CN101043500B - Method for Determining Reverse Data Modulation and Coding Mode and Its Access Terminal - Google Patents

Abstract

The disclosed determining method for inverse data modulating way comprises: in a wireless access network, the access terminal determines self quality of inverse data channel according to the quality of inverse power-control reference channel, and determines the modulating and coding way for inverse data transmission. This invention can avoid scheduling error during the AN schedules AT, and reduces the effect on throughout of inverse data transmission.

Description

Method for Determining Reverse Data Modulation and Coding Mode and Its Access Terminal

technical field

The present invention relates to a terminal scheduling technology in an Orthogonal Frequency Division Multiplexing (OFDM, Orthogonal Frequency Division Multiplexing) system, in particular to a method for determining a reverse data modulation and encoding method and an access terminal thereof.

Background technique

Future mobile communication systems mainly adopt Orthogonal Frequency Division Multiplexing (OFDM, Orthogonal Frequency Division Multiplexing) multiple access methods, such as the Long Term Evolution (LTE, Long Term Evolution) system and Air Interface Evolution (AIE, Air Interface Evolution) proposed by 3GPP. ) systems and the like are evolving toward a direction based on OFDM multiple access methods (such as OFDMA). In the OFDM system, the transmitter maps the data symbols to different mutually orthogonal narrowband subcarriers after being processed by Inverse Discrete Fourier Transformation (IDFT, Inverse Discrete FourierTransformation), and then attaches a cyclic prefix to each narrowband subcarrier respectively. (CP, Cyclic Prefix) to form OFDM symbols for transmission; although after air propagation, the signal received by the receiving end will contain multiple multipath components with different delays, but the receiving end can use discrete Fourier transform (DFT, Discrete Fourier Transformation) processing to extract each data symbol sent by the transmitter on each orthogonal narrowband subcarrier, and each multipath component will automatically complete the equal gain combination after DFT processing, so that the OFDM system has an instinctive anti-multipath ability. It is precisely because OFDM technology has obvious advantages such as excellent anti-multipath ability, easy combination with multi-antenna technology and relatively simple receiver structure, it has become the main multiple access method adopted by future mobile communication systems.

In the OFDMA system, the wireless access network (AN, Access Network) will schedule wireless access terminals (AT, Access Terminal) each time, according to the current reverse channel quality and quality of service (QoS, Quality of Service) priority, the size of the data to be sent, the current power and other information to decide whether to schedule the corresponding AT and determine the packet length and transmission rate allocated to the corresponding scheduled AT, and send each scheduled AT The assigned AT sends an assignment message to notify the corresponding scheduled AT to send data according to the instructions of the AN. Each AT will report its own current power information, data size information to be sent, and QoS priority information to the AN according to the corresponding time rule. Since the AN has a reverse power control function for the AT, the reverse power control process is Because the AN needs to continuously measure the reverse channel quality of the AT, if the measurement result is greater than a predetermined threshold, the AN sends an instruction to notify the AT to reduce the transmission power, so as to save the power of the AT and reduce the interference to other ATs; at the same time If the measurement result is less than the predetermined threshold, the AN sends an instruction to inform the AT to increase the transmission power, so as to ensure that the reverse channel quality of the AT meets the transmission requirements of the system. At the same time, AN determines the reverse channel quality of each AT by measuring the reverse channel of the AT. Generally, for ATs with poor reverse channel quality, AN will instruct AT to send data at a lower transmission rate. A good AT, AN will instruct the AT to send data at a higher transfer rate.

To sum up, it can be seen that in the process of AN scheduling AT, AT needs to report more overhead information. For example, AN needs to know the current power information of AT, because the higher the rate level assigned by AN to AT, the more power AT needs to have. , and if the AN does not know the current power information of the AT, it may cause the AT to allocate a higher transmission rate, and if the current power of the AT itself cannot support the transmission rate allocated by the AN, it will affect the data of the AT. Transmission; AN also needs to know the size of the data that the scheduled AT currently needs to send, because AT currently needs to send a small amount of data, and AN allocates a higher transmission rate for it, which will cause waste of transmission resources, and AT currently needs to send a lot of data, and AN allocates a lower transmission rate for it, which will affect the data transmission throughput of AT; in addition, AN also needs to know the QoS priority information of AT's current data transmission service, so as to Very well meet the QoS requirements of different data services. Therefore, in general, AT needs to report the above overhead information to AN, so that AN can combine the reverse Channel quality to decide whether to schedule the AT and determine the packet length and transmission rate allocated to the AT when scheduling the AT. The AT reports the above overhead information to the AT through an overhead channel or in-band signaling. For the AN, since there is a delay in the processing and transmission of these overhead information by the AT, when the AN receives the overhead information reported by the AT, it determines whether to schedule the AT based on the overhead information and assigns the transmission rate to the AT when it is scheduled. When , the current power information of the AT and the size of the data to be sent may have changed, so it will cause scheduling errors for the AN to schedule the AT. However, in order to reduce this scheduling error as small as possible, it is necessary to AT continuously reports these overhead information, but this will inevitably affect the data transmission throughput of the AT reverse channel.

Contents of the invention

The present invention proposes a method for determining the reverse data modulation and coding mode, so as to solve the scheduling error caused by AN scheduling AT in the prior art, and avoid affecting the throughput of reverse channel data transmission.

Correspondingly, the present invention also provides an access terminal.

In order to solve the above problems, the technical scheme proposed by the present invention is as follows:

A method for determining a reverse data modulation and encoding method, comprising steps:

In the wireless access network, the access terminal determines the channel quality of its own reverse data channel according to the channel quality of the reverse power control reference channel indicated by the access network; and

According to the determined channel quality of the reverse data channel, the modulation and coding mode adopted for the reverse data transmission is determined.

Preferably, the process of the access network indicating the channel quality of the reverse power control reference channel to the access terminal specifically includes:

The adjustment step value is pre-agreed between the access network and the access terminal;

The access network periodically indicates the measured channel quality of the reverse power control reference channel to the access terminal; and

Instructing the access terminal to increase or decrease the agreed step value according to the change of the channel quality of the reverse data channel of the access terminal during the period when the channel quality is not indicated;

The access terminal increases or decreases the agreed step value on the channel quality of the last received reverse power control reference channel according to the instruction of the access network.

Preferably, the access network instructs the access terminal to increase or decrease the agreed step size according to the channel quality change of the reverse data channel, which specifically refers to:

When the access network measures an increase in the frame error rate of the reverse data channel of the access terminal, instruct the access terminal to decrease the agreed step value; and

Instructing the access terminal to increase the agreed step value when the frame error rate of the reverse data channel of the access terminal is measured to decrease.

Preferably, the access terminal multiplies the channel quality of the reverse power control reference channel indicated by the access network by a predetermined offset value as the channel quality of its own reverse data channel.

Preferably, the predetermined offset value is determined by the gain of the unit transmission unit transmission power of the reverse data channel of the access terminal relative to the unit transmission unit transmission power of the reverse power control reference channel.

Preferably, the method also includes the steps of:

The access terminal determines its own reverse data transmission rate based on the determined modulation and coding scheme adopted for reverse data transmission and in combination with frequency resources indicated to itself by the access network.

Preferably, the method also includes the steps of:

the access terminal transmits data on the reverse data channel based on the determined reverse data transmission rate; and

Report the determined modulation and coding method used for reverse data transmission to the access network;

The access network demodulates and decodes the reverse data transmitted by the access terminal according to the modulation and coding mode reported by the access terminal.

Preferably, the method also includes the steps of:

The access terminal reports the determined modulation and coding method adopted for reverse data transmission to the access network;

The access network determines frequency resources allocated to each access terminal according to the modulation and coding scheme reported by each access terminal; and

Indicating the frequency resource allocated to each access terminal to the corresponding access terminal respectively;

The access terminal determines its own reverse data transmission rate based on the determined modulation and coding scheme adopted for reverse data transmission and in combination with frequency resources indicated to itself by the access network.

Preferably, the method also includes the steps of:

the access terminal transmits data on the reverse data channel based on the determined reverse data transmission rate;

The access network demodulates and decodes the reverse data transmitted by the access terminal according to the modulation and coding mode reported by the access terminal.

Preferably, the method also includes the steps of:

The access terminal reports the determined modulation and coding method adopted for reverse data transmission to the access network;

The access network determines frequency resources allocated to each access terminal according to the modulation and coding scheme reported by each access terminal; and

Re-assign a new modulation and coding method for each access terminal;

The access network will indicate the frequency resources allocated to each access terminal and the new modulation and coding scheme assigned to each access terminal to the corresponding access terminal;

The access terminal determines its reverse data transmission rate based on the new modulation and coding scheme indicated by the access network and in combination with the frequency resources indicated by the access network.

Preferably, the method also includes the steps of:

the access terminal transmits data on the reverse data channel based on the determined reverse data transmission rate;

The access network demodulates and decodes the reverse data transmitted by the access terminal according to the corresponding modulation and coding mode assigned to the access terminal.

Preferably, the channel quality of the channel can be identified based on the signal-to-noise ratio of the channel.

An access terminal comprising:

The channel quality determining unit is used to determine the channel quality of the reverse data channel according to the channel quality of the reverse power control reference channel indicated by the access network in the wireless access network;

The modulation and coding mode determining unit is used to determine the modulation and coding mode adopted for the reverse data transmission according to the channel quality of the reverse data channel determined by the channel quality determining unit.

Preferably, the channel quality determination unit specifically includes:

The storage subunit is used to store an offset value in advance;

The channel quality caching subunit is used to cache the channel quality of the reverse power control reference channel indicated by the access network last time;

The multiplication subunit is used to multiply the channel quality of the reverse power control reference channel buffered by the channel quality buffer subunit by the offset value stored in the storage subunit, and use the multiplication result as the channel quality of the reverse data channel.

Preferably, the channel quality determining unit specifically further includes:

The step value storage subunit is used to store the pre-agreed adjustment step value between the access network and the access terminal;

An indication information receiving subunit, configured to receive indication information indicated by the access network to increase or decrease the agreed step value;

The step size adjustment subunit is configured to increase or decrease the agreed step size value according to the indication information received by the indication information receiving subunit to increase or decrease the channel quality of the reverse power control reference channel buffered by the channel quality buffering subunit.

Preferably, the access terminal further includes:

The first transmission rate determination unit is configured to determine the transmission rate of the reverse data based on the modulation and coding method adopted for the reverse data transmission determined by the modulation and coding method determination unit, in combination with the frequency resources indicated by the access network;

The first data transmission unit is configured to transmit data on the reverse data channel according to the reverse data transmission rate determined by the first transmission rate determination unit;

The first modulation and coding method reporting unit is configured to report the modulation and coding method used for reverse data transmission determined by the modulation and coding method determination unit to the access network.

Preferably, the access terminal further includes:

The second modulation and coding method reporting unit is used to report the modulation and coding method used for the reverse data transmission determined by the modulation and coding method determination unit to the access network;

The second transmission rate determination unit is configured to determine the transmission rate of reverse data based on the new modulation and coding scheme and frequency resources indicated by the access network;

The second data transmission unit is configured to transmit data on the reverse data channel according to the reverse data transmission rate determined by the second transmission rate determination unit.

The beneficial effect that the present invention can reach is as follows:

In the technical solution of the present invention, during the process of AN dispatching AT, the AT autonomously calculates the spectrum efficiency used by the reverse data according to the channel quality of the current reverse power control reference channel indicated by the AN, thereby correspondingly determining the frequency spectrum efficiency that the reverse data should use. modulation coding scheme (MCS). In this way, the AT can determine the transmission rate it needs to use to transmit reverse data without reporting overhead information such as its current power, data size to be sent, and QoS priority to the AN, thereby avoiding the transmission rate due to uplink overhead information. The scheduling error caused by the transmission delay enables the AN to schedule the AT more accurately; at the same time, it also reduces the AT's excessive occupation of reverse transmission resources in order to report relevant overhead information, and correspondingly improves the transmission of the reverse transmission channel. throughput.

Description of drawings

Fig. 1 is the flow chart of the main realization principle of the method for determining the reverse data modulation and coding mode of the present invention;

Fig. 2 is a schematic diagram of the processing procedure of the first embodiment in which the AT implements the transmission of uplink data according to the determined MCS information;

FIG. 3 is a schematic diagram of the processing process of the second embodiment in which the AT implements the transmission of uplink data according to the determined MCS information;

FIG. 4 is a schematic diagram of the processing process of the third embodiment in which the AT implements the transmission of uplink data according to the determined MCS information;

Fig. 5 is a specific structural block diagram of the access terminal proposed by the present invention;

FIG. 6 is a block diagram of the specific composition and structure of the channel quality determination unit in the access terminal of the present invention;

FIG. 7 is a structural block diagram of a first embodiment of an access terminal implementing uplink data transmission according to the present invention;

FIG. 8 is a structural block diagram of a second embodiment of an access terminal implementing uplink data transmission according to the present invention.

Detailed ways

In the actual mobile communication system, when the AN performs reverse power control on the AT, it always uses a reference channel as the reference. For example, in the DO Rev.A mobile communication system, the reverse power control reference channel is the reverse pilot channel. In the 802.02 mobile communication system, the reverse power control reference channel is a reverse channel quality indicator (CQI, Channel Quality Indicator) channel. During the reverse power control process of the AT by the AN, the AN continuously measures the channel quality of the reverse power control reference channel, and calculates the signal-to-noise ratio (SNR, Signal to Noise Ratio), if the calculated SNR is greater than the preset target SNR, then AN sends a power control command to AT, instructing AT to reduce the transmission power of the reference channel; otherwise, AN sends a power control command to AT, instructing AT to increase the reference channel The transmit power of the channel.

The power of the actual reverse data channel of the AT is obtained by multiplying the power of the reverse power control reference channel by an offset value (Delta). For example, assuming that the power of the reverse power control reference channel is 1 milliwatt, While the offset value of the reverse data channel is 10, the power of the reverse data channel should be 10 times the power of the reference channel, that is, the power of the reverse data channel is 10 milliwatts. The purpose of reverse power control is to maintain the channel quality of the reverse power control reference channel within a certain range. Even if the SNR of the reverse power control reference channel is maintained within a certain range, all ATs can consider their own reverse data channel transmission The quality is also stable based on the SNR of the reference channel multiplied by an offset value. Therefore, when the AT is scheduled by the AN, the AT can directly calculate its own reverse Data transmission rate, instead of reporting its own current power information, data size information to be sent, and QoS priority information to the AN every time it is scheduled (instead, a longer cycle length can be used to report these overhead information , only used by AN to allocate frequency resources), thereby avoiding the scheduling error that AN exists when scheduling AT each time, and reducing the occupation of AT reverse data channel transmission resources, and correspondingly increasing the transmission throughput of reverse data channel quantity.

The transmission subcarrier resources actually used by the ATs each time they are scheduled are allocated by the AN, because only the allocation by the AN can ensure that the transmission subcarriers used by each AT are orthogonal to each other. The reverse data transmission rate independently determined by the AT mainly refers to the spectral efficiency that the AT can achieve in the next transmission of packets, that is, the number of bits that can be transmitted per second per Hz per sector, corresponding to this determined reverse data transmission Spectrum efficiency AT should select the corresponding modulation and coding scheme (MCS: modulation and code scheme). In an OFDMA system, the spectral efficiency corresponds to the amount of data that can be transmitted by each subcarrier, and the higher the spectral efficiency, the more data transmitted per unit transmission unit.

In view of the above-mentioned ideas, the present invention proposes a method for determining the reverse data modulation and coding method here. The main realization principles, specific implementation methods and corresponding beneficial effects of the technical solution of the present invention will be described in detail below in conjunction with each accompanying drawing. .

As shown in Figure 1, it is a flow chart of the main realization principle of the method for determining the reverse data modulation and coding mode of the present invention, and its main realization process is as follows:

Step S10, in the wireless access network, the AT determines its own reverse power control reference channel according to the channel quality of the reverse power control reference channel indicated by the AN (the channel quality of the reverse power control reference channel can be based on the SNR identifier of the reverse power control reference channel) The channel quality of the data channel (correspondingly, the channel quality of the reverse data channel of the AT can also be based on the SNR mark); where the AT multiplies the channel quality of the reference channel based on the channel quality of the reference channel of the reverse power control indicated by the AN A predetermined offset value (Delta) is used as the channel quality of its own reverse data channel. In this process, the offset value (Delta) used by the AT is mainly determined by the transmission power of the AT reverse data channel relative to the reverse power. The gain of the transmission power of the control reference channel is determined, and at the same time, it is also limited by the maximum transmission power that the AT can actually support.

However, in the actual mobile communication system, although the channel quality (such as SNR) of the reference channel of the AT is maintained in a certain floating range due to the reverse power control effect of the AN on the AT, the actual channel quality of the reference channel of each AT is The quality (such as SNR) is not necessarily the same, and each AT may not be able to maintain the channel quality value of its own reference channel within the floating range, but may change according to the location of the AT and the interference it receives. It can be seen that each time the AT is scheduled, in order to enable the AT to calculate the accurate reverse data transmission rate, the actual channel quality of the reverse power control reference channel when the current AT performs reverse data transmission (such as SNR_of_BaseChannel when marked by SNR value) is based on the calculation, so as to ensure that the scheduling result and transmission rate calculated by the AT are optimal. However, AT does not know the channel quality value of the reverse power control reference channel at that time, so in the actual mobile communication system, AN can maintain the current reverse power control reference channel of AT at the same value through the overhead channel or in-band signaling. The channel quality value and its subsequent channel quality changes of the reverse power control reference channel are notified to the AT, and the AT can accurately calculate the value of its own reverse data according to the channel quality value of the reverse reference channel and its corresponding changes notified by the AN. The transfer rate is up.

In summary, the AN can accurately indicate the channel quality of the reverse power control reference channel to the AT through the following process:

The relevant adjustment step value is pre-agreed between AN and AT;

The AN periodically indicates the channel quality of the reverse power control reference channel measured by itself to the AT, and instructs the AT to increase or decrease the above agreed Step value; for example, when the AN measures that the frame error rate of the reverse data channel of the AT increases, it will instruct the AT to reduce the above agreed step value, and when the measured frame error rate of the reverse data channel of the AT decreases , will instruct AT to increase the above agreed step value;

According to the above instructions issued by the AN, the AT increases or decreases the agreed step value on the channel quality of the last received reverse power control reference channel, so that the AN can use the current accurate reference channel when scheduling the AT. The channel quality value is indicated to the AT, so that the AT can accurately determine the channel quality of its own reverse data channel based on the more accurate quality value of the reference channel, laying the foundation for subsequent accurate reverse data transmission rate, and this indication method can also Reduce excessive occupancy of forward overhead channel transmission resources.

For example, the SNR value of the channel is used to identify the channel quality of the channel. In the actual mobile communication system, the SNR_of_BaseChannel field of the reference channel can be carried in the way of in-band signaling. The value of this field is the AT reverse reference channel set by the system. The target SNR that needs to be maintained, because the in-band signaling can transmit more information, but the processing delay is relatively large, so the in-band signaling can use the SNR_of_BaseChannel field to be sent every certain period. At the same time, combined with the overhead channel indication method, such as A new overhead channel can be designed or an existing resource assignment channel can be used to carry the instruction information used to instruct AT to increase or decrease the adjustment step value. Since the overhead channel is characterized by fast processing speed, it cannot carry too much information , otherwise it will occupy too many transmission resources and affect the transmission of forward data. Therefore, 1 bit can be used here to identify the information instructing AT to increase or decrease the relevant adjustment step value. For example, the information indicated by AN to AT in the overhead channel is " When 0", it indicates that the AT is instructed to subtract the pre-agreed adjustment step value from the SNR value received by the latest in-band signaling mode, and when the information indicated by the AN to the AT in the overhead channel is "1", it indicates the indication The AT adds the pre-agreed adjustment step value to the last SNR value received through in-band signaling.

That is, the AN notifies the AT of the specific value of the SNR of the reference channel through in-band signaling every time, and transmits 1 bit information through the overhead channel to notify the AT of the change of the SNR of the reference channel, that is, the increase or decrease of the SNR of the reference channel. Decrease a certain step value, so that AT can quickly obtain the signal-to-noise ratio that can be maintained by the current reverse reference channel without occupying too much forward overhead, and the real-time performance of the notification is also very good. The specific time interval for sending the in-band signaling and the increased or decreased step size can be determined through pre-negotiation between the AN and the AT.

Step S20, the AT calculates the transmission spectral efficiency of its own reverse data according to the channel quality of the reverse data channel determined above (such as the SNR value of the reverse data channel), and can determine the frequency efficiency of the reverse data in the process of calculating the frequency efficiency of the reverse data. MCS information used for reverse data transmission.

Here AT determines the SNR value of its own reverse data channel according to the SNR value of the reference channel indicated by AN, and calculates the spectral efficiency of its own reverse data based on the determined SNR value of the reverse data channel, so as to calculate the reverse data spectrum In the process of efficiency, determine the MCS information used for reverse data transmission as an example to illustrate the calculation example of AT calculating the reverse data spectrum efficiency:

According to Shannon formula of information theory and "P.Hosein, "On the Optimal Scheduling of UplinkResources in OFDMA-Based Wireless Networks", Proceedings of the 12th European Wireless Conference, Athens, Greece, April 2006." document records, the present invention can be drawn here In an OFDMA system, the idealized spectral efficiency ρ=beta×log10(1+SNR), where SNR is the signal-to-noise ratio that can be obtained on a unit transmission unit (that is, the SNR value of the current reverse data channel), in actual mobile In the communication system, the spectral efficiency needs to be adjusted by a constant (beta), where the SNR in the formula is equal to:

$\mathrm{<span\; class="notranslate">\; SNR</span>}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; Data\; Power</span>}}{\mathrm{<span\; class="notranslate">\; Base\; Power</span>}}<span\; class="notranslate">\; \&times;</span>\mathrm{<span\; class="notranslate">\; SNR</span>}<span\; class="notranslate">\; \_</span>\mathrm{<span\; class="notranslate">\; of</span>}<span\; class="notranslate">\; \_</span>\mathrm{<span\; class="notranslate">\; BaseChannel</span>}$

正好等于上文提到的反向数据信道相对于基准信道的功率偏置值。即AT确定自身反向数据信道的SNR值时，要根据反向功控基准信道当前的SNR值，在其基础上乘以一偏置值得出，该偏置值还要受AT最大能够支持的发射功率控制。Where DataPower is the power value of the reverse data channel on the unit transmission unit, and BasePower is the power value of the reference channel on the unit transmission unit. The physical meaning of this formula is: when the power value on the base channel unit transmission unit is BasePower, the signal-to-noise ratio it can maintain is SNR_of_BaseChannel, then when the power value on the reverse data channel unit transmission unit is DataPower, the reverse data The signal-to-noise ratio that the channel can obtain is SNR. As can be seen

It is exactly equal to the power offset value of the above-mentioned reverse data channel relative to the reference channel. That is, when AT determines the SNR value of its own reverse data channel, it needs to multiply an offset value on the basis of the current SNR value of the reverse power control reference channel It can be concluded that the offset value is also controlled by the maximum transmit power that the AT can support.

After the SNR value of the reverse data channel is calculated by the above formula, the spectral efficiency that can be obtained by each AT reverse data channel can be obtained by calculating ρ=beta×log10(1+SNR), which may be required in an actual system Quantify and classify these spectral efficiencies, that is, summarize them into a limited number of rate levels. Finally, AT determines the corresponding reverse data transmission packet length according to the subcarrier resources allocated by AN to itself, that is, the actual transmission packet length PacketSize=ρ×T×N, where T is the transmission time of reverse data, and N is the number of subcarriers allocated by AN to AT. In the process of determining the frequency efficiency of reverse data in the above process, AT must find The corresponding set of MCS information is used as a way to modulate and encode the reverse transmission data, so that the coded and modulated reverse data can achieve a certain transmission spectral efficiency.

Subsequently, after the AT has determined the MCS information adopted for the reverse data transmission according to the above processing procedure, it can further combine the frequency resources indicated by the AN to itself (the AN can directly assign frequency resources to the AT on the forward assignment channel ), to further determine the transmission rate of its own reverse data; AT transmits data on the reverse data channel according to the determined reverse data transmission rate, and reports the MCS information determined according to the above process to the AN through the reverse rate indication channel ; In this way, the AN can perform corresponding demodulation and decoding processing on the reverse data transmitted by the AT according to the MCS information reported by the AT through the reverse rate indication channel, so as to complete the transmission processing of the uplink data. The specific processing process is shown in Figure 2 .

In addition, after the AT determines the MCS information adopted for the reverse data transmission, it can also realize the transmission processing of the uplink data through the following process, please refer to Figure 3 for details:

1. AT reports the determined MCS information used for reverse data transmission to AN through the reverse rate reporting channel;

2. The AN determines the frequency resources allocated to each AT according to the MCS information reported by each AT, and indicates the frequency resources allocated to each AT to the corresponding AT;

3. The AT determines the transmission rate of its own reverse data based on the determined MCS information used for reverse data transmission and combined with the frequency resources indicated by the AN to itself;

4. AT transmits data on the reverse data channel based on the reverse data transmission rate determined in 3 above;

5. The AN demodulates and decodes the reverse data transmitted by the AT according to the MCS information reported by the AT in the above 1, so as to complete the transmission process of the uplink data. Compared with the processing procedure in FIG. 2, the processing procedure in FIG. 3 is different in that the AT first reports the determined MCS information to the AN, and the AN determines the frequency resources allocated to the AT according to the MCS information reported by the AT, and then sends the determined MCS information to the AN. The frequency resources are indicated to the AT so that the AT can then determine the transmission rate of the reverse data.

In addition, in order to determine the transmission rate of the reverse data more accurately, after the AT determines the MCS information adopted for the reverse data transmission, the AT can also realize the transmission processing of the uplink data through the following process, please refer to Figure 4 for details :

1) AT reports the determined MCS information used for reverse data transmission to AN through the reverse rate reporting channel;

2) The AN determines the frequency resources allocated to each AT according to the MCS information reported by each AT, and reassigns new MCS information to each AT;

3) AN will indicate the frequency resources allocated to each AT and the new MCS information assigned to each AT to the corresponding AT;

4) The AT determines the transmission rate of its own reverse data based on the new MCS information indicated to itself by the AN and combined with the frequency resources indicated to itself by the AN;

5) AT transmits data on the reverse data channel based on the determined reverse data transmission rate;

6) The AN performs corresponding demodulation and decoding processing on the reverse data transmitted by the AT according to the corresponding MCS information assigned to the AT in the above 3), so as to complete the transmission processing of the uplink data.

In summary, the technical solution of the present invention can realize that in the process of AN scheduling AT, AT can autonomously calculate the spectrum efficiency used for reverse data according to the channel quality of the current reverse power control reference channel indicated by AN, and determine the corresponding The modulation and coding method adopted for the data. It is no longer necessary as in the prior art, the AT needs to report its own current power information, data size information to be sent, and QoS priority information to the AN, and then the AN determines the transmission rate that the AT needs to use to transmit the reverse data. Therefore, the scheduling error caused by the transmission delay of the uplink overhead information is avoided, and the AN can schedule the AT more accurately. At the same time, it also reduces the excessive occupation of the reverse transmission resources by the AT for reporting the relevant overhead information, and correspondingly improves The transmission throughput of the reverse transmission channel is improved.

Corresponding to the method proposed above in the present invention, the present invention also proposes an access terminal correspondingly here. Please refer to FIG. 5 for details. This figure is a specific structural block diagram of the access terminal proposed in the present invention, which mainly includes channel quality Determining unit 10 and modulation and encoding mode determining unit 20, wherein the specific functions of these two constituent units are as follows:

The channel quality determination unit 10 is used to determine the channel quality of the reverse data channel according to the channel quality of the reverse power control reference channel indicated by the AN in the wireless access network;

Modulation and coding mode determination unit 20, for determining the modulation and coding mode to be adopted for reverse data transmission according to the channel quality of the reverse data channel determined by above-mentioned channel quality determination unit 10 (that is, the MCS to be adopted for reverse data transmission) information).

Further, as shown in FIG. 6 , it is a block diagram of the specific composition and structure of the channel quality determination unit in the access terminal of the present invention, wherein the channel quality determination unit mainly includes a storage subunit 110, a channel quality cache subunit 120, a multiplication subunit 130, and a step size The value storage subunit 140, the indication information receiving subunit 150 and the step value adjustment subunit 160, wherein the specific functions of each component unit are as follows:

The storage subunit 110 is used to store an offset value in advance;

The channel quality cache subunit 120 is used to cache the channel quality of the reverse power control reference channel indicated by the AN last time;

The step value storage subunit 140 is used to store the pre-agreed adjustment step value between AN and AT;

The instruction information receiving subunit 150 is configured to receive the instruction information indicated by the AN to increase or decrease the agreed step size;

The step size adjustment subunit 160 is configured to increase or decrease the channel quality of the reverse power control reference channel buffered by the channel quality buffering subunit 120 by an agreed step size according to the indication information received by the indication information receiving subunit 150 value;

The multiplication subunit 130 is used to multiply the channel quality of the reverse power control reference channel currently buffered by the above-mentioned channel quality buffer subunit 120 and the offset value stored by the above-mentioned storage subunit 110, and use the multiplication result as the current reverse power control channel of the AT. Channel quality towards the data channel.

Please refer to FIG. 7 for details. This figure is a structural block diagram of the first embodiment for the access terminal to realize uplink data transmission according to the present invention. It further includes a first transmission rate determination unit 30 and a first transmission rate determination unit 30 on the basis of the main composition structure in FIG. A data transmission unit 40 and a first modulation and coding mode reporting unit 50, wherein the main functions of each newly added unit are as follows:

The first transmission rate determination unit 30 is configured to determine the transmission rate of the reverse data based on the MCS information used for the reverse data transmission determined by the above-mentioned modulation and coding method determination unit 20, in combination with the frequency resource conditions indicated by the AN;

The first data transmission unit 40 is configured to transmit data on the reverse data channel according to the reverse data transmission rate determined by the first transmission rate determination unit 30;

The first modulation and coding mode reporting unit 50 is used to report the MCS information adopted by the modulation and coding mode determination unit 20 for reverse data transmission to the AN, so that the AN can report the MCS according to the first modulation and coding mode reporting unit 50 The relevant demodulation and decoding processing is performed on the reverse data transmitted from the first data transmission unit 40 .

In addition, the above-mentioned first modulation and coding method reporting unit 50 can also first report the MCS information used for the reverse data transmission determined by the modulation and coding method determination unit 20 to the AN, and the AN further provides information for each AT according to the MCS information adopted by each AT. Allocate corresponding frequency resources, and indicate the allocated frequency resources to the corresponding AT; the first transmission rate determination unit 30 further bases on the MCS information used for reverse data transmission determined by the above-mentioned modulation and coding method determination unit 20, combined with AN Determine the transmission rate of the reverse data according to the indicated frequency resource situation; the first data transmission unit 40 then transmits data on the reverse data channel according to the reverse data transmission rate determined by the first transmission rate determination unit 30; in this way, the AN can also According to the MCS information reported by the first modulation and coding mode reporting unit 50, the reverse data transmitted from the first data transmission unit 40 is subjected to relevant demodulation and decoding processing.

Further please refer to FIG. 8 , which is a structural block diagram of the second embodiment of the present invention for the access terminal to realize uplink data transmission, which further includes a second modulation and coding mode reporting unit 60, The second transmission rate determination unit 70 and the second data transmission unit 80, wherein the specific functions of each constituent unit are as follows:

The second modulation and coding method reporting unit 60 is configured to report the MCS information used for the reverse data transmission determined by the modulation and coding method determination unit 20 to the AN;

The second transmission rate determination unit 70 is configured to determine the transmission rate of reverse data based on the new MCS information indicated by the AN and the allocation of frequency resources;

The second data transmission unit 80 is configured to transmit data on the reverse data channel according to the reverse data transmission rate determined by the second transmission rate determination unit 70, so that the AN can transmit the new MCS information to the AT according to the new MCS information indicated by itself to the AT. The reverse data transmitted from the second data transmission unit 80 is subjected to relevant demodulation and decoding processing.

In addition, for the implementation details of other related specific technologies related to the access terminal of the present invention, please refer to the relevant description in the above-mentioned method of the present invention, and no more details are given here.

Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention also intends to include these modifications and variations.

Claims (17)

1. A method for determining reverse data modulation and coding mode, characterized in that, comprising steps: In the wireless access network, the access terminal determines the channel quality of its own reverse data channel according to the channel quality of the reverse power control reference channel indicated by the access network; and According to the determined channel quality of the reverse data channel, the modulation and coding mode adopted for the reverse data transmission is determined. 2. The method according to claim 1, wherein the process of the access network indicating the channel quality of the reverse power control reference channel to the access terminal specifically includes: The adjustment step value is pre-agreed between the access network and the access terminal; The access network periodically indicates the measured channel quality of the reverse power control reference channel to the access terminal; and Instructing the access terminal to increase or decrease the agreed step value according to the change of the channel quality of the reverse data channel of the access terminal during the period when the channel quality is not indicated; The access terminal increases or decreases the agreed step value on the channel quality of the last received reverse power control reference channel according to the instruction of the access network. 3. The method according to claim 2, wherein the access network instructs the access terminal to increase or decrease the agreed step value according to the channel quality change of the reverse data channel, specifically refers to: When the access network measures an increase in the frame error rate of the reverse data channel of the access terminal, instruct the access terminal to decrease the agreed step value; and Instructing the access terminal to increase the agreed step value when the frame error rate of the reverse data channel of the access terminal is measured to decrease. 4. The method according to claim 1, 2 or 3, wherein the access terminal multiplies the channel quality of the reverse power control reference channel indicated by the access network by a predetermined offset value as its own reverse data The channel quality of the channel. 5. The method according to claim 4, wherein the predetermined offset value is transmitted by the unit transmission unit transmission power of the reverse data channel of the access terminal relative to the unit transmission unit transmission unit of the reverse power control reference channel Power gain is determined. 6. The method of claim 1, further comprising the steps of: The access terminal determines its own reverse data transmission rate based on the determined modulation and coding scheme adopted for reverse data transmission and in combination with frequency resources indicated to itself by the access network. 7. The method of claim 6, further comprising the steps of: the access terminal transmits data on the reverse data channel based on the determined reverse data transmission rate; and Report the determined modulation and coding method used for reverse data transmission to the access network; The access network demodulates and decodes the reverse data transmitted by the access terminal according to the modulation and coding mode reported by the access terminal. 8. The method of claim 1, further comprising the steps of: The access terminal reports the determined modulation and coding method adopted for reverse data transmission to the access network; The access network determines frequency resources allocated to each access terminal according to the modulation and coding scheme reported by each access terminal; and Indicating the frequency resource allocated to each access terminal to the corresponding access terminal respectively; The access terminal determines its own reverse data transmission rate based on the determined modulation and coding scheme adopted for reverse data transmission and in combination with frequency resources indicated to itself by the access network. 9. The method of claim 8, further comprising the steps of: the access terminal transmits data on the reverse data channel based on the determined reverse data transmission rate; The access network demodulates and decodes the reverse data transmitted by the access terminal according to the modulation and coding mode reported by the access terminal. 10. The method of claim 1, further comprising the steps of: The access terminal reports the determined modulation and coding method adopted for reverse data transmission to the access network; The access network determines frequency resources allocated to each access terminal according to the modulation and coding scheme reported by each access terminal; and Re-assign a new modulation and coding method for each access terminal; The access network will indicate the frequency resources allocated to each access terminal and the new modulation and coding scheme assigned to each access terminal to the corresponding access terminal; The access terminal determines its reverse data transmission rate based on the new modulation and coding scheme indicated by the access network and in combination with the frequency resources indicated by the access network. 11. The method of claim 10, further comprising the steps of: the access terminal transmits data on the reverse data channel based on the determined reverse data transmission rate; The access network demodulates and decodes the reverse data transmitted by the access terminal according to the corresponding modulation and coding mode assigned to the access terminal. 12. The method of claim 4, wherein the channel quality of the channel is identified based on a signal-to-noise ratio of the channel. 13. An access terminal, comprising: The channel quality determining unit is used to determine the channel quality of the reverse data channel according to the channel quality of the reverse power control reference channel indicated by the access network in the wireless access network; The modulation and coding mode determining unit is used to determine the modulation and coding mode adopted for the reverse data transmission according to the channel quality of the reverse data channel determined by the channel quality determining unit. 14. The access terminal according to claim 13, wherein the channel quality determining unit specifically comprises: The storage subunit is used to store an offset value in advance; The channel quality caching subunit is used to cache the channel quality of the reverse power control reference channel indicated by the access network last time; The multiplication subunit is used to multiply the channel quality of the reverse power control reference channel buffered by the channel quality buffer subunit by the offset value stored in the storage subunit, and use the multiplication result as the channel quality of the reverse data channel. 15. The access terminal according to claim 14, wherein the channel quality determination unit specifically further comprises: The step value storage subunit is used to store the pre-agreed adjustment step value between the access network and the access terminal; An indication information receiving subunit, configured to receive indication information indicated by the access network to increase or decrease the agreed step value; The step size adjustment subunit is configured to increase or decrease the agreed step size value according to the indication information received by the indication information receiving subunit to increase or decrease the channel quality of the reverse power control reference channel buffered by the channel quality buffering subunit. 16. The access terminal of claim 13, further comprising: The first transmission rate determination unit is configured to determine the transmission rate of the reverse data based on the modulation and coding method adopted for the reverse data transmission determined by the modulation and coding method determination unit, in combination with the frequency resources indicated by the access network; The first data transmission unit is configured to transmit data on the reverse data channel according to the reverse data transmission rate determined by the first transmission rate determination unit; The first modulation and coding method reporting unit is configured to report the modulation and coding method used for reverse data transmission determined by the modulation and coding method determining unit to the access network. 17. The access terminal of claim 13, further comprising: The second modulation and coding method reporting unit is used to report the modulation and coding method used for the reverse data transmission determined by the modulation and coding method determination unit to the access network; The second transmission rate determination unit is configured to determine the transmission rate of reverse data based on the new modulation and coding scheme and frequency resources indicated by the access network; The second data transmission unit is configured to transmit data on the reverse data channel according to the reverse data transmission rate determined by the second transmission rate determination unit.

Images