CN102064924A - Relaying method for uplink data retransmission and mobile communication system - Google Patents

Abstract

The invention provides a relaying method for uplink data retransmission and a mobile communication system. The transparent relaying method comprises the following steps: a base station receives uplink data, a first reference signal and control information embedded into the uplink data, which are retransmitted on a first resource by a user terminal based on a NACK (Negative Acknowledgement) signal; the base station receives the uplink data or the precoded uplink data and a second reference signal, which are transmitted on the first source by a relaying station based on the ANCK signal, wherein the second reference signal is different from the first reference signal; and the base station calculates channel response by utilizing the first reference signal, the second reference signal and the received signals and detects the control information and the uplink data by using the calculation result of channel response. According to the invention, cooperative diversity gain is obtained on the basis of correctly transmitting the control information and the uplink data.

Description

Trunking method and mobile communication system during a kind of uplink data retransmission

Technical field

The present invention relates to the transparent relay technical field, trunking method and relay station during particularly a kind of uplink data retransmission.

Background technology

The flow process that transparent relay is used for auxiliary uplink data retransmission comprises as shown in Figure 1:

Step 11, user terminal sends upstream data to the base station; Because the opening of wireless channel, relay station also can receive the upstream data and the control information of user terminal.Because relay station distance users terminal is nearer usually,, relay station is greater than the base station so successfully receiving the probability of user terminal data;

Step 12, the base station is detected the upstream data that the user terminal that receives sends, if correct, then feeding back ACK is given user terminal, if incorrect, then feed back NACK and gives user terminal;

Step 13, user terminal retransmit upstream data after receiving the NACK signal of base station.

In this case, relay station can be used for the re-transmission of assist user terminal data, i.e. the ack/nack signal of relay station monitoring base station and obtain the resource location information that user terminal is used for data re-transmission.When user terminal carried out data re-transmission, relay station sent identical data simultaneously on identical resource, to obtain the collaboration diversity gain.

Because the position of relay station is through optimizing, so common relay station is better than the channel of user terminal to base station to the channel of base station.Because relay station auxiliary, the data of re-transmission will be improved greatly by the correct probability that receives in base station like this.

But when said method is used for LTE (Long Term Evolution, Long Term Evolution) and LTE-A (long term evolution-Advanced, advanced Long Term Evolution) system, can there be certain problem, be described below.

LTE system requirements user is when carrying out the upstream data transmission, if control information is arranged, then control information will be embedded in the data channel and send, and that is to say, in step 11, user terminal need be embedded in control information A1 in the upstream data and send simultaneously.And in step 13, user terminal need be embedded in control information A2 and send (just append in the data and send) in the data simultaneously.If relay station sends the upstream data that user terminal sends in step 11 in step 13, the base station can receive the control signal of two stacks, promptly from the control signal A2 of user terminal with from the control signal A1 of relay station, the base station can't correctly detect control information 2, even relay station is to the control information A1 that user terminal sends in step 11 punching (promptly to control information A1 residing position zero setting), and then in step 13, send, the base station still has problem to the detection of user terminal control signal A2.Because user terminal and relay station all need to send reference signal, so the base station can estimate the channel response of a stack when channel estimating, promptly the channeling and trunking station of user terminal to base station is to the stack of the channel response of the channel of base station.Yet, for control information A2, because have only user terminal to send, so the channel that its real channel response is a user terminal to base station.If control information A2 is removed to detect with the channel of the stack that estimates in the base station, then detecting performance can non-constant.

And for the LTE-A system, its user terminal has two kinds of patterns.A kind of is user terminal when having upstream data to send, and still can take control channel and be used to send control information.A kind of is user terminal when having upstream data to send, and control information must be embedded in the data channel.User terminal adopts any pattern by base station configuration.If user terminal is configured to a kind of pattern in back, then exist and the same problem of LTE system.

In order to address this problem, two schemes are arranged at present, as follows.

Scheme one (Always PHICHACK) as shown in Figure 2, comprising:

Step 21, user terminal sends upstream data to the base station; Because the opening of wireless channel, relay station also can receive the upstream data and the control information of user terminal.Because relay station distance users terminal is nearer usually,, relay station is greater than the base station so successfully receiving the probability of user terminal data;

Step 22 no matter whether the upstream data that the user terminal that the base station receives sends correctly all sends ACK to user terminal, and sends NACK to relay station when the upstream data of the user terminal transmission that receives is incorrect;

Step 23, after user terminal received ack signal, it was correct to think that data in the step 21 send, data retransmission signal not then, A2 only sends control information in ascending control channel; Because control channel has the reference signal of oneself, so control information A2 can correctly be detected in the base station.

After step 24, relay station received the NACK signal, the upstream data that retransmits its user terminal that receives transmission was to the base station.

Yet there are the following problems at least for such scheme:

Need new signaling, because the ACK that the base station sends in step 22 can not reflect the base station and whether correctly receive the data of user terminal, after so relay station monitors this ACK, whether need retransmit, so whether the base station also needs new signaling to notify the relay station data really correctly to receive if can not determine.

Expendable re-transmission mistake, user terminal is after receiving ACK, can empty the data in the own buffer memory, and if relay station does not correctly receive the data of user terminal, even the re-transmission carried out again repeatedly of relay station can not recover original correct data so;

Need take uplink control channel resource, user terminal needs the outer control channel resource of the occupying volume A2 that sends control information;

There is not the collaboration diversity gain, because have only relay station, so can not obtain the collaboration diversity gain in the re-transmission of carrying out data.

Scheme two (Fujitsu's scheme) as shown in Figure 3, comprising:

Step 31, user terminal sends upstream data to the base station; Because the opening of wireless channel, relay station also can receive the upstream data and the control information of user terminal.Because relay station distance users terminal is nearer usually,, relay station is greater than the base station so successfully receiving the probability of user terminal data;

Step 32, the base station is detected the upstream data that the user terminal that receives sends, if correct, then feeding back ACK is given user terminal, if incorrect, then feed back NACK and gives user terminal;

Step 33, user terminal retransmit upstream data after receiving the NACK signal of base station;

Step 34, the signal of the user terminal that relay station receives oneself detects, if find that the signal that receives is correct, then sends ack signal to the base station;

After step 35, base station received the ack signal of relay station, whether the data of the user terminal that no matter receives detected correctly, all sent ack signal to user terminal, in re-transmission subsequently, then had only relay station to retransmit.

Scheme two " expendable re-transmission is wrong " problem in can solution one does not as can be seen need the resource of control channel yet.

Yet still there is following shortcoming in scheme two:

Need extra signaling, for example, whether relay station must be reported the data of the user terminal that oneself receives to the base station correct.

There is not the collaboration diversity gain, because have only user terminal or relay station to retransmit, so can not obtain the collaboration diversity gain.

In addition, when the relatively poor and relay station of the channel of user terminal to base station was better to the channel of base station, the scheme of Fujitsu was because the re-transmission of priority user terminal, so can cause the correct receive time delay of bigger data usually.

Summary of the invention

Trunking method and relay station when the purpose of this invention is to provide a kind of uplink data retransmission are used for LTE system or LTE-A system, make uplink data retransmission have the collaboration diversity gain.

To achieve these goals, the trunking method the when embodiment of the invention provides a kind of uplink data retransmission comprises:

Upstream data, first reference signal that base station reception user terminal resends on first resource based on the NACK signal and the control information that is embedded into described upstream data;

The base station receives the upstream data after relay station carries out precoding based on described NACK signal at the upstream data that sends on described first resource or with described upstream data, and second reference signal; Described second reference signal is different with described first reference signal;

The calculated signals channel response that the base station utilizes described first reference signal, second reference signal and receives, and utilize the result of calculation of described channel response to detect described control information and described upstream data.

Above-mentioned method, wherein, the phase difference of described first reference signal and described second reference signal is π.

Above-mentioned method, wherein,

$N_{\mathrm{cs}}^{\mathrm{RN}}=(N_{\mathrm{cs}}^{\mathrm{UE}}+M/2)\mathrm{mod}M$

Described

With

Be respectively the cyclic shift value of first reference signal and the second reference signal correspondence, described M is the sum of cyclic shift value.

Above-mentioned method, wherein, when described relay station sends upstream data based on described NACK signal on described first resource, the calculated signals channel response that the base station utilizes described first reference signal, second reference signal and receives, and utilize the result of calculation of described channel response to detect described control information and described upstream data is specially:

The base station utilizes described first reference signal to calculate first channel response, and utilize described second reference signal to calculate the second channel response, described first channel response is the channel response of the channel between base station and the user terminal, and described second channel response is the channel response of the channel between base station and the relay station;

The base station utilizes described first channel response to detect described control information, and utilizes described first channel response and second channel response to detect described upstream data.

Above-mentioned method, wherein, during upstream data when described relay station sends precoding based on described NACK signal on first resource after, the calculated signals channel response that the base station utilizes described first reference signal, second reference signal and receives, and utilize the result of calculation of described channel response to detect described control information and described upstream data is specially:

The base station utilizes described first reference signal to calculate first channel response, and utilize described second reference signal to calculate the second channel response, described first channel response is the channel response of the channel between base station and the user terminal, and described second channel response is the channel response of the channel between base station and the relay station;

The base station utilizes described first channel response to detect described control information, and the precoding mode of utilizing described first channel response, second channel response and relay station to adopt detects described upstream data.

Above-mentioned method, wherein, described precoding is space-frequency coding or phase place rotation.

Above-mentioned method, wherein, when described relay station based on the upstream data of described NACK signal after sending precoding on first resource, described precoding is the phase place rotation, phase rotation angle is

With

Difference; Described

With

Be respectively the cyclic shift value of first reference signal and the second reference signal correspondence, described M is the sum of cyclic shift value;

The calculated signals channel response that the base station utilizes described first reference signal, second reference signal and receives, and utilize the result of calculation of described channel response to detect described control information and described upstream data is specially:

The base station utilizes described first reference signal to calculate first channel response between a channel of equal value and base station and the user terminal;

The base station utilizes described first channel response to detect described control information, and utilizes described equivalent channels to detect described upstream data.

To achieve these goals, the embodiment of the invention also provides a kind of mobile communication system, comprises base station and relay station, and described base station comprises:

Sending module is used for sending the NACK signal to user terminal when the upstream data of the user terminal transmission that receives is incorrect;

First receiver module is used to receive upstream data, first reference signal that user terminal resends on first resource based on the NACK signal and the control information that is embedded into described upstream data;

Described relay station comprises:

Retransmit module is used for based on the upstream data of described NACK signal after sending upstream data or precoding on first resource, and second reference signal; Described second reference signal is different with described first reference signal;

Described base station also comprises:

Second receiver module is used to receive the upstream data after described relay station carries out precoding based on described NACK signal at the upstream data that sends on first resource or with described upstream data, and second reference signal;

Processing module is used to the calculated signals channel response that utilizes described first reference signal, second reference signal and receive, and utilizes the result of calculation of described channel response to detect described control information and described upstream data.

Above-mentioned mobile communication system, wherein, the phase difference of described first reference signal and described second reference signal is π.

Above-mentioned mobile communication system, wherein, when described relay station sent upstream data based on described NACK signal on first resource, described processing module specifically comprised:

The first channel response computing unit, be used to utilize described first reference signal to calculate first channel response, and utilize described second reference signal to calculate the second channel response, described first channel response is the channel response of the channel between base station and the user terminal, and described second channel response is the channel response of the channel between base station and the relay station;

First detecting unit is used to utilize described first channel response to detect described control information, and utilizes described first channel response and second channel response to detect described upstream data.

Above-mentioned mobile communication system, wherein, during upstream data when described relay station sends precoding based on described NACK signal on first resource after, described processing module specifically comprises:

The first channel response computing unit, be used to utilize described first reference signal to calculate first channel response, and utilize described second reference signal to calculate the second channel response, described first channel response is the channel response of the channel between base station and the user terminal, and described second channel response is the channel response of the channel between base station and the relay station;

Second detecting unit is used to utilize described first channel response to detect described control information, and the precoding mode of utilizing described first channel response, second channel response and relay station to adopt detects described upstream data.

Above-mentioned mobile communication system, wherein, described relay station is based on the upstream data of described NACK signal after sending precoding on first resource, and described precoding is the phase place rotation, and phase rotation angle is

With

Difference; Described

With

Be respectively the cyclic shift value of first reference signal and the second reference signal correspondence, described M is the sum of cyclic shift value;

Described processing module specifically comprises:

Second channel RESPONSE CALCULATION unit is used for calculating first channel response between a channel of equal value and base station and the user terminal according to described first reference signal;

The 3rd detecting unit is used to utilize described first channel response to detect described control information, and utilizes described equivalent channels to detect described upstream data.

The embodiment of the invention has following beneficial effect:

In the trunking method during uplink data retransmission of the embodiment of the invention, user terminal and relay station all carry out the transmission of upstream data and reference signal on same asset based on the NACK signal, because user terminal adopts different reference signals with relay station, so the base station can utilize reference signal to estimate channel response, detects control information and upstream data.

Because user terminal and relay station retransmit simultaneously, so can obtain the collaboration diversity gain.

In embodiments of the present invention, relay station carries out sending after the precoding to upstream data, so can obtain corresponding gain when the base station end detects.Further, when precoding is phase place rotation, and the anglec of rotation is With Difference the time, channel estimating can be carried out to the channel of stack, but not independent estimation H in the base station _MBAnd H _RBThe independent H of channel ratio of stack _MBAnd H _RBHave higher signal to noise ratio, therefore, can obtain better channel estimation accuracy.

Description of drawings

Fig. 1 is used for the schematic flow sheet of auxiliary uplink data retransmission for existing transparent relay;

Fig. 2 is used for the schematic flow sheet of auxiliary uplink data retransmission for a kind of transparent relay of the existing LTE of being used for system and LTE-A system;

Fig. 3 is used for the schematic flow sheet of auxiliary uplink data retransmission for the another kind of transparent relay of the existing LTE of being used for system and LTE-A system;

The schematic flow sheet of trunking method first embodiment when Fig. 4 is uplink data retransmission;

The schematic flow sheet of trunking method second embodiment when Fig. 5 is uplink data retransmission;

The schematic flow sheet of trunking method the 3rd embodiment when Fig. 6 is uplink data retransmission;

The schematic flow sheet of trunking method first embodiment when Fig. 7-Fig. 9 is the uplink data retransmission of third embodiment of the invention.

Embodiment

In the embodiment of the invention, when upstream data resends, user terminal sends the different reference signal of cyclic shift value with relay station on identical resource, make the base station to carry out input with the different reference signal that relay station sends based on user terminal.

Trunking method during the uplink data retransmission of the embodiment of the invention comprises:

First receiving step, upstream data, first reference signal that base station reception user terminal resends on first resource based on the NACK signal and the control information that is embedded into described upstream data;

Second receiving step, base station receive upstream data that relay station sends based on described NACK signal or described upstream data are carried out in the upstream data after the precoding one and second reference signal on first resource; Described second reference signal is different with described first reference signal;

The calculated signals channel response that channel response calculation procedure, base station are utilized described first reference signal, second reference signal and received;

Detect step, the base station utilizes the result of calculation of described channel response to detect described control information and described upstream data.

The present invention is described in detail with different implementations below.

Trunking method during the uplink data retransmission of first embodiment of the invention comprises as shown in Figure 4:

Step 41, base station receive first reference signal, upstream data that user terminal resends based on the NACK signal and the control information that is embedded into described upstream data on first resource;

Step 42, the base station receives second reference signal and the upstream data that relay station sends on first resource based on described NACK signal; Described second reference signal is different with described first reference signal;

Step 43, the base station utilizes described first reference signal and described second reference signal to calculate first channel response respectively and the second channel response (just utilizes described first reference signal to calculate first channel response, and utilize described second reference signal to calculate the second channel response), described first channel response is the channel response of the channel between base station and the user terminal, and described second channel response is the channel response of the channel between base station and the relay station;

Step 44, base station utilize described first channel response to detect described control information, and utilize described first channel response and second channel response to detect described upstream data.

Below above-mentioned process is elaborated.

User terminal is after the base station sends upstream data and control information A1, and the upstream data and the control information A1 of user terminal monitored and obtained to relay station;

The base station is detected the data of the user terminal that receives and is carried out normal ACK and NACK sends, if that is: correct, then feeding back ACK is given user terminal.If incorrect, then feed back NACK and give user terminal.

User terminal and relay station retransmit if desired according to ACK and NACK decision whether the carrying out re-transmission of data that the base station sends, and then user terminal carries out normal data re-transmission, that is: control signal A2 is embedded in the upstream data, and sends to the base station.

In LTE or LTE-A system, data channel and control channel all have the corresponding reference signal to be used to estimate channel response, thereby carry out the detection of data or control information.For the reference signal of data channel, employing produces for the mode that same basic sequence (Base Sequence) carries out cyclic shift, and promptly uplink reference signals can be identified by a cyclic shift parameter.Which cyclic shift parameter user terminal adopts, and passes through signaled by the base station.

In specific embodiments of the invention, user terminal adopts different reference signals with relay station, is described in detail as follows.

Because the cyclic shift parameter that user terminal adopted is notified by the base station, therefore relay station just can be known the reference signal that user terminal will adopt when the data re-transmission by the monitoring base station notice, thereby selects the another one reference signal according to the reference signal that user terminal will adopt when the data re-transmission.

In specific embodiments of the invention, relay station selects the criterion of reference signal and base station to be scheduled in advance, then the selected reference signal of relay station also can be determined according to the reference signal that user terminal will adopt when the data re-transmission in the base station, so this process does not need to define new signaling.

For the criterion of choosing of relay station selection reference signal, can set according to the performance requirement of system.For example,, can choose in the following manner so, make that the phase difference between the reference signal that user terminal and relay station select for use is π if the performance requirement of system is best channel estimating performance.

The cyclic shift value of supposing the user terminal reference signal is The cyclic shift value of relay station reference signal so

Can be calculated as follows:

$N_{\mathrm{cs}}^{\mathrm{RN}}=(N_{\mathrm{cs}}^{\mathrm{UE}}+6)\mathrm{<figure-callout\; id="12"\; label="mod"\; filenames="H2009102208982E0000011.png"\; state="\{\{state\}\}">mod</figure-callout>}12$

Certainly above-mentioned calculating is that the number with reference signal is 12 explanations of carrying out, and under the situation of other numbers, above-mentioned formula should be done respective change, and is as follows:

$N_{\mathrm{cs}}^{\mathrm{RN}}=(N_{\mathrm{cs}}^{\mathrm{UE}}+M/2)\mathrm{mod}M$

Wherein M is the number of cyclic shift value.

But in follow-up explanation, be 12 to describe still with the number of reference signal.

According to

With

Value, user terminal and relay station are selected following reference signal respectively for use:

$r_{u,v}^{{\mathrm{\&alpha;}}_{\mathrm{UE}}}\left(n\right)=e^{j{\mathrm{\&alpha;}}_{\mathrm{UE}}n}\&CenterDot;r_{u,v}\left(n\right),$ n＝1，2，......，N

$r_{u,v}^{{\mathrm{\&alpha;}}_{\mathrm{RN}}}\left(n\right)=e^{j{\mathrm{\&alpha;}}_{\mathrm{RN}}n}\&CenterDot;r_{u,v}\left(n\right),$ n＝1，2，......，N

Wherein: r _{U, v}(n) be basic reference signal sequence,

Length for reference signal sequence.

Should be understood that, in implementation procedure of the present invention, can realize best channel estimating performance, but With

Also can get any different value in the span.

According to above description, can know that reference signal, data and control information that user terminal sends are as follows respectively:

$r_{u,v}^{{\mathrm{\&alpha;}}_{\mathrm{UE}}}\left(n\right)=e^{j{\mathrm{\&alpha;}}_{\mathrm{UE}}n}\&CenterDot;r_{u,v}\left(n\right)$

d _UE(n)＝d(n)

S _UE(n)＝S(n)

And relay station does not send control information, and the reference signal that relay station sent, data are distinguished as follows:

$r_{u,v}^{{\mathrm{\&alpha;}}_{\mathrm{RN}}}\left(n\right)=e^{j{\mathrm{\&alpha;}}_{\mathrm{RN}}n}\&CenterDot;r_{u,v}\left(n\right)$

d _RN(n)＝d(n)

In these cases, the reference signal that receives of base station is:

$y_{\mathrm{RS}}=H_{\mathrm{MB}}{e}^{{\mathrm{j\&alpha;}}_{\mathrm{UE}}n}\&CenterDot;r_{u,v}\left(n\right)+H_{\mathrm{RB}}{e}^{j{\mathrm{\&alpha;}}_{\mathrm{RN}}n}\&CenterDot;r_{u,v}\left(n\right)+\mathrm{noise}$

Wherein: H _MBAnd H _RBRepresent the channel response of user terminal to base station and relay station channel response respectively to the base station.

And the data-signal that the base station receives is:

y _data＝H _MBd(n)+H _RBd(n)+noise

And the control information that the base station receives is:

y _control＝H _MBS(n)+noiSe

Because in specific embodiments of the invention, because

With

The value difference, so the reference signal that user terminal and relay station are selected for use respectively is also inequality, so the reference signal that the base station can utilize reference signal that user terminal selects for use and relay station to select for use is respectively come the channel response H between calculation base station and the user terminal _MBAnd the channel response H between base station and the relay station _RB

Obtaining H _MBAnd H _RBAfterwards, can utilize this H _MBAnd H _RBCalculate d (n) and s (n).

In the first embodiment of the present invention, because user terminal and relay station retransmit simultaneously, so can obtain the collaboration diversity gain, simultaneously, because relay station selects the criterion of reference signal and base station to be scheduled in advance, then the selected reference signal of relay station can be determined according to the reference signal that user terminal will adopt when the data re-transmission in the base station, so the retransmission processes of the embodiment of the invention does not need to define new signaling.

Trunking method during the uplink data retransmission of second embodiment of the invention comprises as shown in Figure 5:

Step 51, base station receive first reference signal, upstream data that user terminal resends based on the NACK signal and the control information that is embedded into described upstream data on first resource;

Step 52, base station receive relay station based on the upstream data of described NACK signal after second reference signal that sends on first resource and process precoding; Described second reference signal is different with described first reference signal;

Step 53, the base station utilizes described first reference signal and described second reference signal to calculate first channel response and second channel response respectively, described first channel response is the channel response of the channel between base station and the user terminal, and described second channel response is the channel response of the channel between base station and the relay station;

Step 54, base station utilize described first channel response to detect described control information, and the precoding mode of utilizing described first channel response, second channel response and relay station to adopt detects described upstream data.

Below above-mentioned process is elaborated.

In second specific embodiment of the present invention, user terminal is identical with the different reference signals and first embodiment that relay station adopts, is not described in detail at this.

In the second embodiment of the present invention, the reference signal that user terminal sent, data and control information are as follows respectively:

$r_{u,v}^{{\mathrm{\&alpha;}}_{\mathrm{UE}}}\left(n\right)=e^{j{\mathrm{\&alpha;}}_{\mathrm{UE}}n}\&CenterDot;r_{u,v}\left(n\right)$

d _UE(n)＝d(n)

S _UE(n)＝S(n)

And relay station does not send control information, and the reference signal that relay station sent, data are distinguished as follows:

$r_{u,v}^{{\mathrm{\&alpha;}}_{\mathrm{RN}}}\left(n\right)=e^{j{\mathrm{\&alpha;}}_{\mathrm{RN}}n}\&CenterDot;r_{u,v}\left(n\right)$

d _RN(n)＝F(d(n))

Wherein F (.) is the precoding function.

In these cases, the reference signal that receives of base station is:

$y_{\mathrm{RS}}=H_{\mathrm{MB}}{e}^{{\mathrm{j\&alpha;}}_{\mathrm{UE}}n}\&CenterDot;r_{u,v}\left(n\right)+H_{\mathrm{RB}}{e}^{j{\mathrm{\&alpha;}}_{\mathrm{RN}}n}\&CenterDot;r_{u,v}\left(n\right)+\mathrm{noise}$

Wherein: H _MBAnd H _RBRepresent the channel response of user terminal to base station and relay station channel response respectively to the base station.

And the data-signal that the base station receives is:

y _data＝H _MBd(n)+H _RBF(d(n))+noise

And the control information that the base station receives is:

y _control＝H _MBS(n)+noise

Because in specific embodiments of the invention, because

With

The value difference, so the reference signal that user terminal and relay station are selected for use respectively is also inequality, so the reference signal that the base station can utilize reference signal that user terminal selects for use and relay station to select for use is respectively come the channel response H between calculation base station and the user terminal _MBAnd the channel response H between base station and the relay station _RB

In the second embodiment of the present invention, relay station carries out precoding to upstream data, below a kind of possible precoding mode-space-frequency coding is described as follows:

Suppose that the data that user terminal sends are:

d(1)，d(2)，......，d(m)，d(m+1)......

The signal through space-frequency coding of relay station transmission is so:

-d ^*(2)，d ^*(1)，......，-d ^*(m+1)，d ^*(m)......

Obtaining H _MBAnd H _RBAfterwards, can utilize this H _MB, H _RBAnd the precoding mode that relay station adopts calculates d (n), and according to H _MBCalculate s (n).

In the second embodiment of the present invention, because user terminal and relay station retransmit simultaneously, so can obtain the collaboration diversity gain, simultaneously, because the criterion of relay station selection reference signal and precoding mode and base station are predetermined in advance, then the selected reference signal of relay station can be determined according to the reference signal that user terminal will adopt when the data re-transmission in the base station, so the retransmission processes of the embodiment of the invention does not need to define new signaling.

Simultaneously,, corresponding gain can be obtained, when being space-frequency coding, diversity gain can be obtained as the precoding mode because relay station has carried out precoding processing to upstream data, when the precoding mode is the phase place rotation, the delay diversity that can obtain to circulate gain.

In second embodiment of the invention, if when adopting phase place rotation precoding mode, the delay diversity that can obtain to circulate gain, but for phase place rotation precoding mode, the control phase anglec of rotation then can obtain better channel estimation accuracy, is described in detail as follows.

Trunking method during the uplink data retransmission of third embodiment of the invention comprises as shown in Figure 6:

Step 61, base station receive first reference signal, upstream data that user terminal resends based on the NACK signal and the control information that is embedded into described upstream data on first resource;

Step 62, base station receive second reference signal and the postrotational upstream data of process phase place that relay station sends on first resource based on described NACK signal; Described second reference signal is different with described first reference signal; The angle of described phase place rotation is

With

Difference; Described With

Be respectively the cyclic shift value of first reference signal and the second reference signal correspondence, described M is the sum of cyclic shift value;

Step 63, reference signal that the base station basis receives and described first reference signal are calculated first channel response between a channel of equal value and base station and the user terminal;

Step 64, base station utilize described first channel response to detect described control information, and utilize described equivalent channels to detect described upstream data.

Below above-mentioned process is elaborated.

In the 3rd specific embodiment of the present invention, user terminal is identical with the different reference signals and first embodiment that relay station adopts, is not described in detail at this.

In the second embodiment of the present invention, in the precoding mode is that space-frequency coding has been described in detail, it can obtain optimum performance, but the power peak-to-average force ratio in the time of can increasing the relay station transfer of data, in order to keep the power peak-to-average force ratio, in the third embodiment of the present invention, the reference signal that user terminal sent, data and control information are as follows respectively:

$r_{u,v}^{{\mathrm{\&alpha;}}_{\mathrm{UE}}}\left(n\right)=e^{j{\mathrm{\&alpha;}}_{\mathrm{UE}}n}\&CenterDot;r_{u,v}\left(n\right)$

d _UE(n)＝d(n)

s _UE(n)＝s(n)

$s_{\mathrm{UE}}\left(n\right)=s\left(n\right)$

And relay station does not send control information, and the reference signal that relay station sent, data are distinguished as follows:

$r_{u,v}^{{\mathrm{\&alpha;}}_{\mathrm{RN}}}\left(n\right)=e^{j{\mathrm{\&alpha;}}_{\mathrm{RN}}n}\&CenterDot;r_{u,v}\left(n\right)$

$d_{\mathrm{RN}}\left(n\right)=e^{j({\mathrm{\&alpha;}}_{\mathrm{RN}}-{\mathrm{\&alpha;}}_{\mathrm{UE}})n}\&CenterDot;d\left(n\right)$

That is to say that the precoding described in the step 62 is the phase place rotation of the data symbol in the upstream data having been carried out frequency domain, the power peak-to-average force ratio when this precoding mode can not change transfer of data, also can not reduce the power efficiency of relay station power amplifier.

In these cases, the reference signal that receives of base station is:

$y_{\mathrm{RS}}=H_{\mathrm{MB}}{e}^{{\mathrm{j\&alpha;}}_{\mathrm{UE}}n}\&CenterDot;r_{u,v}\left(n\right)+H_{\mathrm{RB}}{e}^{j{\mathrm{\&alpha;}}_{\mathrm{RN}}n}\&CenterDot;r_{u,v}\left(n\right)+\mathrm{noise}$

$={(H_{\mathrm{MB}}+H_{\mathrm{RB}}{e}^{j({\mathrm{\&alpha;}}_{\mathrm{RN}}-{\mathrm{\&alpha;}}_{\mathrm{UE}})n})\&CenterDot;e}^{{\mathrm{j\&alpha;}}_{\mathrm{UE}}n}\&CenterDot;r_{u,v}\left(n\right)+\mathrm{noise}$

Wherein: H _MBAnd H _RBRepresent the channel response of user terminal to base station and relay station channel response respectively to the base station.

First reference signal that reference signal that receives based on the base station and user terminal resend on first resource based on the NACK signal

Can calculate following equivalent channels

Certainly simultaneously can also calculate H _MB

And the data-signal that the base station receives is:

$y_{\mathrm{data}}=H_{\mathrm{MB}}d\left(n\right)+H_{\mathrm{RB}}{e}^{j({\mathrm{\&alpha;}}_{\mathrm{RN}}-{\mathrm{\&alpha;}}_{\mathrm{UE}})n}\&CenterDot;d\left(n\right)+\mathrm{noise}$

$=(H_{\mathrm{MB}}+H_{\mathrm{RB}}{e}^{j({\mathrm{\&alpha;}}_{\mathrm{RN}}-{\mathrm{\&alpha;}}_{\mathrm{UE}})n})\&CenterDot;d\left(n\right)+\mathrm{noise}$

So based on the above equivalent channels that calculates

Can directly detect and obtain upstream data d (n).

And the control information that the base station receives is:

y _control＝H _MBs(n)+noise

Based on the above H that calculates _MBCan detect controlled information s (n).

In the first embodiment of the present invention, because user terminal and relay station retransmit simultaneously, so can obtain the collaboration diversity gain, simultaneously, because the criterion of relay station selection reference signal and precoding mode and base station are predetermined in advance, then the selected reference signal of relay station can be determined according to the reference signal that user terminal will adopt when the data re-transmission in the base station, so the retransmission processes of the embodiment of the invention does not need to define new signaling.

Simultaneously, because relay station has carried out precoding processing to upstream data, can obtain the gain of circulation delay diversity.

Simultaneously, because precoding is the phase place rotation of the data symbol in the upstream data having been carried out frequency domain, the power peak-to-average force ratio when this precoding mode can not change transfer of data, also can not reduce the power efficiency of relay station power amplifier.

By precoding, channel estimating can be carried out to the channel of stack in the base station, but not independent estimation H _MBAnd H _RBThe independent H of channel ratio of stack _MBAnd H _RBHave higher signal to noise ratio, therefore, can obtain better channel estimation accuracy.

The mobile communication system of the embodiment of the invention comprises base station and relay station, and described base station comprises:

Sending module is used for sending the NACK signal to user terminal when the upstream data of the user terminal transmission that receives is incorrect;

First receiver module is used to receive upstream data, first reference signal that user terminal resends on first resource based on the NACK signal and the control information that is embedded into described upstream data;

Described relay station comprises:

Retransmit module is used for based on the upstream data of described NACK signal after sending upstream data or precoding on first resource, and second reference signal; Described second reference signal is different with described first reference signal;

Described base station also comprises:

Second receiver module, be used to receive described relay station based on described NACK signal at upstream data that sends on first resource or the upstream data after the precoding, and second reference signal;

Processing module is used to the calculated signals channel response that utilizes described first reference signal, second reference signal and receive, and utilizes the result of calculation of described channel response to detect described control information and described upstream data.

The phase difference of described first reference signal and described second reference signal is π.

When described relay station sent upstream data based on described NACK signal on first resource, described processing module specifically comprised:

The first channel response computing unit, utilize described first reference signal and described second reference signal to calculate first channel response and second channel response respectively, described first channel response is the channel response of the channel between base station and the user terminal, and described second channel response is the channel response of the channel between base station and the relay station;

First detecting unit, base station utilize described first channel response to detect described control information, and utilize described first channel response and second channel response to detect described upstream data.

During upstream data when described relay station sends precoding based on described NACK signal on first resource after, described processing module specifically comprises:

The first channel response computing unit, utilize described first reference signal and described second reference signal to calculate first channel response and second channel response respectively, described first channel response is the channel response of the channel between base station and the user terminal, and described second channel response is the channel response of the channel between base station and the relay station;

Second detecting unit is used to utilize described first channel response to detect described control information, and the precoding mode of utilizing described first channel response, second channel response and relay station to adopt detects described upstream data.

Described relay station is based on the upstream data of described NACK signal after sending precoding on first resource, and described precoding is the phase place rotation, and phase rotation angle is With

Difference; Described

With

Be respectively the cyclic shift value of first reference signal and the second reference signal correspondence, described M is the sum of cyclic shift value;

Described processing module specifically comprises:

Second channel RESPONSE CALCULATION unit is used for calculating first channel response between a channel of equal value and base station and the user terminal according to described first reference signal;

The 3rd detecting unit is used to utilize described first channel response to detect described control information, and utilizes described equivalent channels to detect described upstream data.

Effect to the embodiment of the invention compares with the mode and the prior art of tabulating below.

As can be seen from Table 1, compare data transmission performance that embodiment of the invention method can obtain and control information transmission performance and do not need to increase new signaling with existing scheme.Suggest plans in addition and also solved all the other problems that exist in other scheme, as the problem of " the expendable mistake that the retransmits " problem in the always PHICH ACK scheme and " the correct receive time delay of larger data " in Fujitsu's scheme.

The validity of suggesting plans in order to verify has been carried out emulation and has been compared with existing scheme the 3rd embodiment of the scheme that proposed.

Emulation is provided with as follows:

Channel model: TU6 channel, piece decline (block fading)

Number of resource blocks (Resource Block): data: 3 and 10, control information: 1.

Modulation system: data: 16QAM; Control information: QPSK.

Chnnel coding: 1/2 code check; Data: turbo coding; Control information: convolutional encoding.

Relay station reference signal cyclic shift value choose criterion:

Channel estimation method: data: least mean-square error; Control information: DCIR2+windowing.

Doppler frequency shift: 10 hertz.

Fig. 7 has provided when adopting 3 Resource Block, the performance of transfer of data.The method of the 3rd embodiment (suggest plans) can be obtained optimum performance as can be seen.Compare with " Fujitsu " scheme with " always PHICH ACK " scheme, institute suggests plans and can obtain collaboration diversity gain and the gain of circulation delay diversity; Compare with " relay station is punchinged " scheme, institute suggests plans and can obtain to circulate the delay diversity gain.

Fig. 8 has provided when adopting 10 Resource Block, the performance of transfer of data, similar conclusion when it can obtain with 3 Resource Block transfer of data.This shows that suggest plans all has preferable performance for different resource block size.

Fig. 9 has provided when adopting 1 Resource Block, the control information transmission performances.Because control information is transmitted in control channel in " always PHICHACK " scheme, adopt different transmission meanss, for example to carry out spread processing to symbol, and " relay station punchinges " scheme, institute suggest plans and " Fujitsu " scheme in control information be embedded in and transmit in the data channel, there are not processing such as spread spectrum, so do not provide the performance of " always PHICH ACK " scheme among Fig. 9." relay station is punchinged " scheme is owing to utilize unmatched channel estimating to carry out the detection of control information as can be seen from Figure 9, and to such an extent as to the non-constant of its performance is cisco unity malfunction.The method of the 3rd embodiment (institute suggests plans) and " Fujitsu's scheme " all can obtain preferable performance.

The above only is a preferred implementation of the present invention; should be pointed out that for those skilled in the art, under the prerequisite that does not break away from the principle of the invention; can also make some improvements and modifications, these improvements and modifications also should be considered as protection scope of the present invention.

Claims (12)

1. the trunking method a during uplink data retransmission is characterized in that, comprising:

Upstream data, first reference signal that base station reception user terminal resends on first resource based on the NACK signal and the control information that is embedded into described upstream data;

The base station receives the upstream data after relay station carries out precoding based on described NACK signal at the upstream data that sends on described first resource or with described upstream data, and second reference signal; Described second reference signal is different with described first reference signal;

The calculated signals channel response that the base station utilizes described first reference signal, second reference signal and receives, and utilize the result of calculation of described channel response to detect described control information and described upstream data.

2. method according to claim 1 is characterized in that, the phase difference of described first reference signal and described second reference signal is π.

3. method according to claim 2 is characterized in that:

$N_{\mathrm{cs}}^{\mathrm{RN}}=(N_{\mathrm{cs}}^{\mathrm{UE}}+M/2)\mathrm{mod}M$

Described

With Be respectively the cyclic shift value of first reference signal and the second reference signal correspondence, described M is the sum of cyclic shift value.

4. according to claim 1,2 or 3 described methods, it is characterized in that, when described relay station sends upstream data based on described NACK signal on described first resource, the calculated signals channel response that the base station utilizes described first reference signal, second reference signal and receives, and utilize the result of calculation of described channel response to detect described control information and described upstream data is specially:

The base station utilizes described first reference signal to calculate first channel response, and utilize described second reference signal to calculate the second channel response, described first channel response is the channel response of the channel between base station and the user terminal, and described second channel response is the channel response of the channel between base station and the relay station;

The base station utilizes described first channel response to detect described control information, and utilizes described first channel response and second channel response to detect described upstream data.

5. according to claim 1,2 or 3 described methods, it is characterized in that, during upstream data when described relay station sends described precoding based on described NACK signal on described first resource after, the calculated signals channel response that the base station utilizes described first reference signal, second reference signal and receives, and utilize the result of calculation of described channel response to detect described control information and described upstream data is specially:

The base station utilizes described first reference signal to calculate first channel response, and utilize described second reference signal to calculate the second channel response, described first channel response is the channel response of the channel between base station and the user terminal, and described second channel response is the channel response of the channel between base station and the relay station;

The base station utilizes described first channel response to detect described control information, and the precoding mode of utilizing described first channel response, second channel response and relay station to adopt detects described upstream data.

6. method according to claim 5 is characterized in that, described precoding is space-frequency coding or phase place rotation.

7. according to claim 1,2 or 3 described methods, it is characterized in that, when described relay station based on the upstream data of described NACK signal after sending precoding on first resource, described precoding is the phase place rotation, phase rotation angle is

With

Difference; Described

With

Be respectively the cyclic shift value of first reference signal and the second reference signal correspondence, described M is the sum of cyclic shift value;

The calculated signals channel response that the base station utilizes described first reference signal, second reference signal and receives, and utilize the result of calculation of described channel response to detect described control information and described upstream data is specially:

The base station utilizes described first reference signal to calculate first channel response between a channel of equal value and base station and the user terminal;

The base station utilizes described first channel response to detect described control information, and utilizes described equivalent channels to detect described upstream data.

8. a mobile communication system comprises base station and relay station, it is characterized in that, described base station comprises:

Sending module is used for sending the NACK signal to user terminal when the upstream data of the user terminal transmission that receives is incorrect;

First receiver module is used to receive upstream data, first reference signal that user terminal resends on first resource based on the NACK signal and the control information that is embedded into described upstream data;

Described relay station comprises:

Retransmit module is used for based on the upstream data of described NACK signal after sending upstream data or precoding on first resource, and second reference signal; Described second reference signal is different with described first reference signal;

Described base station also comprises:

Second receiver module is used to receive the upstream data after described relay station carries out precoding based on described NACK signal at the upstream data that sends on first resource or with described upstream data, and second reference signal;

Processing module is used to the calculated signals channel response that utilizes described first reference signal, second reference signal and receive, and utilizes the result of calculation of described channel response to detect described control information and described upstream data.

9. mobile communication system according to claim 8 is characterized in that, the phase difference of described first reference signal and described second reference signal is π.

10. according to Claim 8 or 9 described mobile communication system, it is characterized in that when described relay station sent upstream data based on described NACK signal on first resource, described processing module specifically comprised:

The first channel response computing unit, be used to utilize described first reference signal to calculate first channel response, and utilize described second reference signal to calculate the second channel response, described first channel response is the channel response of the channel between base station and the user terminal, and described second channel response is the channel response of the channel between base station and the relay station;

First detecting unit is used to utilize described first channel response to detect described control information, and utilizes described first channel response and second channel response to detect described upstream data.

11. according to Claim 8 or 9 described mobile communication system, it is characterized in that during upstream data when described relay station sends precoding based on described NACK signal on first resource after, described processing module specifically comprises:

The first channel response computing unit, be used to utilize described first reference signal to calculate first channel response, and utilize described second reference signal to calculate the second channel response, described first channel response is the channel response of the channel between base station and the user terminal, and described second channel response is the channel response of the channel between base station and the relay station;

Second detecting unit is used to utilize described first channel response to detect described control information, and the precoding mode of utilizing described first channel response, second channel response and relay station to adopt detects described upstream data.

12. according to Claim 8 or 9 described mobile communication system, it is characterized in that described relay station is based on the upstream data of described NACK signal after sending precoding on first resource, described precoding is the phase place rotation, and phase rotation angle is

With

Difference; Described

With

Be respectively the cyclic shift value of first reference signal and the second reference signal correspondence, described M is the sum of cyclic shift value;

Described processing module specifically comprises:

Second channel RESPONSE CALCULATION unit is used for calculating first channel response between a channel of equal value and base station and the user terminal according to described first reference signal;

The 3rd detecting unit is used to utilize described first channel response to detect described control information, and utilizes described equivalent channels to detect described upstream data.

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