CN101502006B - A multi-user interference cancellation RAKE receiver device and method - Google Patents

Abstract

A multi-user interference cancellation RAKE receiver device in a broadband CDMA system additionally includes an interference reconstruction unit (210) and an interference elimination unit (211) on the basis of traditional RAKE receivers. The interference reconstruction unit (210) carries out interference reconstruction for the user data which has a spread spectrum factor less than or equal to the first threshold and then obtains interference data equal to the sampling rate of initial antennae data. The interference elimination unit (211) compares the delay controlled initial antennae data (208) received by antennae data delay control unit (202) with the interference data, makes a subtraction, obtains interference canceled antennae data (207) and sends it to the antennae data delay control unit (202). The data is delay controlled and used to demodulate other non-highspeed uplink data service users.

Description

A RAKE receiver device for multi-user interference cancellation and its working method

technical field

The present invention relates to the uplink reception technology of the baseband processor of the base station of Wide Band Code Division Multiple Access (WCDMA, Wide Band Code-Division Multiple Access), in particular to the RAKE receiver hardware implementation device and its working method under the condition that the uplink reception of the base station supports high-speed data services .

Background technique

In a WCDMA wireless communication system, because the space wireless transmission environment is complex and harsh, a RAKE receiver device is usually used for reception. As shown in Figure 1, it shows the structure of the RAKE receiver device of the traditional base station baseband processor, including: antenna data delay control unit, RAKE demodulation unit, control channel symbol processing unit, data channel symbol maximum ratio combining unit.

When the RAKE receiver is working, the input antenna data is directly input to the antenna data delay control unit; the antenna data delay control unit sends the antenna data to the RAKE demodulation unit by controlling the antenna data delay.

The RAKE demodulation unit descrambles and despreads the delayed antenna data sent by the antenna data delay control unit. In the RAKE demodulation unit, the dedicated physical control channel (DPCCH, Dedicated Physical Control Channel) and dedicated physical The data channel (DPDCH, DedicatedPhysical Data Channel) performs multipath demodulation. Among them, the dedicated physical control channel obtains the user's control channel symbol data after multipath demodulation, and outputs it to the control channel symbol processing unit; the dedicated physical data channel obtains the user's data channel symbol data after multipath demodulation, and outputs it to the data channel Signed max ratio merging unit.

The control channel symbol processing unit performs channel estimation and TFCI (Transport Format Combination Indicator, Transport Format Combination Indicator) decoding processing on the control channel symbol data, generates channel estimation values for each multipath, and performs TFCI decoding to obtain each The user's actual spreading factor (SF, Spreading Factor), output the channel estimation and TFCI decoding results to the data channel symbol maximum ratio combining unit.

The data channel symbol maximum ratio merging unit, according to the channel estimation value and the actual spreading factor SF sent by the control channel symbol processing unit, performs channel compensation on the data channel symbols of each user sent by the RAKE demodulation unit after demodulation is completed Combine and accumulate with the maximum ratio to obtain the final data symbol of the data channel.

For WCDMA system, it is an interference limited system.

For general uplink voice services, since the spreading factor is relatively large (generally SF>=64), satisfactory performance can be obtained by using a traditional RAKE receiver, and the transmit power of the corresponding mobile station does not need to be very high. Therefore, the base station can Support more users.

But for the uplink data service, especially the HSUPA (High Speed Uplink Packet Access) proposed by the R6 protocol, the spreading factor is very small (SF<=4), and the mobile phone needs a higher transmission power to Ensure that the base station can receive the information of the mobile phone by using the traditional RAKE receiver. When the traditional RAKE receiver of the base station receives the HSUPA user service, because the mobile phone signal adopts higher transmission power, and other non-HSUPA user service signals (such as uplink voice service) are relatively small in power, other users demodulate the HSUPA user service The interference is relatively negligible.

But at this time, the HSUPA signal of the mobile phone occupies a relatively large part of the antenna signals received by the entire base station. When the traditional RAKE receiver demodulates the services of other non-HSUPA users, it will cause greater interference, causing other The user's signal is interfered and overwhelmed. In this way, other users must also increase the transmission power to allow the base station to receive the information of these users. The number of users decreased.

In short, for the base station equipment of the traditional RAKE receiver device, when a user of high-speed uplink data service appears, it will seriously affect the normal use of other users, resulting in a decrease in the number of users accessing, or even being unable to access. Therefore, there is a need for a device that can reduce the interference of high-speed data service users to other users, so as to avoid or alleviate the situation of power increase and user number decrease caused by interference.

Contents of the invention

The technical problem to be solved by the present invention is to provide a WCDMA system multi-user interference cancellation RAKE receiver device and its working method, which are used to offset the interference of high-speed uplink data service users on other non-high-speed uplink data service users, and ensure the existence of WCDMA The number of users in the case of high-speed uplink data services overcomes the shortcomings of traditional RAKE receivers that cause interference to other users during high-speed uplink data services, resulting in a sharp decrease in the number of users.

The present invention provides a multi-user interference canceling RAKE receiver device of a wideband code division multiple access system, including a RAKE demodulation unit, and the RAKE demodulation unit is respectively connected with an antenna data delay control unit, a control channel symbol processing unit, and a data channel symbol processing unit. The maximum ratio merging unit is connected. At the same time, the control channel symbol processing unit is also connected to the data channel symbol maximum ratio merging unit. The feature is that the device also includes an interference reconstruction unit and an interference elimination unit, wherein:

The interference reconstruction unit is respectively connected to the data channel symbol maximum ratio combining unit and the control channel symbol processing unit, and receives the data channel data symbols of the high-speed uplink data service user from the data channel symbol maximum ratio combining unit, and according to the expanded data symbols carried by the data symbols The frequency factor determines whether the user needs to perform interference reconstruction. When the spreading factor is less than or equal to the first threshold, according to the user scrambling code and channelization code information received from the control channel symbol processing unit, the user's data channel data symbol Perform interference reconstruction to obtain interference data with the same sampling rate as the antenna data and output to the interference cancellation unit, otherwise directly output the user's data channel data symbols for symbol-level processing;

The interference elimination unit receives the initial antenna data from the antenna from the antenna data delay control unit, aligns with the interference data output from the interference reconstruction unit, and subtracts them to obtain the antenna data with interference removed, and sends it to the antenna data delay control unit , for RAKE demodulation of other users.

Further, in the RAKE receiver device described in the present invention:

The antenna data delay control unit is used to perform delay control on the initial antenna data received from the antenna and the antenna data received from the interference cancellation unit after multi-user interference cancellation, and send the initial antenna to the RAKE solution The modulation unit is used for data demodulation of high-speed uplink data service users, and sends the antenna data after interference cancellation to the RAKE demodulation unit for data demodulation of other non-high-speed uplink data service users;

The RAKE demodulation unit performs multipath demodulation on the antenna data sent by the antenna data delay control unit to obtain data symbols of different users, and sends them to the control channel symbols according to the user's control channel data symbols and data channel data symbols respectively A processing unit and a data channel symbol maximum ratio combining unit;

The control channel symbol processing unit is configured to process the control channel data symbols of each user received from the RAKE demodulation unit, generate channel estimation values for each multipath, and perform transport format combination indicator decoding to obtain each The actual spreading factor of each user, the channel estimation value and the spreading factor are sent to the data channel symbol maximum ratio combining unit, and the scrambling code and channelization code information of each high-speed uplink data service user are sent to the interference reconstruction unit;

The maximum ratio merging unit of the data channel symbol, according to the channel estimation value and the actual spreading factor sent by the control channel symbol processing unit, performs the data channel data symbol of each user sent after the RAKE demodulation unit demodulates The channel compensation and the maximum ratio are combined and accumulated to obtain the final data channel data symbols, and the data channel data symbols of each high-speed uplink data service user are sent to the interference reconstruction unit.

Further, the interference reconstruction unit includes: a comparator, an accumulator, a pulse shaping filter, an interpolation filter, and a first multiplier between the comparator and the accumulator corresponding to each user , second multiplier, scrambling code and channelization code generation module, wherein:

The comparator is used to receive the data symbols of the data channel of each user of the high-speed uplink data service, and judge whether the user needs to perform interference reconstruction according to the actual spreading factor of each user, when the spreading factor is less than or equal to the first threshold , and send it to the first multiplier corresponding to the user, otherwise, directly output the data symbols of the user's data channel for symbol-level processing;

The first multiplier multiplies the data symbols of the data channel received from the comparator and the user's channel estimation parameters to obtain data symbols with channel information and send them to the second multiplier;

The scrambling code and channelization code generation module, according to the user's actual spreading factor, scrambling code and channelization code parameters received from the control channel symbol processing unit, generates the user's scrambling code and channelization code and sends them to the second multiplication device;

The second multiplier performs spreading and scrambling on the data symbols with channel information received from the first multiplier according to the user's scrambling code and channelization code received from the scrambling code and channelization code generating module multiplication operation, outputting the user's chip data with channel information to the accumulator;

The accumulator accumulates the chip data with channel information received from the second multiplier corresponding to each user of the high-speed uplink data service, and outputs the reconstructed chip data with channel information of all users to the pulse shaping filter;

The pulse shaping filter performs pulse shaping processing on the reconstructed chip data with channel information of all received high-speed uplink data service users, and sends it to the interpolation filter;

The interpolation filter performs interpolation processing on the reconstructed chip data with channel information of all users after pulse shaping processing to obtain interference data with the same sampling rate as the actual initial antenna data of the users, and outputs it to the interference elimination unit.

Further, the interference reconstruction unit receives the data symbols of the data channel of the high-speed uplink data service user from the data channel symbol maximum ratio combination unit, and judges whether the user needs to perform interference reconstruction according to the spreading factor therein, if If the spreading factor is greater than the first threshold, the data symbols of the user's data channel are directly output for symbol-level processing.

Further, the first threshold of the spreading factor is equal to 4.

Further, the interference elimination unit includes a delayer and a subtractor, wherein:

a delayer, configured to delay the initial antenna data input from the antenna end, and align the initial antenna data with the interference data received from the interference reconstruction unit;

The subtractor is used to perform subtraction operation on the delay-aligned initial antenna data and the interference data output by the interference reconstruction unit, output the antenna data after removing the interference of the high-speed uplink data service signal, and send it to the antenna data delay control The unit is used for data demodulation of other non-high-speed uplink data service users.

The present invention also provides a working method based on the multi-user interference canceling RAKE receiver device, comprising the following steps:

(1) For the initial antenna data from the antenna, after delay control by the antenna data delay control unit, it is sent to the RAKE demodulation unit, the control channel symbol processing unit, and the data channel symbol maximum ratio combining unit for processing. The unit obtains the channel estimation value of each multipath, the actual spreading factor, the scrambling code and channelization code information of each user, and obtains the data symbols of the data channel of the high-speed uplink data service user in the data channel symbol maximum ratio combination unit, and sends the Incoming interference reconstruction unit;

(2) Interference reconstruction is performed by the interference reconstruction unit on the data symbols of the high-speed uplink data service user data channel whose input spreading factor is less than or equal to the first threshold, and the interference data with the same sampling rate as the initial antenna data is obtained and sent to the interference Eliminate unit;

(3) The initial antenna data through the delay control is received by the interference elimination unit, and is subtracted after being aligned with the interference data output by the interference reconstruction unit, and the antenna data obtained by removing the interference is sent to the antenna data delay control unit. It is used for RAKE demodulation of other users after time control.

Further, step (1) further includes:

(1-1) The antenna data delay control unit sends the initial antenna data delay control received from the antenna to the RAKE demodulation unit;

(1-2) The initial antenna data sent by the antenna data delay control unit is multipath demodulated by the RAKE demodulation unit to obtain data symbols of different users, which are sent according to the user's control channel data symbols and data channel data symbols respectively For the control channel symbol processing unit and the data channel symbol maximum ratio combining unit;

(1-3) Process the control channel data symbols of each user received from the RAKE demodulation unit by the control channel symbol processing unit, generate the channel estimation value of each multipath, and decode the transport format combination indicator to obtain The actual spreading factor of each user, the channel estimation value and the spreading factor are sent to the data channel symbol maximum ratio combination unit, and the scrambling code and channelization code information of each high-speed uplink data service user is sent to the interference reconstruction unit;

(1-4) According to the channel estimation value and the actual spreading factor sent by the control channel symbol processing unit, the data channel of each user sent after the demodulation of the RAKE demodulation unit is completed by the maximum ratio combining unit of the data channel The data symbols are subjected to channel compensation and maximum ratio combining and accumulation, and the data symbols of the data channels of the high-speed uplink data service users are obtained and sent to the interference reconstruction unit.

Further, step (2) further includes:

Utilize the comparator to receive the data symbols of the data channel of each user, compare the actual spreading factor therein with the first threshold, when the spreading factor is greater than the first threshold, directly output the data symbols of the user's data channel, otherwise , using the first multiplier corresponding to the user to multiply the data symbols of the received data channel and the channel estimation parameters of the user to obtain data symbols with channel information, wherein the value of the first threshold is 4;

According to the user's actual spreading factor, scrambling code and channelization code parameters received from the control channel symbol processing unit, the scrambling code and channelization code generation module generates the user's scrambling code and channelization code;

According to the user's scrambling code and channelization code received from the scrambling code and channelization code generating module, the second multiplier performs spreading and scrambling on the data symbols with channel information received from the first multiplier Multiplication operation, output the user's chip data with channel information to the accumulator;

Using the accumulator to accumulate the chip data with channel information received from the second multiplier corresponding to each user, to obtain the reconstructed chip data with channel information of all users and output to the pulse shaping filter;

Using the pulse shaping filter to perform pulse shaping processing on the received reconstructed chip data with channel information of all users, and send it to the interpolation filter;

Interpolation processing is performed on the reconstructed chip data with channel information of all users after the pulse shaping processing by using an interpolation filter to obtain interference data with the same sampling rate as the actual antenna data of the users, and output to the interference elimination unit.

Further, in described step (3), further can be divided into:

using a delayer to delay the initial antenna data input from the antenna end, and align the input antenna data with the interference data received from the interference reconstruction unit;

Utilize the subtractor to perform subtraction operation on the antenna data after common input delay alignment and the antenna interference data output by the interference reconstruction unit, output the antenna data after removing the interference of the high-speed uplink data service signal, and send it to the antenna data delay control unit, After delay control, it is used for RAKE demodulation of other non-high-speed uplink data service users.

The multi-user interference cancellation RAKE receiver device of the present invention, on the basis of the traditional RAKE receiver device, increases the function of performing interference reconstruction and interference cancellation when the high-speed uplink data service is used as interference to other users, and after the interference is canceled The antenna data of the antenna are used for RAKE demodulation of other non-HSUPA users. Therefore, when the high-speed uplink data service exists in the traditional RAKE receiver, the disadvantage that other users cannot access or the access performance is not good is improved. Moreover, when the present invention is implemented, only a small number of interference reconstruction and interference elimination functions of high-speed uplink data service users are added, and the control and implementation are relatively simple, easy to implement, and use less hardware resources.

In short, compared with the traditional RAKE receiver, although some hardware resources have been added, the uplink reception performance of the base station has been improved, the interference between high-speed uplink data service users and other users has been minimized, and the interference caused by increased interference has been avoided. problems such as the decrease in the number of users or even the inability to access.

Figure overview

FIG. 1 is a schematic structural diagram of a traditional RAKE receiver device in a WCDMA system;

FIG. 2 is a schematic diagram of a multi-user interference cancellation RAKE receiver device in an embodiment of the present invention;

FIG. 3 is a structural diagram of an interference reconstruction unit in a multi-user interference cancellation RAKE receiver device in an embodiment of the present invention;

FIG. 4 is a structural diagram of an interference canceling unit in a multi-user interference canceling RAKE receiver device in an embodiment of the present invention.

Preferred Embodiments of the Invention

The technical solutions of the present invention will be described in further detail below in conjunction with the accompanying drawings and specific embodiments.

In order to overcome the shortcomings of the traditional RAKE receiver that interferes with other users (non-high-speed uplink data service users) when accessing high-speed uplink data services, resulting in a sharp decrease in the number of users, and ensure the number of users in the presence of WCDMA high-speed uplink data services, This embodiment provides a RAKE receiver device based on WCDMA multi-user interference cancellation.

For a RAKE receiver in a WCDMA system, there may be the following three situations when accessing a user:

(1) All non-HSUPA users access. At this time, since the interference is 0, it is equivalent to antenna data delay, and its access process corresponds to the traditional RAKE access process;

(2) There are both HSUPA users and non-HSUPA users;

Since HSUPA is an E-DCH channel, it is different from the physical channel of non-HSUPA users. The judgment of SF<=4 during RAKE processing is only for HSUPA users. For antenna data after cancellation, the so-called interference cancellation refers to performing interference reconstruction on HSUPA data as interference in the initially input antenna data, and subtracting the reconstructed interference data.

(3) All are HSUPA users;

RAKE processing can be performed with directly input antenna data.

As shown in FIG. 2 , a schematic structural diagram of a RAKE receiver device for multi-user interference cancellation in a WCDMA system provided by this embodiment is given. The device includes: an antenna data delay control unit, a RAKE demodulation unit, a control channel symbol processing unit, a data channel symbol maximum ratio combination unit, an interference reconstruction unit, and an interference elimination unit. Compared with the traditional RAKE receiver device shown in FIG. 1 , the RAKE receiver device for multi-user interference cancellation shown in FIG. 2 newly adds an interference reconstruction unit and an interference cancellation unit on the basis of the traditional RAKE receiver device.

The RAKE receiving device shown in Figure 2, when there is a high-speed uplink data service (HSUPA) user access, the antenna data initially received from the antenna end includes HUSPA user services and other non-HUSPA user services (such as voice service user services ), the antenna data is connected to the antenna data delay control unit. The RAKE receiving device caches the antenna data. When the base station chooses to access the high-speed uplink data service user, because of its high access power, its access will not be affected by the interference of other non-HSUPA service users, so It can directly perform descrambling and despreading, and output corresponding specific physical control channel symbols and specific physical data channel symbols. Conversely, when the base station selects other non-HSUPA service users to access, the high-speed uplink data service will cause serious interference to the access of other non-HSUPA service users, and affect the access of other users and the number of access users.

In order to overcome the interference caused by high-speed uplink data service users to other user access, in the RAKE device in this embodiment, the interference reconstruction unit performs interference reconstruction on the data channel symbols of high-speed uplink data service in the antenna data, and sends the interference The cancellation unit, finally, the interference-cancelled antenna data output by the interference cancellation unit is returned to the antenna data delay control unit as a new antenna data stream for RAKE demodulation of other users. in:

1) The interference reconfiguration unit first judges whether to participate in the interference reconfiguration according to the actual SF of the HSUPA user. If the SF<=4, the interference reconfiguration is performed on the data symbols of the user's data channel, otherwise the interference reconfiguration is not performed. Interference reconstruction is to multiply the data symbol of the HSUPA user data channel by the user's channel estimation parameter, and then perform scrambling and spreading according to the user's actual SF, user's scrambling code number and spreading code number. Finally, the scrambled and expanded data of multiple users is accumulated as the total interference, and then pulse shaping and interpolation are performed to obtain interference data with the same sampling rate as the antenna data and sent to the interference elimination unit.

2) The interference elimination unit is to delay the initial input antenna data (including HSUUPA user and non-HSUPA user data), and then subtract it from the interference data output by the interference reconstruction unit, and the result is to remove the interference antenna data (i.e. non-HSUPA user data), and then, the output result is sent back to the antenna data delay control unit as an antenna data stream, and then sent to the RAKE demodulation unit as the RAKE demodulation of other users (non-high-speed uplink data service users) Antenna data used.

In the multi-user interference cancellation RAKE receiver device shown in Figure 2, the functions of the existing modules are as follows:

The antenna data delay control unit is used to cache and delay the initial input antenna data, and control the antenna data after multi-user interference cancellation, and jointly perform antenna data stream numbering for subsequent RAKE demodulation The unit sends the antenna data after multi-user interference cancellation to the subsequent RAKE demodulation unit to descramble and despread the antenna data of other non-high-speed uplink data service users;

The RAKE demodulation unit performs multipath demodulation on the antenna data sent by the antenna data delay control unit to obtain the symbol data of different users, and sends them to the control channel symbol processing unit and data channel symbols respectively according to the user's control channel and data channel Maximum ratio merging unit;

The control channel symbol processing unit is to process the control channel symbols of each user sent by the RAKE demodulation unit after demodulation, generate the channel estimation value of each multipath, and perform TFCI decoding to obtain the actual SF, sending these information to the data channel symbol maximum ratio combination unit for maximum ratio combination, and at the same time, sending the scrambling code and channelization code information of the HSUPA user to the interference reconstruction unit;

The data channel symbol maximum ratio merging unit, according to the channel estimation value and the actual SF sent by the control channel symbol processing unit, performs channel compensation and maximum ratio on the data channel symbols of each user sent by the RAKE demodulation unit after demodulation is completed. Combine and accumulate to obtain the final data symbols of the data channel. Send the data symbols of the final data channel of the HSUPA user to the interference reconstruction unit.

Fig. 3 is a structural diagram of an interference reconstruction unit in the multi-user interference cancellation RAKE receiver device provided by this embodiment. As shown in FIG. 3 , the interference reconstruction unit mainly includes: a comparator, a multiplier, n sets of scrambling code and channelization code generation modules, an accumulator, a pulse shaping filter and an interpolation filter.

In Fig. 3, the data symbols of each high-speed uplink data service user's final data channel from the data channel symbol maximum ratio combining unit pass through a comparator that judges according to the user's SF, wherein when SF<=4, the The data symbols of the user's final data channel enter the next stage of processing through the comparator, otherwise, because SF>4, the interference to other users is small, and can be directly output for symbol-level processing.

The data symbols passing through the comparator are firstly multiplied with the channel estimation parameters of the high-speed uplink data service user to obtain the data symbols with channel information; then these data symbols are multiplied by adding, spreading and scrambling to obtain the channel information of the user chip data. Among them, the channelization code and scrambling code required for adding, spreading and scrambling come from the scrambling code and channelization code generation module, which generates the channelization code and scrambling code according to the user parameters such as the user's scrambling code number and channelization code number of.

The multi-user in the interference reconstruction unit refers to the situation that the initially received antenna data contains multiple HSUPA users, and the data of each HSUPA user is subjected to interference reconstruction to obtain the total interference data of all HSUPA users.

The data symbol of the data channel of user 1 is first multiplied by the channel parameters of user 1, and the scrambling code and channelization code generation module 1 generates the scrambling code and channelization code according to the parameters of user 1, and the second multiplier corresponding to user 1 Perform the multiplication operation of adding, spreading and scrambling to obtain the chip data with channel information of user 1;

The data symbol of the data channel of user 2 is first multiplied by the channel parameters of user 2, and the scrambling code and channelization code generation module 2 generates the scrambling code and channelization code according to the parameters of user 2, and the second multiplier corresponding to user 2 The multiplication operation of adding, spreading and scrambling is performed to obtain the chip data of user 2 with channel information.

...

The data symbol of the data channel of user n is first multiplied by the channel parameters of user n, and the scrambling code and channelization code generation module n generates the scrambling code and channelization code according to the parameters of user n, and the second multiplier corresponding to user n The multiplication operation of adding, spreading and scrambling is performed to obtain the chip data with channel information of user n.

The reconstructed antenna data of all HSUPA users are accumulated in the accumulator to obtain the reconstructed chip data with channel information of all users, but at this time these chip data are 1 times the chip rate, which is different from the actual antenna data sampling The rates are different, and the actual antenna data is also passed through a pulse-shaping filter. In order to obtain real reconstructed antenna data, the chip data accumulated by HSUPA multi-users needs to pass through the pulse shaping filter and then the interpolation filter, so that the same sampling rate as the actual antenna data can be obtained. In this way, the reconstruction of the interference data is completed, and the reconstructed interference data is output to the subsequent interference elimination unit for interference elimination.

Fig. 4 is a structural diagram of an interference canceling unit in the multi-user interference canceling RAKE receiver device provided by this embodiment. The interference elimination unit is mainly composed of a delayer and a subtractor, wherein:

The delayer is used to delay the antenna data initially input by the antenna end so that it is aligned with the antenna interference signal output by the interference reconstruction unit;

The delayed initial antenna data and the antenna interference signal output by the interference reconstruction unit are jointly input to the subtractor for subtraction, and the output is the antenna data after removing the interference of the high-speed uplink data service signal, that is, in the antenna data that eliminates the interference, It no longer contains high-speed uplink data service signals, but only contains non-high-speed uplink data service signals. The antenna data that eliminates interference is returned to the antenna data delay control unit and sent to the RAKE demodulation unit for RAKE of other non-HSUPA service users. demodulation, so as to achieve the purpose of reducing interference.

Based on the RAKE receiver device for multi-user interference cancellation shown in FIG. 2 above, the flow of multi-user interference cancellation includes the following steps:

Step 1: The antenna data initially input from the antenna is sent to the antenna data delay control unit, and the antenna data delay control unit performs delay processing on the initial input antenna data, and judges HSUPA and non-HSUPA. For HSUPA, the initial The received antenna data is sent to the RAKE demodulation unit for demodulation, and for non-HSUPA, the antenna data after interference cancellation is sent to the RAKE demodulation unit for demodulation.

Step 2: The RAKE demodulation unit descrambles and despreads the various input antenna data streams, and sends the demodulated user control channel symbol data and data channel symbol data to the control channel symbol processing unit and data channel respectively. Channel symbol maximum ratio combining unit;

Step 3: The control channel symbol is processed by the control channel symbol processing unit to generate the channel estimation value of each multipath, and perform TFCI decoding to obtain the actual SF of each user, and send the channel estimation and actual SF information to Give the data channel symbol maximum ratio merging unit, and at the same time send the channel estimation, actual SF, scrambling code number, and spreading code number of each HSUPA user to the interference reconstruction unit as channel parameters;

Step 4: The data channel symbol maximum ratio merging unit, according to the channel estimation value and the actual SF sent by the control channel symbol processing unit, performs the data channel symbol of each HSUPA user sent after the demodulation of the RAKE demodulation unit is completed. The channel compensation and the maximum ratio are combined and accumulated to obtain the final data channel data symbols and send them to the interference reconstruction unit;

Step 5: The interference reconstruction unit first judges whether to perform interference reconstruction on the received data symbols, selects the data symbols of the data channel of the user whose SF<=4 is multiplied by the user's channel estimation value parameter, and then according to the user's The actual SF, the user's scrambling code number and spreading code number are scrambled and expanded, and multi-users are accumulated, and then the data stream with the same sampling rate as the antenna data is obtained through the pulse shaping filter and the interpolation filter and sent to the interference Elimination unit; if SF>4, the data symbols of the HSUPA user can be directly output for symbol-level processing.

Step 6: The interference elimination unit first delays the input antenna data and aligns it with the interference signal output by the interference reconstruction unit, then subtracts the input interference data from the input antenna data to obtain the interference-eliminated antenna data, and then sends it to The antenna data delay control unit is used for RAKE demodulation of other users.

For high-speed uplink data services, when the spreading factor SF=2 or 4, especially when SF=2, the inter-code interference between other user channels is very large due to the channelization code tree, and the inter-code interference is very large. However, using The device and method of the present invention perform interference reconstruction and interference elimination on the data of the user SF<=4 of the high-speed uplink data service, and use it for RAKE demodulation of other users after re-input, which can effectively reduce the interference with other non-high-speed uplink data. Intersymbol interference between data service users.

To sum up, by adding interference cancellation and interference reconstruction, the high-speed uplink data service is canceled as the interference of other users, so that the antenna data after interference cancellation is used for RAKE demodulation of other users, thereby improving the traditional RAKE When the receiver has high-speed uplink data services, other users cannot access or have poor access performance. The invention improves the uplink receiving performance of the base station, and ensures that the system can still support more users in the case of high-speed uplink data services.

Industrial Applicability

The multi-user interference cancellation RAKE receiver device disclosed by the present invention can effectively cancel the impact on other users when accessing a user of high-speed uplink data service in a WCDMA system, and avoid or reduce power increase and user number decrease caused by interference.

Claims (10)

1. the multi-user interference cancellation RAKE receiver device of a broadband CDMA system; Comprise the RAKE demodulating unit, this RAKE demodulating unit links to each other with antenna data time-delay control unit, control channel symbol processing unit, data channel symbol high specific merge cells respectively, simultaneously; Control channel symbol processing unit also links to each other with data channel symbol high specific merge cells; It is characterized in that this device also comprises interference reconstruction unit and interference cancellation unit, wherein:

Interference reconstruction unit; Link to each other with data channel symbol high specific merge cells, control channel symbol processing unit respectively; Receive high speed uplink data service user's data channel data symbol from data channel symbol high specific merge cells; The spreading factor that carries according to said data symbol is judged this user, and whether needs disturb reconstruct; When spreading factor is less than or equal to first threshold,, this user's data channel data symbol is disturbed reconstruct according to the user's scrambler and the channelization code information that receive from control channel symbol processing unit; Obtain the interfering data the same and export interference cancellation unit to, carry out the symbol level processing otherwise directly export this user's data channel data symbol with the antenna data sample rate;

Interference cancellation unit; Receive initial antenna data from antenna data time-delay control unit, and subtract each other after interfering data from interference reconstruction unit output aligns, obtain to remove the antenna data of interference from antenna; Deliver to antenna data time-delay control unit, be used for other user's RAKE demodulation.

2. multi-user interference cancellation RAKE receiver device as claimed in claim 1 is characterized in that:

Said antenna data time-delay control unit; Be used for the control of delaying time together of the initial antenna data that receive from antenna and the antenna data after process the multi-user interference elimination that said interference cancellation unit receives; The initial antenna data are sent to the RAKE demodulating unit be used for the demodulation of high speed uplink data service user's data, the antenna data after the interference eliminated is sent to the RAKE demodulating unit be used for other non-high speed uplink data service user's data demodulation;

Said RAKE demodulating unit; The antenna data antenna data that control unit sends here of delaying time is carried out multi-path demodulation; Obtain the data symbol of different user, give control channel symbol processing unit and data channel symbol high specific merge cells according to user's control channel data symbol and data channel signal symbol respectively.

Said control channel symbol processing unit; Be used for each user's of receiving from the RAKE demodulating unit control channel data symbol is handled; Produce the channel estimation value of every multipath and carry out transport format combination indicator decoding and obtain the actual spreading factor of each user; Channel estimation value and spreading factor are delivered to data channel symbol high specific merge cells, give interference reconstruction unit each high speed uplink data service user's scrambler and channelization code information;

Said data channel symbol high specific merge cells; Channel estimation value of sending here according to control channel symbol processing unit and actual spreading factor; Each user's data channel data symbol of sending here after the demodulation of RAKE demodulating unit accomplished carries out channel compensation, and merging adds up with high specific; Obtain the data symbol of final data channel, each high speed uplink data service user's data channel data symbol is delivered to interference reconstruction unit.

3. multi-user interference cancellation RAKE receiver device as claimed in claim 1 is characterized in that said interference reconstruction unit; Comprise: comparator; Accumulator, pulse shaping filter, interpolation filter; And between comparator and accumulator with each user first multiplier, second multiplier, scrambler and channel code generation module one to one, wherein:

Comparator; Be used to receive the data symbol of each user's data channel of high speed uplink data service; Whether needs disturb reconstruct to judge this user according to each user's actual spreading factor, when spreading factor is less than or equal to first threshold, send into the first corresponding multiplier of this user; Otherwise the data symbol of directly exporting this user's data channel carries out symbol level to be handled;

First multiplier carries out multiplying to the data symbol of the data channel that receives from comparator and this user's channel estimating parameter, and the data symbol that obtains having channel information is sent into second multiplier;

Scrambler and channel code generation module, according to spreading factor, scrambler and the channel code parameter of this user's who receives from control channel symbol processing unit reality, the scrambler and the channel code that produce this user are sent into second multiplier;

Second multiplier; Scrambler and channel code according to this user who receives from scrambler and channel code generation module; To the said data symbol that has channel information that receives from first multiplier; Add the multiplying of expanding scrambling, export chip data to the said accumulator of this user's the information of taking a message;

Accumulator adds up to the chip data of the information of taking a message that receives from the second corresponding multiplier of each user of high speed uplink data service, and the chip data of the information of taking a message that obtain all users' reconstruct export said pulse shaping filter to;

Pulse shaping filter to the chip data of the information of taking a message of all high speed uplink data service users' of receiving reconstruct, carries out pulse shaping and handles, and delivers to interpolation filter;

Insert in the chip data of the information of taking a message of all users' after interpolation filter, paired pulses be shaped to be handled reconstruct are carried out and handle, obtain the interfering data with the actual identical sampling rate of initial antenna data of user, export interference cancellation unit to.

4. multi-user interference cancellation RAKE receiver device as claimed in claim 1; It is characterized in that; Said interference reconstruction unit receives the data symbol of high speed uplink data service user's data channel from data channel symbol high specific merge cells, when judging this user according to spreading factor wherein needs disturb reconstruct; If, then directly exporting the data symbol of user's data channel greater than first threshold, spreading factor is used for the symbol level processing.

5. like claim 1 or 3 or 4 described multi-user interference cancellation RAKE receiver devices, it is characterized in that the first threshold of said spreading factor equals 4.

6. multi-user interference cancellation RAKE receiver device as claimed in claim 1 is characterized in that said interference cancellation unit comprises delayer and subtracter, wherein:

Delayer is used for to delaying time from the initial antenna data of antenna end input these initial antenna data being alignd with the interfering data that receives from interference reconstruction unit;

Subtracter; Be used for the interfering data that the initial antenna data and the interference reconstruction unit through the time-delay alignment of common input are exported is carried out subtraction; Output is delivered to antenna data time-delay control unit and is used for other non-high speed uplink data service user's data demodulation through removing the antenna data that high speed uplink data service signal disturbs.

7. the method for work based on the said multi-user interference cancellation RAKE receiver of claim 1 device is characterized in that, comprises the steps:

(1) to initial antenna data from antenna; After antenna data time-delay control unit time-delay control; Send into the RAKE demodulating unit and carry out multi-path demodulation; Obtain the data symbol of different user, give control channel symbol processing unit, data channel symbol high specific merge cells according to user's control channel data symbol and data channel signal symbol respectively, obtain the channel estimation value of every multipath, actual spreading factor, each user's scrambler and channelization code information at control channel symbol processing unit; Obtain the data symbol of high speed uplink data service user's data channel at data channel symbol high specific merge cells, send into interference reconstruction unit;

(2) by interference reconstruction unit the data symbol that the spreading factor of importing is less than or equal to the high speed uplink data service user data channel of first threshold is disturbed reconstruct, obtain the interfering data the same and deliver to interference cancellation unit with the initial antenna data sampling rate;

(3) receive initial antenna data by interference cancellation unit through time-delay control; With subtract each other after interfering data from interference reconstruction unit output aligns; Acquisition is removed the antenna data of interference and is delivered to antenna data time-delay control unit, and the RAKE demodulation that after time-delay control, is used for other user is used.

8. method of work as claimed in claim 7 is characterized in that, step further comprises in (1):

(1-1), send to the RAKE demodulating unit by of the initial antenna data time-delay control of antenna data time-delay control unit to receiving from antenna;

The initial antenna data of (1-2) by the RAKE demodulating unit antenna data time-delay control unit being sent here are carried out multi-path demodulation; Obtain the data symbol of different user, give control channel symbol processing unit and data channel symbol high specific merge cells according to user's control channel data symbol and data channel signal symbol respectively;

(1-3) each user's of receiving from the RAKE demodulating unit control channel data symbol is handled by control channel symbol processing unit; Produce the channel estimation value of every multipath and carry out transport format combination indicator decoding and obtain the actual spreading factor of each user; Channel estimation value and spreading factor are delivered to data channel symbol high specific merge cells, give interference reconstruction unit each high speed uplink data service user's scrambler and channelization code information;

The channel estimation value and actual spreading factor (1-4) sent here according to control channel symbol processing unit by data channel symbol high specific merge cells; Each user's data channel data symbol of sending here after the demodulation of RAKE demodulating unit accomplished carries out channel compensation, and merging adds up with high specific, and the data symbol that obtains high speed uplink data service user's data channel is delivered to interference reconstruction unit.

9. method of work as claimed in claim 7 is characterized in that, step further comprises in (2):

Utilize comparator to receive the data symbol of each user's data channel, wherein actual spreading factor and first threshold compared, when spreading factor during greater than first threshold; Directly export the data symbol of this user's data channel; Otherwise, utilize the first corresponding multiplier of this user, the data symbol of the data channel that receives and this user's channel estimating parameter are carried out multiplying; Obtain having the data symbol of channel information, the value of wherein said first threshold is 4;

According to spreading factor, scrambler and the channel code parameter of this user's who receives from control channel symbol processing unit reality, through scrambler and the channel code of scrambler with this user of channel code generation module generation;

Scrambler and channel code according to this user who receives from scrambler and channel code generation module; By the said data symbol that have channel information of second multiplier to receiving from first multiplier; Add the multiplying of expanding scrambling, the chip data of the information of taking a message of exporting this user are to accumulator;

Utilize accumulator that the chip data of the information of taking a message that receives from the second corresponding multiplier of each user are added up, the chip data of the information of taking a message that obtain all users' reconstruct export pulse shaping filter to;

Utilize the chip data of pulse shaping filter, carry out pulse shaping and handle, deliver to interpolation filter the information of taking a message of all users' of reception reconstruct;

Insert in the chip data of the information of taking a message of all users' after utilizing the interpolation filter paired pulses be shaped to handle reconstruct are carried out and handle, obtain the interfering data with the actual identical sampling rate of antenna data of user, export interference cancellation unit to.

10. method of work as claimed in claim 7 is characterized in that, said step further can be divided in (3):

Utilize delayer to delaying time, the initial antenna data of this input are alignd with the interfering data that receives from interference reconstruction unit from the initial antenna data of antenna end input;

The antenna data after utilizing subtracter to the time-delay alignment of common input and the antenna interference data of interference reconstruction unit output are carried out subtraction; Output is through removing the antenna data that high speed uplink data service signal disturbs; Deliver to antenna data time-delay control unit, after time-delay control, be used for other non-high speed uplink data service user's RAKE demodulation.

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