WO2005025090A1

WO2005025090A1 - Radio transmitting apparatus and radio transmitting method

Info

Publication number: WO2005025090A1
Application number: PCT/JP2004/012922
Authority: WO
Inventors: Yuichi Hagiwara
Original assignee: Matsushita Electric Industrial Co., Ltd.
Priority date: 2003-09-02
Filing date: 2004-08-31
Publication date: 2005-03-17
Also published as: JP2005080115A

Abstract

An RV pattern selecting part (102) has stored therein at least two RV parameter tables for QPSK and for 16QAM, selects, based on the correspondence between an estimated number of transmissions inputted from a number-of-transmissions estimating part (101) and an input Doppler frequency (fD) as estimated from a transmission signal, a corresponding RV parameter (Xrv) (e.g., RV&lowbar;a&lowbar;T1) from the RV parameter tables, and outputs the selected RV parameter to a channel encoding part (103). In this way, an RV parameter, which corresponds to an appropriate number of transmissions with the affection of the Doppler frequency taken into account, can be set, and further, a transmission bit pattern corresponding to a change in the Doppler frequency of the transmission signal can be set, whereby the number of transmissions can be reduced.

Description

Description Wireless transmission device and wireless transmission method

The present invention relates to a wireless transmission device and a wireless transmission method. Background technology ''

Conventionally, HSDPA (High Speed Downlink Packet Access) has been used as a high-speed bucket transmission scheme of the W-CDMA (Wideband Code Division Multiple Access) scheme. HSD PA adopts HARQ. HARQ (Hybrid Automatic ReQuest) is a method that combines retransmission control (ARQ: Automatic ReQuest) and error correction coding.

The HSDPA-compatible base station employs the “HARQ function” shown in step S 17 in the transmission data processing flowchart shown in FIG. The data to be transmitted is subjected to turbo coding with a coding rate of 1-3, and the HARQ function changes the rate to match the number of physical channel bits actually transmitted.

The hardware configuration of the HARQ function is configured as shown in the block diagram of FIG. 2. In the second rate matching unit 54, what bits are transmitted using the systematic priority parameter s and the rate matching parameter r Has been determined.

That is, in the second rate matching unit 54, each data of Systematic (hereinafter, referred to as “systematic”), Parityl, and Parity2 (hereinafter, referred to as “parity 1” and “parity 2”) included in the turbo-coded transmission data It determines how to perform rate matching (matching to the actual number of physical channels) for transmission.

For example, systematic data transmission priority or parity 1, 2 transmission priority, It also determines the pattern in which the bits of parity 1 and 2 are thinned out (or repeated).

By changing the systematic priority parameter s and the rate matching parameter + parameter r in this way, it is possible to transmit different transmission bit patterns at the time of initial transmission and at the time of retransmission, making it easier to obtain coding gain. Can be.

In addition, HSDPA-compatible base stations adopt the Constellation Rearrangement di. Phase rearrangement when the modulation method is 16 QAM (Quadrature Amplitude Modulation).

In this case, the constellation relocation parameter b that changes the constellation of 16 QAM is used as shown in the 16 QAM relocation processing in step S20 in FIG. The gain from the rearrangement of chillons is obtained.

In the HSD PA-compatible base station, two HARQ parameters (systematic priority parameter s, rate matching parameter r) and constellation relocation parameter b are given Ry (Redundancy version) parameter, and The transmission bits are determined by changing the rate matching pattern and constellation rearrangement (applied to 16 QAM only).

Tables 1 and 2 show examples of setting the RV parameter Xrv when the modulation scheme is QP SK and 16 Q AM in the HSDPA compatible base station.

[table 1]

[Table 2] Xrv (value) srb

0 1 0 0

1 0 0 0

2 1 1 1

3 0 1 1

4 1 0 1

5 1 0 2

6 1 0 3

7 1 10 Table 1 shows the setting value of the RV parameter Xrv of QP SK based on the 3GPP TS25.212 standard, and Table 2 shows the setting value of the RV parameter Xrv of 16QAM based on the 3GPP TS25.212 standard.

In Tables 1 and 2, when the systematic priority parameter s = 1, transmission of systematic data takes precedence, and when systematic priority parameter s = 0, transmission of parity data 1 and 2 takes precedence. You.

Conventionally, as described in 3GPP.TS25.101, transmission is performed by defining an RV parameter for each transmission count as shown in Tables 3 and 4.

3]

[Table 4]

However, as described in the conventional 3GPP TS25.101, and as shown in Tables 3 and 4, only the RV parameter is determined for each transmission count according to the modulation method and transmission is performed. Since the RV parameter was not changed for the change in the Doppler frequency in the above, there was a problem that the transmission could not be performed using the RV parameter for the appropriate number of transmissions taking into account the influence of the Doppler frequency. Disclosure of the invention

An object of the present invention is to reduce the number of retransmissions by setting an RV parameter for an appropriate number of transmissions in consideration of the influence of the Doppler frequency, enabling setting of a transmission bit pattern corresponding to a change in the Doppler frequency in a transmission signal. It is an object of the present invention to provide a radio transmission device and a radio transmission method that can perform the above.

The purpose of this is to set the RV parameter for the appropriate number of transmissions taking into account the effect of the Doppler frequency, to enable the setting of the transmission bit pattern corresponding to the change in the Doppler frequency in the transmission signal from the terminal, and to reduce the number of retransmissions. This can be achieved by reducing it. Brief Description of Drawings

FIG. 1 is a flowchart showing transmission data processing in a conventional HARQ-compatible base station.

FIG. 2 is a block diagram showing the configuration of a HARQ function unit of a conventional HARQ-compatible base station,

FIG. 3 is a block diagram illustrating a main configuration of a transmitting apparatus according to Embodiment 1 of the present invention. FIG. 4 is a diagram illustrating an example of an RV parameter table used in the transmitting apparatus according to Embodiment 1.

FIG. 5 is a block diagram illustrating a main configuration of a transmitting apparatus according to Embodiment 2 of the present invention, and FIG. 6 is a diagram illustrating an example of an RV parameter table used in the transmitting apparatus according to Embodiment 2.

FIG. 7 is a block diagram illustrating a main configuration of a transmitting apparatus according to Embodiment 3 of the present invention, and FIG. 8 is a diagram illustrating an initial state of an RV estimation transmission count section in the transmitting apparatus according to Embodiment 3. The figure of the

FIG. 9A is a diagram for explaining the operation of the RV estimation transmission count section in the transmitting apparatus according to Embodiment '3.

FIG. 9B illustrates the operation of the estimated RV transmission count section in the transmitting apparatus according to Embodiment 3. Figure for clarification,

FIG. 9C is a diagram for explaining the operation of the RV estimation transmission count section in the transmitting apparatus according to Embodiment 3.

FIG. 9D is a diagram for explaining the operation of the RV estimation transmission count section in the transmitting apparatus according to Embodiment 3, and

FIG. 10 is a diagram showing an example of an RV parameter table used in the transmitting apparatus according to Embodiment 3. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(Embodiment 1)

FIG. 3 is a block diagram showing a main configuration of an HSDPA compatible transmission apparatus according to Embodiment 1 of the present invention.

Transmitting apparatus 100 mainly includes transmission number estimating section 101, RV pattern selecting section 102, and channel coding section 103.

The transmission count estimator 101 includes an Ack (Acknowledgment) / Nack (Negative Acknowledgment) signal from an uplink HS-DPCCH (High Speed-Dedicated Physical Channel) received from a receiving terminal (not shown), and a transmission 1 The number of transmissions that could have been transmitted to the receiving terminal is estimated based on the number of times, and the estimated number of transmissions is output to the RV pattern selection unit 102.

The transmission count estimating unit 1◦1 increases the transmission estimation count by one when the Nack signal is received and outputs it.If the Ack / Nack signal cannot be received at the expected reception timing, the transmission is successful. Since it seems to have failed, output without increasing the estimated number of transmissions.

The RV pattern selection unit 102 stores at least two RV parameter tables for QPSK and 16 QAM as shown in FIG. 4, and the estimated number of transmissions input from the transmission number estimation unit 101 And the transmission signal from the terminal received by the base station Based on the relationship between the estimated and input Dobbler frequency f D and the corresponding RV parameter Xrv (for example, RV_a_T 1) from the RV parameter table, it is output to the channel coding unit 103.

The RV parameter table shown in Fig. 4 divides the frequency band of the Doppler frequency i D into three ranges (0≤f <fl, f1≤f <f2, f2≤f≤f3), and The RV parameter Xrv (Doppler frequency fD: 0≤f <f1: RV_a_T1,..., RV—a—TN, etc.) is set for each estimated number of transmissions within the range of the Doppler frequency fD. The parameters corresponding to QPSK and 16 QAM shown in Tables 1 and 2 above are set in these RV parameters Xrv.

The channel encoding unit 103 performs a channel encoding process based on the RV parameter Xrv input from the RV pattern selection unit 102, and performs rate matching pattern and constellation rearrangement (16 QAM) of input transmission data. (Applicable only to the above) Transmit the changed transmission bit as HS—DSCH (High Speed-Downlink Shared Channel).

As described above, according to the transmitting apparatus of the present embodiment, it is possible to retransmit the transmission data by setting the RV parameter for the appropriate number of transmissions in consideration of the influence of the Doppler frequency in the transmission signal. Can be reduced.

(Embodiment 2)

FIG. 5 is a block diagram showing a main configuration of HSDPA-compatible transmitting apparatus 200 according to Embodiment 2 of the present invention. Transmitting apparatus 200 differs from the first embodiment in that RV pattern is selected not only by Doppler frequency but also by coding rate (including modulation scheme).

Transmitting apparatus 200 mainly includes transmission number estimating section 201, coding rate calculating section 202, RV pattern selecting section 203, and channel coding section 204, and power. Here, transmission number estimation section 201 and channel coding section 204 have the same functions as transmission number estimation section 101 and channel coding section 103 shown in Embodiment 1, and therefore description thereof will be omitted. The coding rate calculation unit 202 assumes that the modulation scheme and the number of codes are constant during the first transmission and the retransmission, and that the transmission data, the number of transmissions, the number of codes, and the modulation scheme (for example, The coding rate is calculated based on QPSK or 16QAM), and the calculated coding rate is output to RV pattern selecting section 203. It is assumed that the coding rate calculation unit 202 calculates the coding rate only at the time of the first transmission.

The RV pattern selection unit 203 stores at least two RV parameter tables as shown in FIG. 6 for QPSK and 16QAM, and calculates the modulation scheme, the estimated transmission number input from the transmission number estimation unit 201, Based on the correspondence between the Doppler frequency fD estimated and input at the time of transmission and the coding rate input from the coding rate calculation unit 202, the corresponding RV parameter Xrv (for example, , RV—fl_a_T 1) are selected and output to the channel encoder 204.

The RV parameter table shown in Fig. 6 divides the frequency band of the Doppler frequency f D into two ranges (f D f (f 1), f (f 1) ≤ ί D), and sets the coding rate. It is divided into three ranges (O x x xl, X 1 ≤ <X 2, x 2 xl), and the RV parameter Xrv (Doppler frequency f D <f (f 1), coding rate 0≤x <xl: RV_a_T 1, ■. ·, RV—a—ΤΝ, etc.). These RV parameters Xrv are as shown in Table 1 above. The parameters corresponding to QPS and 16 QAM shown in Table 2 are set.

Thus, according to the transmitting apparatus of the present embodiment, the RV parameter for the appropriate number of transmissions corresponding to the Doppler frequency and the coding rate at the time of the first transmission of transmission data is set, and the transmission data is retransmitted. And the number of retransmissions can be reduced.

(Embodiment 3)

FIG. 7 is a block diagram of transmitting apparatus 300 for HSDPA according to Embodiment 3 of the present invention. It is a block diagram which shows a part structure. The transmitter 300 always calculates the coding rate for each number of transmissions, and if the number of transmission codes changes and the coding rate changes significantly or if the modulation method is changed, the Doppler frequency may change significantly. Embodiment 2 is different from Embodiment 2 in that it is possible to cope with the case, and that the RV parameter is selected based on the Doppler frequency, the modulation scheme, and the coding rate even during retransmission.

The transmitting apparatus 300 includes a transmission number estimation section 301, an RV estimation transmission number section 302, a coding rate calculation section 303, an RV pattern selection section 304, and a channel encoding section 300. Mainly composed of

The transmission number estimation unit 301, the coding rate calculation unit 303, and the channel encoding unit 300 include the transmission number estimation unit 101 described in Embodiment 1 and the coding described in Embodiment 2. Since it has the same function as the rate calculator 202 and the channel encoder 103 shown in the first embodiment, description thereof will be omitted.

The RV estimation transmission number section 302 includes an input modulation scheme, an estimated transmission number input from the transmission number estimation section 301, a Doppler frequency fD estimated and input at the time of transmission, and coding. Based on the coding rate input from rate calculating section 303, the number of estimated RV transmissions shown in FIGS. 8 and 9 is set and output to RV pattern selecting section 304.

FIG. 8 shows a case of the initial state before transmission, and the number of RV estimation transmissions is all “0” regardless of the modulation scheme and the coding rate. 9A to 9D show the settings of the estimated number of RV transmissions at the time of the first transmission after the transmission is started, the first retransmission, the second retransmission, and the third retransmission.

Figure 9A shows the setting of the number of RV estimation transmissions at the time of the first transmission. When the modulation method is QPSK :, the Doppler frequency (fP f1), and the coding rate (0≤x <x1), The number of estimated RV transmissions is “1”. Next, at the time of the first retransmission shown in FIG. 9B, in the case of the same Dobbler frequency ΔD, coding rate, and modulation scheme as at the time of the first transmission, the number of RV estimation transmissions is incremented to “2”. Next, at the second retransmission shown in Fig. 9C, only the retransmission and the Doppler frequency ί D differ from f 1 ≤ f D In this case, the corresponding RV transmission count is set to “1”. Then, when shown to the third retransmission in FIG. 9D, if the retransmission by the second and a coding rate is different from the _{_X} 1≤ _{X <X} 2 is a RV estimated transmission number and its corresponding "1".

The RV pattern selection unit 304 stores at least two RV parameter tapes for QP SK and 16QAM as shown in FIG. 10, the modulation method, and the RV estimation transmission input from the RV estimation transmission number unit 302. Based on the correspondence between the number of times, the Doppler frequency f D estimated and input at the time of transmission, and the coding rate input from the coding rate calculation unit 303, the corresponding RV parameter Xrv ( For example, RV—fl_a_T 1) is selected and output to the channel coding unit 305.

Therefore, in the transmitting apparatus according to the present embodiment, even when the number of transmission codes changes and the coding rate greatly changes, when the modulation method is changed, and when the Doppler frequency greatly changes, the transmission data can be transmitted. By setting the RV parameter for the appropriate number of transmissions corresponding to the Doppler frequency and the code rate, transmission data can be retransmitted, and the number of retransmissions can be reduced.

As described above, according to the transmitting apparatuses of Embodiments 1 to 3 to which the present invention is applied, the RV parameter for the appropriate number of transmissions considering the influence of the Doppler frequency is set, and the change of the Doppler frequency in the transmitted signal is changed. Since it is possible to set the transmission bit pattern corresponding to, the number of retransmissions can be reduced.

For example, when the coding rate is close to 1 and the Dobler frequency is high, when the systematic bits of the Turbo code are transmitted, it may not be transmitted to the receiving terminal device side. In such a case, in the decoding process on the receiving terminal side, the systematic bit becomes large information. In this case, by applying the present invention, it is possible to cope with the case where the Doppler frequency is high, such as sending a larger number of systematic bits than when the Doppler frequency is low. It becomes possible to reduce the number of retransmissions as compared with the case where there is no retransmission.

This description is based on Japanese Patent Application No. 2003-310551 filed on Sep. 2, 2003. It is a spider. This content is included here.

Industrial applicability

The present invention relates to a radio transmission apparatus and a radio transmission method, and is particularly suitable for use in a radio transmission apparatus and a radio transmission method of a hybrid ARQ scheme for retransmitting transmission data to a reception apparatus.

Claims

The scope of the claims

1. In a wireless transmission device of the hybrid ARQ scheme for retransmitting transmission data to the receiving device based on a retransmission request from the receiving device, the number of transmissions for estimating the number of transmissions based on the retransmission request from the receiving device An estimating unit, a selecting unit that selects a retransmission parameter according to the Doppler frequency based on the estimated number of transmissions estimated by the transmission number estimating unit, and a Doppler frequency estimated from a transmission signal; And a coding unit for coding the transmission data based on the selected retransmission parameter to generate retransmission data.

2. A transmission count for estimating the number of transmissions based on a retransmission request from the receiving device in a hybrid ARQ wireless transmission device that retransmits transmission data to the receiving device based on a retransmission request from the receiving device. An estimating unit, a coding rate calculating unit that calculates a coding rate based on a set modulation scheme, transmission data, and the number of codes at the time of the first transmission; the estimated number of times of transmission; Based on the set modulation scheme, the Doppler frequency of the transmission signal estimated at the time of the first transmission, and the coding rate calculated by the coding rate calculating means, retransmission according to the Doppler frequency and the coding rate Selecting means for selecting a trust parameter; and a code for coding the transmission data to generate retransmission data based on the retransmission parameter selected by the selection means. A wireless transmission device, comprising:

3. The number of transmissions for estimating the number of transmissions based on a retransmission request from the receiving device in a hybrid ARQ wireless transmission device that retransmits transmission data to the receiving device based on a retransmission request from the receiving device. Estimating means, coding rate calculating means for calculating a coding rate based on the set modulation method, transmission data, and number of codes, the set modulation method, and the number of transmissions estimating means. A retransmission parameter based on the determined estimated number of transmissions, the coding rate calculated by the coding rate calculating means, and the Doppler frequency of the transmission signal estimated at the time of transmission. Transmission number setting means for setting an estimated transmission number for use; an estimated transmission number set by the estimated transmission number setting means; the set modulation scheme; the Doppler frequency; and the coding rate calculating means. Based on the coding rate calculated by! /, And, based on the retransmission parameter selected by the selecting means, selecting means for selecting a retransmission parameter corresponding to the Doppler frequency and the coding rate, And a coding means for coding transmission data to generate retransmission data.

4. In the wireless transmission method of the hybrid ARQ scheme in which transmission data is retransmitted to the receiving device based on a retransmission request from the receiving device, the number of transmissions is estimated based on the retransmission request from the receiving device. An estimating step, a selecting step of selecting a retransmission parameter according to the Doppler frequency based on the estimated number of times of transmission and a Doppler frequency estimated from a transmission signal, and based on the selected retransmission parameter. And a coding step of coding the transmission data to generate retransmission data.

5. In the wireless transmission method of the hybrid ARQ scheme for retransmitting transmission data to the receiving device based on a retransmission request from the receiving device, the number of transmissions for estimating the number of transmissions based on the retransmission request from the receiving device An estimating step, a coding rate calculating step of calculating a coding rate based on a set modulation scheme, transmission data, and the number of codes at the time of the first transmission; Based on the set modulation scheme, the Doppler frequency of the transmission signal estimated at the time of the first transmission, and the calculated coding rate, selection for selecting a retransmission parameter corresponding to the Doppler frequency and the code rate. And an encoding step of encoding the transmission data based on the selected retransmission parameters to generate retransmission data. A wireless transmission method characterized by the above-mentioned.

6. In a wireless transmission method of the hybrid ARQ scheme for retransmitting transmission data to the receiving device based on a retransmission request from the receiving device, A transmission number estimation step of estimating the number of transmissions based on the retransmission request of the above, a coding rate calculation step of calculating a coding rate based on the set modulation scheme, transmission data and the number of codes, Based on the set modulation scheme, the estimated number of transmissions, the calculated coding rate, and the Doppler frequency of the transmission signal estimated at the time of transmission, an estimated number of transmissions for a retransmission parameter is calculated. Setting the estimated number of transmissions to be set, the set estimated number of transmissions, the set modulation method, the Doppler frequency, and the calculated coding rate, based on the Doppler frequency and coding. A selecting step of selecting a retransmission parameter according to a rate; and encoding the transmission data based on the selected retransmission parameter to generate retransmission data. And a coding step.