CN101656982B - Transmit diversity method of cooperation multipoint distribution - Google Patents

Abstract

The invention provides a transmit diversity method of cooperation multipoint distribution, comprising the following steps: all base stations of cooperation multipoint distribution transmit identical data edition to EU, all the base stations transmit data on different subcarrier resources, and an SFBC transmit mode is adopted in the base stations; or all the base stations of cooperation multipoint distribution transmit different data editions to EU, and all the base stations transmit data on different subcarrier resources, and the SFBC transmit mode is adopted in the base stations. In the way, diversity gain is obtained by the SFBC transmission on one hand, on the other hand, a plurality of the base stations transmit identical or different data edition with same code words and bitwise combination is further carried out at the receiving end, thereby obtaining the gain and improving the transmission performance of the system.

Description

A kind of transmission deversity scheme of cooperative multipoint transmission

Technical field

The present invention relates to cooperative multipoint transmission (CoMP) technology, particularly a kind of transmission deversity scheme of cooperative multipoint transmission.

Background technology

LTE-Advanced proposes to pass through cooperative multipoint transmission, and (Cordinated Multi-Pointtransmission/reception CoMP) improves the throughput of the cell coverage area and the Cell Edge User of High Data Rate, and then improves throughput of system.The CoMP technology means to be needed between a plurality of cell base stations (suppose sub-district of a base stations control, a base station is as a point in the cooperative multipoint transmission) that are on the diverse geographic location dynamically to coordinate to send data.The CoMP technology mainly contains following two types:

Cooperative scheduling/cooperative beam excipient technology:, have a plurality of points to participate in cooperative scheduling to a UE; The result of scheduling controls the interference that comes from other points on a moment or the band resource, having only a point that UE is sent data.

Combined Treatment/transmission technology: to a UE, cooperate between a plurality of points, send data simultaneously.

To Combined Treatment/transmission technology, the major programme that present stage proposed has: the spatial reuse transmission plan (coherent transfer) that carries out the associating precoding between each point; Carry out the spatial reuse transmission plan (incoherent transmission) of precoding on each aspect separately; The transmission diversity scheme of multipoint cooperative.

In the LTE system, space multiplexing mode converts the transmission diversity mode into when channel transmission quality is very poor, therefore sends the retreatment scheme that diversity mode is a space multiplexing mode.Equally, the transmission diversity scheme of multipoint cooperative can be used as the retreatment scheme of the spatial multiplex scheme of multipoint cooperative, so the diversity scheme of coordinate multipoint is understood more robust on performance.

Sending diversity mode in the LTE system at present is space frequency block coding (SFBC), and concrete implementation is following:

Suppose that transmitting terminal has 2 transmitting antennas, be expressed as antenna 0 and antenna 1 respectively.Antenna 0 occupies identical frequency resource with antenna 1.A data sequence { S ₀, S ₁, S ₂, S ₃... Through the SFBC encoder, the transmission sequence on antenna 0 is { S ₀, S ₁, S ₂, S ₃..., the element in the sequence is mapped to subcarrier f respectively ₀, f ₁, f ₂, f ₃On; Transmission sequence on antenna 1 is { S ₁ ^*, S ₀ ^*,-S ₃ ^*, S ₂ ^*..., be mapped to subcarrier f respectively ₀, f ₁, f ₂, f ₃On.Therefore to two adjacent data symbol S in the data sequence _2i, S _2i+1, at subcarrier f _2iOn, antenna 0 sends S respectively with antenna 1 _2iWith-S _2i+1 ^*, with f _2iAdjacent subcarrier f _2i+1On, antenna 0 sends S respectively with antenna 1 _2i+1And S _2i ^*The visible Fig. 1 of the Launching Model of SFBC.

In the LTE-Advanced system, the diversity scheme of a kind of coordinate multipoint that is proposed is: unite on each aspect of cooperation and carry out beam shaping, realized sending a minute collection between a plurality of points as a transmission mouthful (virtual transmit antennas) at one o'clock.But the beam shaping technology must competence exertion effect under the correlated channels environment; That is to say; Under the condition that only channel of many antennas is relevant in a point at present, could use this diversity scheme, obtain diversity gain; And the UE receiving terminal has only symbol level to merge, and the diversity gain that is provided is limited.

Summary of the invention

In view of this, the present invention provides a kind of transmission deversity scheme of cooperative multipoint transmission, for relevant or uncorrelated channel circumstance, the branch collection of system can be provided all.

For realizing above-mentioned purpose, the present invention adopts following technical scheme:

A kind of transmission deversity scheme of cooperative multipoint transmission comprises:

Participation is to each base station of the cooperative multipoint transmission of UE, and to the same versions of data of said UE transmission data to be transferred, and space frequency block coding SFBC is carried out to said data to be transferred in said each base station on different subcarrier resources.

Preferably; In advance under the number of base stations of different participations to the cooperative multipoint transmission of said UE; The SFBC that carry out said data to be transferred on different subcarrier resources said each base station of emulation; Confirm corresponding different base stations number, the signal to noise ratio of system and the mapping relations between the error rate;

Signal to noise ratio according to current channel circumstance requires and target error rate, selects corresponding number of base stations, confirms to participate in each base station to the cooperative multipoint transmission of said UE.

Preferably; This method further comprises: the data symbol sequence that said UE sends said each base station receives respectively and detects; And the symbol detection sequence of each base station is carried out demodulation respectively obtain soft bit sequence; The soft bit sequence of each base station that obtains is carried out the bit merging, be combined the result again and decipher.

A kind of transmission deversity scheme of cooperative multipoint transmission comprises:

Participation is to each base station of the cooperative multipoint transmission of UE, and to the different pieces of information version of said UE transmission data to be transferred, and space frequency block coding SFBC is carried out to said data to be transferred in said each base station on different subcarrier resources.

Preferably; In advance under the number of base stations of different participations to the cooperative multipoint transmission of said UE; The SFBC that carry out said data to be transferred on identical sub-carrier resources said each base station of emulation confirms corresponding different base stations number, the signal to noise ratio of system and the mapping relations between the error rate;

Signal to noise ratio according to current channel circumstance requires and target error rate, selects corresponding number of base stations, confirms to participate in each base station to the cooperative multipoint transmission of said UE.

Preferably, utilize control information to issue the versions of data of sending said each base station number to said UE.

Preferably; This method further comprises: the data symbol sequence that said UE sends said each base station receives respectively and detects; Confirm the symbol detection sequence of said each base station, and the symbol detection sequence of each base station is carried out demodulation respectively obtain soft bit sequence, the versions of data of sending according to each base station number; The soft bit sequence of each base station that obtains is carried out the bit merging, be combined the result again and decipher.

A kind of transmission deversity scheme of cooperative multipoint transmission comprises:

The high-rise versions of data of confirming that each base station is sent to UE of system, and notify said UE the versions of data that send each base station, said each base station is for participating in each base station to the cooperative multipoint transmission of UE;

If the versions of data that send said each base station is identical; Confirm that then sending mode is case1; The same versions of data that data to be transferred is sent to said UE in said each base station, and space frequency block coding SFBC is carried out to said data to be transferred in said each base station on different subcarrier resources;

If the versions of data that send said each base station is different; Confirm that then sending mode is case2; Said each base station is to the different pieces of information version of said UE transmission data to be transferred, and space frequency block coding SFBC is carried out to said data to be transferred in said each base station on different subcarrier resources.

Preferably, said system high level is confirmed the versions of data that send said each base station according to the occupation condition and the disposal ability of current said each base station.

Visible by technique scheme, among the present invention, provide two kinds and send diversity mode; Under a kind of pattern, participate in each base station of cooperative multipoint transmission, send identical versions of data to UE; Identical data is sent in each base station on different subcarrier resources, adopt the SFBC send mode in the base station, like this; Obtain diversity gain by SFBC on the one hand, identical data are sent in a plurality of on the other hand base stations, can realize that at receiving terminal UE the symbol level that sends data merges and bit level merging; Under the another kind of pattern, participate in each base station of cooperative multipoint transmission, send different versions of data to UE; Identical data is sent in each base station on different subcarrier resources; Adopt the SFBC send mode in the base station, like this, obtain diversity gain by SFBC on the one hand; The different editions of data to be transferred is sent in a plurality of on the other hand base stations, can realize sending the symbol level and the bit level merging of data at receiving terminal UE.To sum up, above-mentioned two kinds are sent diversity mode, all can obtain diversity gain, and still can improve the transmission performance of system under the relevant channel circumstance.

Description of drawings

Fig. 1 is the SFBC transmission pattern in the LTE system.

Fig. 2 is a concrete transmission diversity mode sketch map of the present invention.

Fig. 3 is the following two kinds of simulation result comparison diagrams that send diversity mode of case1 and case2.

Fig. 4 is the receive mode sketch map of receiving terminal.

Embodiment

For making the object of the invention, technological means and advantage clearer, the present invention is explained further details below in conjunction with accompanying drawing.

In the LTE system, space multiplexing mode converts the transmission diversity mode into when channel transmission quality is very poor, therefore sends the retreatment scheme that diversity mode is a space multiplexing mode.Specifically the transmission in the LTE system divides collection to be space frequency block coding (SFBC).For realizing the compatibility of LTE-Advanced to LTE, the transmission of cooperative multipoint transmission divides collection also to carry out based on SFBC among the application LTE-Advanced.And when being applied to SFBC in the cooperative multipoint transmission,, on each point many transmit antennas are arranged all for the each point (being each base station) of participating in cooperation transmission, therefore need many antennas of comprehensive each point to consider how to realize SFBC.

Particularly, be to realize the compatibility of LTE-Advanced to LTE, the sending mode that keeps as far as possible stipulating among SFBC mode and the LTE on each base station is consistent; On this basis; The versions of data of sending on the every antenna of each point of needs consideration; And the sub-carrier resources that adopts on each antenna of each point during space frequency block coding, thereby guarantee can not produce the phase mutual interference between each base station on the one hand, can improve system's receptivity on the other hand.

Based on above-mentioned consideration, the transmission that the present invention provides two kinds of patterns in the cooperative multipoint transmission divides the collection implementation, is respectively case1 and case2.

Send in the branch collection implementation at two kinds, on a plurality of points of participating in cooperation transmission, a base station is as dominant base, and other base stations are as cooperative base station.Carry out data interaction through X2 interface between dominant base and the cooperative base station, realize communication fully.Dominant base and cooperative base station are sent same code word, and cooperative base station can be sent the versions of data identical with dominant base, also can send different versions of data separately.Wherein, for certain UE, participation can be confirmed through existing mode each base station of the cooperative multipoint transmission of this UE, and transmission diversity mode of the present invention is on the basis of each base station of having confirmed the participation cooperative multipoint transmission, to carry out.

Particularly; In case1, participate in each base station to the cooperative multipoint transmission of certain UE, send the identical data version of same code word to this UE; And each base station is carried out SFBC and is sent on the different subcarriers resource; Wherein, the SFBC sending mode of each base station is identical with SFBC sending mode among the LTE, and the number of transmit antennas of each base station can be 2,4,8 etc.Adopt under this transmission diversity mode; The sub-carrier resources that SFBC is carried out in each base station is different, thereby makes the transmission data of each base station separate, can not produce interference; The data that receiving terminal sends the base station are carried out symbol detection respectively and are merged; Obtain to send diversity gain, the softer bit sequence of the demodulation of a plurality of base stations is carried out bit level merging, further improve system's receptivity.

In case2; Participation is to each base station of the cooperative multipoint transmission of certain UE; Send the different pieces of information version of same code word to this UE, and each base station carries out SFBC and sends on different subcarrier resources, wherein; The SFBC sending mode of each base station still with LTE in the SFBC sending mode identical, the number of transmit antennas of each base station can be 2,4,8 etc.The SFBC transmission is carried out in each base station on different subcarrier resources on the one hand, can avoid the phase mutual interference between each base station, and the different pieces of information version of same code word is sent in each base station on the other hand, and receiving terminal can be realized bit level merging.Particularly, the data that receiving terminal sends the base station are carried out symbol detection respectively and are merged, and obtain to send diversity gain, send the version of data afterwards according to each base station, the soft bit of the demodulation of each base station is carried out bit merge, and further improve system's receptivity.

Next, carrying out cooperative multipoint transmission with two base stations is example, carries out the specific descriptions of the transmission diversity mode of two kinds of patterns.Wherein, suppose that each base station all adopts 2 antenna transmission data, object UE adopts an antenna to receive.Certainly, in practical application, be not limited only to the situation of 2 transmit antennas, for other number of transmit antennas such as 4,8, the present invention is suitable equally.

Transmission diversity mode concrete under two kinds of patterns of the present invention is as shown in Figure 2.Wherein, S ₀, S ₁Expression is 1 signal that sends from the base station; T ₀, T ₁Expression is 2 signals that send from the base station.() ^*Expression is to the conjugate transpose of ().

Under Case1, the transmission versions of data of two base stations is identical, i.e. S ₀=T ₀, S ₁=T ₁Under case2, different pieces of information version, i.e. S are sent with base station 2 in base station 1 ₀≠ T ₀, S ₁≠ T ₁

Under two kinds of patterns, the subcarrier resource distribution that is used to carry data symbol is adopted in a like fashion.Particularly, for two base stations, adopt different subcarrier resources to carry the transmission signal of base station separately.The subcarrier allocation of two base station carrying data symbols is specifically as shown in Figure 2, establishes i=0, and 1 ..., on subcarrier 4i and 4i+1, two antennas of base station 1 carry out the send mode of SFBC; On subcarrier 4i+2 and 4i+3, two antennas of base station 2 carry out the SFBC send mode.The transmission of base station 1 and base station 2 is carried out simultaneously.Wherein, in the SFBC encoder of base station 1 and base station 2, identical in the SFBC mode of respectively the data symbol being carried out separately and the LTE system.

For any one sending mode, two base stations are identical for the SFBC mode of adjacent-symbol, and difference only is to carry the subcarrier difference of data symbol.Be the mode of SFBC under two kinds of patterns of example explanation the present invention below with base station 1.

For the SFBC encoder of base station 1, at the adjacent two data symbol S of coding input ₀And S ₁The time, utilize adjacent subcarrier 0 and subcarrier 1 to carry two data symbols.Particularly, with first data symbol S in these two data symbols ₀Be modulated on the subcarrier 0, with second data symbol S in these two data symbols ₁Be modulated on the subcarrier 1, and be positioned at the data symbol S on the subcarrier 0 after will modulating ₀With the data symbol S that is positioned on the subcarrier 1 ₁ Antenna 1 through base station 1 sends; Simultaneously, with the conjugation opposite number-S of second data symbol in these two data symbols ₁ ^*Be modulated on the subcarrier 0, with the conjugate of symbol S of first data symbol in these two data symbols ₀ ^*Be modulated on the subcarrier 1, and being positioned on the subcarrier 0 after will modulating-S ₁ ^*With the S that is positioned on the subcarrier 1 ₀ ^* Antenna 2 through base station 1 sends.By above-mentioned visible, identical in the cataloged procedure of two adjacent data symbols and the LTE system in the SFBC of base station 1 encoder.

As previously mentioned; It is different that base station 1 and base station 2 are used to carry the subcarrier of data symbol, this be because, for the transmission data of each base station do not constitute the phase mutual interference at the UE receiving terminal; Need between each base station, carry out Hong Fenji, so different base stations utilizes different subcarriers to carry data symbol.

By the way after object UE is sent data symbol, when i=0, the receiving symbol y of receiving terminal on subcarrier 0 ₀For

${\mathrm{<figure-callout\; id="0"\; label="y"\; filenames="H2009100927539E00021.png"\; state="\{\{state\}\}">y</figure-callout>}}_0=h_{00}{S}_0+h_{01}(-S_1^{*})+N_0---\left(1\right)$

The reception signal y of receiving terminal on subcarrier 1 ₁For

${\mathrm{<figure-callout\; id="1"\; label="y"\; filenames="H2009100927539E00011.png,H2009100927539E00022.png"\; state="\{\{state\}\}">y</figure-callout>}}_1=h_{10}{S}_1+h_{11}\left(S_0^{*}\right)+N_1---\left(2\right)$

The reception signal y of receiving terminal on subcarrier 2 ₂For

${\mathrm{<figure-callout\; id="2"\; label="y"\; filenames="H2009100927539E00011.png,H2009100927539E00021.png"\; state="\{\{state\}\}">y</figure-callout>}}_2=H_{20}{T}_0+H_{21}\left({-T}_1^{*}\right)+N_2---\left(3\right)$

The reception signal y of receiving terminal on subcarrier 3 ₃For

${\mathrm{<figure-callout\; id="3"\; label="y"\; filenames="H2009100927539E00011.png,H2009100927539E00012.png"\; state="\{\{state\}\}">y</figure-callout>}}_3=H_{30}{\mathrm{<figure-callout\; id="1"\; label="T"\; filenames="H2009100927539E00011.png,H2009100927539E00022.png"\; state="\{\{state\}\}">T</figure-callout>}}_1+H_{31}\left(T_0^{*}\right)+N_3---\left(4\right)$

Wherein, h _IjExpression is from the domain channel response the base station 1 to UE, and i representes the subcarrier sequence number, and j representes the transmitting antenna sequence number.H _IjDomain channel response between the expression base station 2 to UE, i representes the subcarrier sequence number, j representes the transmitting antenna sequence number.N ₀, N ₁Expression AWGN noise.According to (1)-(4), can be with the receiving symbol y on the subcarrier 0,1,2,3 ₀, y ₁, y ₂, y ₃Be written as following form

$\left[\begin{array}{c}{y}_0\\ {-y}_1^{*}\\ y_2\\ {-y}_3^{*}\end{array}\right]=\left[\begin{array}{cccc}{h}_{00}& h_{01}& 0& 0\\ {-h}_{01}^{*}& h_{00}^{*}& 0& 0\\ 0& 0& H_{20}& H_{21}\\ 0& 0& {-H}_{31}^{*}& H_{30}^{*}\end{array}\right]\left[\begin{array}{c}{S}_0\\ {-S}_1^{*}\\ T_0\\ {-T}_1^{*}\end{array}\right]+\left[\begin{array}{c}{N}_0\\ N_1\\ N_2\\ N_3\end{array}\right]---\left(5\right)$

Because the domain channel response of two adjacent number of sub-carrier 0,1 remains unchanged basically, the domain channel response of two adjacent number of sub-carrier 2,3 also remains unchanged basically, and therefore h is arranged ₀₁≈ h ₁₁, H ₂₁≈ H ₃₁, h ₀₀≈ h ₁₀, H ₂₀≈ H ₃₀, formula (5) can be write as following matrix form

$\left[\begin{array}{c}{y}_0\\ {-\mathrm{<figure-callout\; id="1"\; label="y"\; filenames="H2009100927539E00011.png,H2009100927539E00022.png"\; state="\{\{state\}\}">y</figure-callout>}}_1^{*}\\ y_2\\ {-\mathrm{<figure-callout\; id="3"\; label="y"\; filenames="H2009100927539E00011.png,H2009100927539E00012.png"\; state="\{\{state\}\}">y</figure-callout>}}_3^{*}\end{array}\right]=\left[\begin{array}{cccc}{h}_{00}& h_{01}& 0& 0\\ {-h}_{01}^{*}& h_{00}^{*}& 0& 0\\ 0& 0& H_{20}& H_{21}\\ 0& 0& {-H}_{21}^{*}& H_{20}^{*}\end{array}\right]\left[\begin{array}{c}{S}_0\\ {-\mathrm{<figure-callout\; id="1"\; label="S"\; filenames="H2009100927539E00011.png,H2009100927539E00022.png"\; state="\{\{state\}\}">S</figure-callout>}}_1^{*}\\ T_0\\ {-\mathrm{<figure-callout\; id="1"\; label="T"\; filenames="H2009100927539E00011.png,H2009100927539E00022.png"\; state="\{\{state\}\}">T</figure-callout>}}_1^{*}\end{array}\right]+\left[\begin{array}{c}{N}_0\\ N_1\\ N_2\\ N_3\end{array}\right]---\left(6\right)$

Because $\left[\begin{array}{cccc}{h}_{00}& h_{01}& 0& 0\\ {-h}_{01}^{*}& h_{00}^{*}& 0& 0\\ 0& 0& H_{20}& H_{21}\\ 0& 0& {-H}_{21}^{*}& H_{20}^{*}\end{array}\right]$ Be orthogonal matrix, therefore can correctly detect S ₀, S ₁, T ₀, T ₁

Simultaneously, can find out that the channel matrix that each base station is constituted to the UE receiving terminal is a piece diagonal matrix, increase the number of base station, only increase the submatrix of diagonal matrix on diagonal, can not influence sending the detection of data symbol by formula (6).

At receiving terminal, the data symbol sequence that UE sends each base station receives respectively, detection and demodulation, obtains the soft bit sequence of each base station.The versions of data of sending according to each base station number is carried out bit with the soft bit sequence of each base station that obtains and is merged, and is combined the result again and deciphers.Particularly, testing process is as shown in Figure 4, and receiving terminal at first detects the data symbol that send each base station respectively according to channel estimating and formula (6), and output symbol detects sequence

With

To detect sequence respectively then With Send into demodulating unit and carry out demodulation separately, obtain soft bit sequence { s respectively ₀, s ₁, s ₂, s ₃And { t ₀, t ₁, t ₂, t ₃.

When transmitting terminal adopted Case1 to send data, the data symbol of transmission satisfied S ₀=T ₀, S ₁=T ₁, in view of the above to soft bit sequence { s ₀, s ₁, s ₂, s ₃And { t ₀, t ₁, t ₂, t ₃... Carrying out the bit merging, the soft bit sequence that again merging is obtained is sent into decoding unit and is deciphered;

When transmitting terminal adopted Case2 to send data, the data that send each base station all were about same code word, therefore can be with soft bit sequence { s ₀, s ₁, s ₂, s ₃And { t ₀, t ₁, t ₂, t ₃..., carrying out the bit merging according to the versions of data that send each base station, the soft bit sequence that merging obtains is sent into decoding unit and is deciphered.

As above, be under two kinds of sending modes, the transmission of carrying out cooperative multipoint transmission divides the concrete mode of collection and reception.In above-mentioned concrete implementation, be that example describes only with 2 transmit antennas, for other situation more than 2 transmit antennas, the present invention is suitable equally.Still can utilize each base station of participating in cooperative multipoint transmission, send identical or different versions of data to UE, and on different subcarrier resources, carry out SFBC, wherein, identical in the concrete mode of the SFBC of each base station and the LTE system.

Two through cooperative multipoint transmission in the invention described above are sent diversity mode; The transmission of on the SFBC basis of LTE, carrying out cooperative multipoint transmission among the LTE-Advanced divides collection; Do not change the SFBC transmission mode on each base station,, make receiving terminal realize that symbol level merges and bit level merging through on each base station, sending the identical or different versions of data of a code word; Improve the robustness of systematic function, help to improve the throughput of Cell Edge User.

Further, divide in the realization of collection, fix, then increase the number of base stations of participating in cooperation transmission, can also further improve transmission quality if data are sent the code modulation mode that is adopted in above-mentioned transmission.Based on this, can also be among the present invention further according to channel circumstance, the number of base stations of cooperative multipoint transmission is participated in the self adaptation adjustment.Particularly, given modulation coding mode carries out emulation to the SFBC of the invention described above in advance and confirms a sets of curves, is about the mapping relations between the signal to noise ratio (snr) under the different base station number and the error rate (BLER); Then, in real system, SNR value and object transmission quality BLER according to current channel circumstance select suitable number of base stations.Like this, according to the object transmission quality requirement of object UE, can adaptive adjustment number of base stations.

Above-mentioned two kinds of transmission diversity modes are compared, and the versions of data that send each base station among the case1 is identical, and the versions of data that send each base station among the case2 is different, so system's receptivity is better than Case1.The present invention sends diversity modes to above-mentioned two kinds and has carried out emulation respectively, and Fig. 3 is two kinds of simulation result comparison diagrams that send diversity modes, and wherein each bar curve shows the graph of a relation of SNR and system down link BLER under relevant parameter.Each bar curve corresponding parameters is as shown in table 1 among Fig. 3.

The curve numbering	Sending mode	Code check	Number of base stations
				301	Case1	0.5	2
302	Case1	0.85	2
				303	Case1	0.85	3
304	Case2	0.5	2
				305	Case2	0.85	2
306	Case2	0.85	3

Table 1

Visible by Fig. 3, under the identical parameters, the sending mode of case2 can obtain better system receptivity than the sending mode of case1; For with a kind of sending mode, number of base stations is many more, and system's receptivity is good more.

In addition, in practical application, the transmission branch collection that the mode that adopts case1 is carried out cooperative multipoint transmission can be set, promptly each base station supports the mode of case1 to send the branch collection; The mode that adopts case2 also can be set carry out the transmission branch collection of cooperative multipoint transmission, promptly each base station supports the mode of case2 to send the branch collection.

Certainly, more preferably, support case1 and case2 to send diversity mode for two kinds in each base station; UE also supports two kinds of method of reseptances of corresponding case1 and case2; In this case, in system's running, by the high-rise sending mode of confirming concrete employing of system; If the high-rise versions of data of notifying each base station to send is identical, then is the Case1 pattern; If the high-rise versions of data of notifying each base station to send is different, then is the Case2 pattern.And, the versions of data that system's high level utilizes each base station of control information notice UE to send.Wherein, system's high level can be confirmed the versions of data that send each base station according to the occupation condition and the disposal ability of current each base station.Behind the transmission diversity mode of confirming current employing, promptly can divide collection to realize carrying out SFBC according to aforesaid transmission, just repeat no more here.

Because the SFBC mode is all available under any channel circumstance, therefore transmission diversity mode of the present invention does not receive the restriction of channel transmission environment, with respect to existing mode, applicability is widely arranged.

More than being merely preferred embodiment of the present invention, is not to be used to limit protection scope of the present invention.All within spirit of the present invention and principle, any modification of being done, be equal to replacement, improvement etc., all should be included within protection scope of the present invention.

Claims (9)

1. the transmission deversity scheme of a cooperative multipoint transmission is characterized in that, this method comprises:

Participation is to each base station of the cooperative multipoint transmission of UE; The same versions of data of sending identical data to be transferred to said UE, and said each base station is carried out space frequency block coding SFBC to said data to be transferred at each inside of base station on different subcarrier resources.

2. method according to claim 1; It is characterized in that; In advance under the number of base stations of different participations to the cooperative multipoint transmission of said UE; The SFBC that carry out said data to be transferred on different subcarrier resources said each base station of emulation confirms corresponding different base stations number, the signal to noise ratio of system and the mapping relations between the error rate;

Signal to noise ratio according to current channel circumstance requires and target error rate, selects corresponding number of base stations, confirms to participate in each base station to the cooperative multipoint transmission of said UE.

3. method according to claim 1 and 2; It is characterized in that; This method further comprises: the data symbol sequence that said UE sends said each base station receives respectively and detects; And the symbol detection sequence of each base station is carried out demodulation respectively obtain soft bit sequence, the soft bit sequence of each base station that obtains is carried out bit merge, be combined the result again and decipher.

4. the transmission deversity scheme of a cooperative multipoint transmission is characterized in that, this method comprises:

Participation is to each base station of the cooperative multipoint transmission of UE; Send the different pieces of information version of identical data to be transferred to said UE, and said each base station is carried out space frequency block coding SFBC to said data to be transferred at each inside of base station on different subcarrier resources.

5. method according to claim 4; It is characterized in that; In advance under the number of base stations of different participations to the cooperative multipoint transmission of said UE; The SFBC that carry out said data to be transferred on different subcarrier resources said each base station of emulation confirms corresponding different base stations number, the signal to noise ratio of system and the mapping relations between the error rate;

Signal to noise ratio according to current channel circumstance requires and target error rate, selects corresponding number of base stations, confirms to participate in each base station to the cooperative multipoint transmission of said UE.

6. according to claim 4 or 5 described methods, it is characterized in that, utilize control information to issue the versions of data of sending said each base station number to said UE.

7. method according to claim 6; It is characterized in that this method further comprises: the data symbol sequence that said UE sends said each base station receives respectively and detects, and confirms the symbol detection sequence of said each base station; And the symbol detection sequence of each base station is carried out demodulation respectively obtain soft bit sequence; The versions of data of sending according to each base station number is carried out bit with the soft bit sequence of each base station that obtains and is merged, and is combined the result again and deciphers.

8. the transmission deversity scheme of a cooperative multipoint transmission is characterized in that, this method comprises:

The high-rise versions of data of confirming that each base station is sent to UE of system, and notify said UE the versions of data that send each base station, said each base station is for participating in each base station to the cooperative multipoint transmission of UE;

If the versions of data that send said each base station is identical; Confirm that then sending mode is case1; The same versions of data that data to be transferred is sent to said UE in said each base station, and space frequency block coding SFBC is carried out to said data to be transferred in said each base station on different subcarrier resources;

If the versions of data that send said each base station is different; Confirm that then sending mode is case2; Said each base station is to the different pieces of information version of said UE transmission data to be transferred, and space frequency block coding SFBC is carried out to said data to be transferred in said each base station on different subcarrier resources.

9. method according to claim 8 is characterized in that, said system high level is confirmed the versions of data that send said each base station according to the occupation condition and the disposal ability of current said each base station.

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