-spread receiving apparatus for generating transmission data based on error-correction-coded data of transmission information and receiving a direct-spread signal obtained by directly spreading the transmission data, comprising: Means, error correction means, and interference cancellation means, wherein the initial data output means outputs initial reception data based on a direct spread reception signal, and the error correction means outputs an error based on the initial reception data. Performing error correction encoding after decoding the correction code, the interference canceling means generates a replica of the interference signal included in the direct spread received signal based on the output of the error correction means, A direct-sequence receiving apparatus, wherein the replica is subtracted from a received signal to output received data in which the influence of the interference signal is reduced. 2. A direct spread receiving apparatus for generating transmission data on the basis of data in which transmission information is subjected to error correction coding and receiving a direct spread signal obtained by directly spreading the transmission data, comprising: Means, error correction means, a plurality of series of interference canceling means, and a combination determining means, The initial data output means receives the direct spread signal with an antenna corresponding to the plurality of sequences, Outputting common initial reception data to each of the sequences based on the direct spread reception signal, the error correction unit performs error correction coding after decoding an error correction code based on the initial reception data, The interference canceling means of each sequence, based on the output of the error correction means, Generating a replica,
Subtracting the replica from the direct sequence received signal of each of the sequences, outputs a despread signal of each of the sequences in which the influence of the interference signal has been reduced, A direct-spread receiver, which decodes a signal obtained by synthesizing and outputs received data. 3. A direct-spread receiving apparatus for generating transmission data based on error-correction-coded data of transmission information and receiving a direct-spread signal obtained by directly spreading the transmission data, comprising: Means, a plurality of stages of interference cancellers, and at least one stage of error correction means provided corresponding to stages immediately before the last stage of the interference canceller, wherein the initial data output means is based on a direct spread received signal. The first stage interference canceller generates a replica of the interference signal included in the direct spread received signal based on the initial received data, and extracts the replica from the direct spread received signal. Then, the first stage reception data in which the influence of the interference signal is reduced is output, and the error correction means of each stage outputs the data of the interference canceller of the stage. Performing error correction coding after decoding the error correction code based on A direct-sequence receiving apparatus, comprising: generating a replica of the signal; subtracting the replica from the direct-sequence received signal; and outputting reception data of the stage in which the influence of the interference signal is reduced. 4. A direct-spread receiver for generating transmission data based on data in which transmission information is subjected to error correction coding and receiving a direct-spread signal obtained by directly spreading the transmission data, comprising: Means, a plurality of stages of interference cancellers of a plurality of sequences, a plurality of combining decision means, and at least one provided corresponding to a stage immediately before the last stage of the combining decision means.
Having an error correction means of a stage, the initial data output means receives the direct spreading signal with an antenna corresponding to the plurality of sequences, and for each of the sequences based on the direct spreading reception signal of each sequence. Outputting an initial reception data, the interference canceller of each sequence of the first stage, based on the initial reception data of each sequence, generates a replica of the interference signal included in the direct sequence reception signal of each sequence. Generating and subtracting the replica from the direct sequence received signal of each sequence to output a despread signal of each sequence of the first stage in which the influence of the interference signal is reduced, The means decodes a signal obtained by synthesizing the despread signals of the respective sequences of the first stage and outputs received data of the first stage, and the error correction means of each stage decodes the received data of the stage. The error correction coding is performed after decoding the error correction code based on the output of the combination determination means, and the interference cancellers of the respective sequences in the second and subsequent stages are:
Generating a replica of the interference signal included in the direct spread received signal of each of the sequences based on the output of the error correction means at the previous stage, subtracting the replica from the direct spread received signal of each of the sequences, Outputting the despread signal of each sequence of the stage in which the influence of the signal is reduced, wherein the combining determination means of the second and subsequent stages decodes a signal obtained by combining the despread signals of the respective sequences of the stage; And outputting the received data of the corresponding stage. 5. A direct-spread receiving apparatus for generating transmission data based on data in which transmission information is subjected to error correction coding and receiving a direct-spread signal obtained by directly spreading the transmission data, comprising: Means, a plurality of stages of interference cancellers of a plurality of sequences, a plurality of combining decision means, and at least one provided corresponding to a stage immediately before the last stage of the combining decision means.
Having an error correction means of a stage, wherein the initial data output means receives the direct spread signal by an antenna corresponding to the plurality of streams, and is common to the respective streams based on the direct spread reception signals of the respective streams. The first stage of the interference canceller of each series, based on the initial reception data common to each of the series, the interference canceller of the direct sequence reception signal of each of the series Generating a replica, subtracting the replica from the direct spread received signal of each of the sequences, outputting a despread signal of each of the first stages in which the influence of the interference signal is reduced, The combining determining means decodes a signal obtained by combining the despread signals of the respective series of the first stage, and outputs received data of the first stage. Performing error correction coding after decoding the error correction code based on the output of the combination determination means in the second stage, and the interference cancellers of the respective sequences in the second and subsequent stages,
Generating a replica of the interference signal included in the direct spread received signal of each of the sequences based on the output of the error correction means at the previous stage, subtracting the replica from the direct spread received signal of each of the sequences, Outputting the despread signal of each sequence of the stage in which the influence of the signal is reduced, wherein the combining determination means of the second and subsequent stages decodes a signal obtained by combining the despread signals of the respective sequences of the stage; And outputting the received data of the corresponding stage. 6. A direct-spread receiving apparatus for generating transmission data based on data in which transmission information has been subjected to block error detection coding, and receiving a direct-spread signal obtained by directly spreading the transmission data, comprising: Output means, interference cancellation means, error detection means, and output selection means, wherein the initial data output means outputs initial reception data based on a direct spread reception signal; and Based on the data, generate a replica of the interference signal included in the direct spread received signal, subtract the replica from the direct spread received signal, output the received data reduced the influence of the interference signal, the error, The detecting means decodes the error detection code based on the initial received data, thereby obtaining the block error detection encoded data. Detecting an error in units of blocks, the output selecting means, in accordance with the detection result of the error detecting means, the interference canceling means in the block subsequent to the block subjected to error detection by the error detecting means While controlling the operation failure, in the block subsequent to the block subjected to error detection by the error detection unit, the reception information based on any one of the initial reception data and the output of the interference cancellation unit A direct spread receiver. 7. A direct spread receiving apparatus for generating transmission data based on data obtained by performing block error detection coding on transmission information and receiving a direct spreading signal obtained by directly spreading the transmission data, comprising: Output means, interference cancellation means for a plurality of sequences,
A combination determining unit, an error detecting unit, and an output selecting unit, wherein the initial data output unit receives the direct spread signal with an antenna corresponding to the plurality of sequences, and based on a direct spread reception signal of each sequence. And outputting the initial received data common to each sequence, and the interference canceling means of each sequence generates a replica of the interference signal included in the direct spread received signal of each sequence based on the initial received data. Then, the replica is subtracted from the direct sequence reception signals of the respective sequences to output despread signals of the respective sequences in which the influence of the interference signal is reduced. Decoding a signal obtained by synthesizing the spread signal and outputting received data, wherein the error detecting means includes an error detection code based on the initial received data. By detecting the error in units of the block of the block error detection coded data, and the output selection unit detects the error by the error detection unit according to the detection result of the error detection unit. Controlling the operation failure of the interference canceling means in the block subsequent to the target block, the initial reception data in the block subsequent to the block targeted for error detection by the error detection means, A direct-sequence receiving device, wherein the receiving information is selected based on any one of the outputs of the combination determining means. 8. A direct spread receiving apparatus for generating transmission data based on data obtained by performing block error detection coding on transmission information and receiving a direct spread signal obtained by directly spreading the transmission data, comprising: Output means, a plurality of stages of interference cancellers, at least one stage error detection means provided corresponding to stages immediately before the last stage of the interference canceller, and output selection means, wherein the initial data output means Outputting an initial reception data based on the spread reception signal; the first stage interference canceller generates a replica of the interference signal included in the direct spread reception signal based on the initial reception data; Subtracting the replica from the signal and outputting received data in which the influence of the interference signal is reduced; A replica of the interference signal included in the direct spread received signal is generated based on the output of the interference canceller, and the replica is subtracted from the direct spread received signal to reduce the influence of the interference signal. The error detection means of each stage, by the cascade operation of the interference canceller of the plurality of stages, by decoding the error detection code based on the received data output from the combination determination means of the stage The block error detection detects an error in units of the coded data block, and the output selection means, in accordance with the error detection result of the error detection means of each stage, the error in the error detection means of each stage In the block subsequent to the block targeted for detection, the number of operating stages of the plurality of interference cancellers is controlled and the reception data of each stage is controlled. And outputs the received information based on one of, the spread receiver device directly to said. 9. A direct spread receiving apparatus for generating transmission data based on data in which transmission information has been subjected to block error detection coding and receiving a direct spreading signal obtained by directly spreading the transmission data, comprising: An output unit, a plurality of stages of interference cancellers in a plurality of stages, a plurality of stages of combining determination units, at least one stage error detecting unit provided corresponding to a stage immediately before the final stage of the combining determining unit, and an output selecting unit. Having, the initial data output means receives the direct spread signal with an antenna corresponding to the plurality of sequences, based on the direct spread received signal of each sequence, outputs the initial received data for each of the sequences The interference canceller of each sequence of the first stage, based on the initial received data for each of the sequences, a direct spread received signal of each of the sequences. Generating a replica of the interference signal included in, and subtracting the replica from the direct sequence received signal of each of the series, and outputs a despread signal of each series of the first stage in which the influence of the interference signal is reduced. The first-stage combining determination means decodes a signal obtained by combining the despread signals of the respective first-stage sequences and outputs first-stage reception data; The interference canceller of
A replica of the interference signal included in the direct spread received signal of each of the sequences is generated based on the output of the combining determination unit at the preceding stage, and the replica is subtracted from the direct spread received signal of each of the sequences to obtain the interference. Outputting a despread signal of each sequence of the stage in which the influence of the signal is reduced, wherein the combining determination means in the second and subsequent stages decodes a signal obtained by combining the despread signals of the respective sequences of the stage; The error detection means of each stage, along with the cascade operation of the interference cancellers of the plurality of stages, an error detection code based on the reception data output by the combination determination means of the stage. By performing the decoding of the above, an error is detected in units of the block of the block error detection coded data, In accordance with the detection result, in the block subsequent to the block subjected to the error detection by the error detection means in each of the stages, the number of operating stages of the plurality of stages of interference cancellers is controlled and the reception data of each stage is controlled. A direct-sequence receiving apparatus for selecting received information based on any one of them. 10. A direct-spread receiving apparatus for generating transmission data based on data in which transmission information has been subjected to block error detection coding, and receiving a direct-spread signal obtained by directly spreading the transmission data, comprising: An output unit, a plurality of stages of interference cancellers in a plurality of stages, a plurality of stages of combining determination units, at least one stage error detecting unit provided corresponding to a stage immediately before the final stage of the combining determining unit, and an output selecting unit. The initial data output means receives the direct spread signal with an antenna corresponding to the plurality of streams, and outputs initial receive data common to the respective streams based on the direct spread received signals of the respective streams. The interference canceller of each sequence in the first stage performs direct spreading reception of each sequence based on initial reception data common to each sequence. A replica of the interference signal included in the received signal is generated, and the replica is subtracted from the direct spread reception signal of each of the sequences to obtain a despread signal of each sequence of the first stage in which the influence of the interference signal is reduced. The first-stage synthesis determination means decodes a signal obtained by synthesizing the despread signals of the respective series of the first stage, and outputs first-stage reception data. Series of interference cancellers
A replica of the interference signal included in the direct spread received signal of each of the sequences is generated based on the output of the combining determination unit at the preceding stage, and the replica is subtracted from the direct spread received signal of each of the sequences to obtain the interference. Outputting a despread signal of each sequence of the stage in which the influence of the signal is reduced, wherein the combining determination means in the second and subsequent stages decodes a signal obtained by combining the despread signals of the respective sequences of the stage; The error detection means of each stage, along with the cascade operation of the interference cancellers of the plurality of stages, an error detection code based on the reception data output by the combination determination means of the stage. By performing the decoding of the above, an error is detected in units of the block of the block error detection coded data, In accordance with the detection result, in the block subsequent to the block subjected to the error detection by the error detection means in each of the stages, the number of operating stages of the plurality of stages of interference cancellers is controlled and the reception data of each stage is controlled. A direct-sequence receiving apparatus for selecting received information based on any one of them. 11. A direct-spread receiving apparatus for generating transmission data based on data obtained by performing transmission-block-error-detection-encoding on transmission information and receiving a direct-spread signal obtained by directly spreading the transmission data, comprising: An output unit, a plurality of stages of interference cancellers, an initial error detection unit, at least one stage error detection unit provided corresponding to a stage immediately before the last stage of the interference canceller,
And output selection means, wherein the initial data output means outputs initial reception data based on a direct spread reception signal, and the first stage interference canceller outputs the direct spread data based on the initial reception data. A replica of the interference signal included in the received signal is generated, the replica is subtracted from the direct spread reception signal, and the reception data in which the influence of the interference signal is reduced is output. Based on the output of the interference canceller at the previous stage, generate a replica of the interference signal included in the direct spread received signal, subtract the replica from the direct spread received signal, the effect of the interference signal is reduced The received data of the first stage is output, and the initial error detecting means decodes the error detection code based on the initial received data, thereby Error detection is performed in units of blocks of coded data, and the error detection means of each stage, with the cascade operation of the plurality of stages of interference cancellers, outputs the interference canceller of the stage. By performing decoding of an error detection code based on received data, an error is detected in units of the block of the block error detection encoded data, and the output selection unit includes the initial error detection unit and each of the stages. According to the error detection result of the error detection unit, in the block subsequent to the block that has been subjected to the error detection by the initial error detection unit and the error detection unit in each stage, the operation of the plurality of stages of interference cancellers is disabled. And controlling the number of operation stages and selecting reception information based on one of the initial reception data and the reception data of each stage. That, spread receiver device directly, characterized in that. 12. A direct spread receiving apparatus for generating transmission data based on data obtained by performing block error detection coding on transmission information, and receiving a direct spreading signal obtained by directly spreading the transmission data, comprising: An output unit, a plurality of stages of interference cancellers of a plurality of stages, a plurality of stages of combination determination units, an initial error detection unit, at least one stage error detection unit corresponding to a stage immediately before the last stage of the combination determination unit, and an output selection Means, the initial data output means receives the direct spread signal with an antenna corresponding to the plurality of streams, and outputs common initial receive data based on the direct spread receive signals of each stream, The interference cancellers of the respective series of one stage include, based on initial reception data common to the respective series, the direct cancel reception signals of the respective series. Generate a replica of the interference signal to be included, subtract the replica from the direct spread received signal of each of the series, output a despread signal of each series of the first stage reduced the influence of the interference signal, The first-stage synthesis determination means decodes a signal obtained by synthesizing the despread signal of each of the first-stage sequences, outputs first-stage received data, and outputs the first-stage reception data. The interference canceller
Based on the output of the combining determination means at the previous stage, generate a replica of the interference signal included in the direct sequence reception signal of each of the series, subtract the replica from the direct sequence reception signal of each of the series, the Outputting the despread signal of each sequence of the stage in which the influence of the interference signal is reduced; and the combining determination means of the second and subsequent stages decodes a signal obtained by combining the despread signals of the respective sequences of the stage. And outputs the reception data of the stage. The initial error detection means decodes the error detection code based on the initial reception data common to the respective streams, thereby obtaining the block error detection encoded data. The error detection means of each stage is associated with the cascade operation of the interference cancellers of the plurality of stages. Decoding the error detection code based on the received data to be input, thereby detecting an error in units of the block of the block error detection encoded data, and the output selection unit includes the initial error detection unit and the According to the error detection result of the error detection unit of each stage, in the block subsequent to the block that has been subjected to error detection by the initial error detection unit and the error detection unit of each stage, the plurality of stages of interference cancellers A direct spread receiving apparatus, comprising controlling inactivity and the number of operation stages, and selecting reception information based on any one of the initial reception data and the reception data of each stage.