WO2007111198A1 - Transmission method and transmission device - Google Patents

Abstract

Provided is a transmission method in a single-carrier block transmission of a multi-antenna communication system hardly affected by a temporal fluctuation of a channel, having a simple structure, and especially appropriate for a multi-antenna communication system such as a multi-input multi-output (MIMO) antenna communication system. The transmission method diversity-transmits a single-carrier block and makes transmitted signals into a block by a blocking unit (402). The blocked signal is transmitted via a first antenna (406-1). Moreover, the blocked signal is conjugate-replaced by conjugate replacing units (403-1, 403-2) and weighted by weighting units (404-1, 404-2). The weighted signal is added in an addition unit (407) and transmitted via a second antenna (406-2).

Description

 Specification

 Transmission method and transmission apparatus

 Technical field

 TECHNICAL FIELD [0001] The present invention relates to a transmission method and a transmission apparatus that perform diversity transmission in single carrier block transmission of a multi-antenna communication system.

 Background art

 [0002] In wireless communication systems, attention is focused on performing high-rate data transmission in a high-speed mobile environment. This high-rate data transmission in a high-speed mobile environment is one of the major issues of how to cope with frequency selective channel dispersion in high-speed information transmission.

 [0003] For frequency-selective channel dispersion, the currently available efficient transmission techniques are mainly orthogonal frequency division multiplexing (OFDM) transmission techniques and frequency domain balancing (FDE). ) Based on! /, And two types of single carrier (SC) block transmission technology are known. For example, Non-Patent Document 1 describes single carrier transmission technology.

 [0004] The SC block transmission technology will be described below.

 [0005] In OFDM transmission technology, data is transmitted in the frequency domain, whereas in SC block transmission technology, data is transmitted in the time domain. Therefore, SC transmission technology uses peak-to-average compared to OFDM transmission technology. The power ratio (PAPR) is low.

 [0006] It is very important for PAPR to be low for improving the utilization rate of transmission power, reducing the degree of signal distortion, and the quantization order.

 [0007] In OFDM transmission technology, when a parallel data stream in the frequency domain is converted to the time domain and transmitted, a high PAPR power is exerted. In terms of ease of implementation, when FDE technology is adopted, the ease of implementation of SC block transmission technology is almost the same as that of OFDM transmission technology.

[0008] For these reasons, SC block transmission technology has the highest demand for low PAPR in 3GPP Long-Term Evolution (LTE), and is the most effective transmission used in the uplink. It is considered as a means. FIG. 1 is a diagram showing a configuration of a conventional single antenna SC block transmission system.

[0010] On the transmission side, first, the coding unit 101 and the modulation unit 102 perform channel coding and constellation modulation on the data stream to be transmitted. The modulated serial code stream is divided into blocks (block length is N).

[0011] Thereafter, the GI insertion unit 104 performs a guard interval between data blocks.

 Insert (GI) and transmit from antenna 105. In the GI insertion unit 104, as in the OFDM system, a cyclic 'prefix (CP) is generally inserted before each data block. That is, the last N data of each data block is copied and the data block is copied. Ahead

 G

 Place on the head. Where N is the length of the GI, less than the maximum delay time length of the channel

 G

 It is required to be.

 On the other hand, on the receiving side, first, a spatial signal is received by the receiving antenna 111. Then, channel estimation section 118 performs channel estimation based on the no-lot signal in the received signal or using another method, and estimates the current time-domain channel impulse response h. At the same time, the GI removal unit 112 removes the GI part from the received signal. Further, in each of the fast Fourier transform unit 113, the frequency domain balancing unit 114, and the inverse fast Fourier transform unit 115, N points of fast Fourier transform (FFT), FDE ( Frequency domain balancing) and N-point inverse fast Fourier transform (IFFT). Here, the frequency domain balancing unit 114 performs frequency domain balancing on the signal using the current channel characteristics acquired by the channel estimation unit 118. Subsequently, the demodulated unit 116 and the channel decoding unit (decoding unit) 117 sequentially perform demodulation and channel coding processing on the balanced output signal, and finally the original transmission data is acquired. The

 As described above, transmission and reception in the SC block transmission system referred to here are performed in units of data blocks.

h(l),- --, h(Lc-l)}として示すことができる。そこで、 GI除去装置 112の 処理を経た後の時間領域の第げロックにおける第 n信号は下記式（1)のように表すこ とがでさる。 [0014] Single carrier transmission (FDE: Single carrier systems with Frequency Domain Equalization) technology using frequency domain equalization in such SC block transmission; ¾ further uses the following mathematical form: Can be expressed. First, the transmission and balance method in the SC transmission method of the conventional single antenna communication system will be described. [0015] First, the channel is an Lc stage finite impulse response (FIR) filter, that is, a channel impulser.

h (l), ---, h (Lc-l)}. Therefore, the n-th signal in the time domain lock after the processing of the GI removal device 112 can be expressed as the following equation (1).

[Number 1]

[0016] However,

 [Equation 2]

Κ (")} — J represents the N data transmitted by the i-th data block, (k) represents the remainder after kmodN, and n (

 N

 n) represents an additive white Gaussian noise (AWGN).

[0017] From the above equations, it can be understood that the SC transmission technique is sufficiently similar to the OFDM transmission technique in terms of signal format, and both are the result of circular convolution of the transmission signal and the channel impulse.

 In the frequency domain, in other words, after the received signal is FFTed, it can be expressed as the following equation (2) as a result of multiplication of the transmission signal frequency domain and the channel frequency domain.

[Equation 3]

¾ (Ar) = H () S () + N () Q≤k≤N-\ · " ₍₂₎ where R (k) is at the kth point in the frequency domain after FFT of the i-th received data block H (k) is the numerical value at the kth point in the channel frequency domain, S (k) is the numerical value at the kth point in the frequency domain after the FFT of the i th transmission data block, and N (k ) Represents the numerical value at the k-th point in the noise frequency region.

[0019] Therefore, the SC signal can be balanced by a simple FDE scheme such as zero forcing (ZF) balancing and least square error (MMSE) balancing. [0020] Further, the equilibrium key operator is W = {W (0), W (1),, W (N-1)}, where W (k) is the balance key operator in the frequency domain subcarrier k. In other words, the time-domain signal output after passing through FDE and IFFT can be expressed by the following equation (3).

Η = / r {^ (0)} ¥ (0), ^ (1) ^ (1), ..., R ,. (N-l) W (N-l)} ... ₍₃₎

[0021] When ZF equilibrium is adopted, W (k) = lZH (k). When MMSE equilibrium is adopted,

 [Equation 5]

W (k).

\ H (k) \ ² ₊ V p Where is the signal-to-noise ratio (SNR).

 Next, a transmission diversity method in SC block transmission will be described.

[0023] As described above, multi-antenna transmission technology (MIMO) is an important transmission means in next-generation wireless communication!

 [0024] In the MIMO system, the transmitting side transmits signals using a plurality of antennas, and the receiving side receives spatial signals using a plurality of antennas. Research has shown that MIMO technology can effectively improve transmission rate and performance compared to conventional single antenna transmission methods.

 [0025] By combining this MIMO technology with SC block transmission technology, it is possible to realize high-speed data transmission over a frequency-selective channel. Based on the idea that uplink transmission power is limited, LTE has proposed to adopt a transmission method that combines SC and multi-antenna transmission diversity in LTE! .

 [0026] In recent years, a single transmission diversity method used for SC block transmission has been shown and has attracted wide attention, and this method is regarded as an extension of the conventional Alamouti transmission diversity in SC block transmission. Can do. Figure 2 shows the configuration that implements this method.

[0027] FIG. 2 is a diagram for explaining transmission diversity of SC block transmission in a conventional multi-antenna communication system. On the transmission side, a data stream to be transmitted is first subjected to channel code modulation and constellation modulation by a channel encoding / modulation unit 201. The channel encoded 'constellation-modulated data stream is blocked by the blocking unit 202. The length of each code block after blocking is N.

 [0029] After that, the space-time block code decoder 203 performs space-time block code processing on two adjacent code blocks, and two data blocks each corresponding to one transmission antenna are obtained. Is output. In each output data block, the GI insertion unit 204 inserts a guard interval. Finally, each data block in which the guard interval is inserted is transmitted from the corresponding transmission antenna 205. In this case, the format of transmission data in the two antennas is as shown in FIG.

 FIG. 3 is a diagram showing a format of each antenna data in transmission diversity of SC block transmission in a conventional multi-antenna communication system. Txl and Τχ2 represent transmission data (antenna data) transmitted from each antenna.

In FIG. 3, the signal of the previous i-th block in the space-time block code section 203 is represented by s = [s (0), s (l), ~, _S (Nl)] ^T , and has a length Let N be N and T represents the matrix transpose.

 [0032] As shown in FIG. 3, antenna 1 and antenna 2 are connected to signal s = [s (0),

2i 2i s (l), "', s (N-1)] ^T and s = [s (0), s (l),-, s (N-1)] ^T are transmitted respectively.

2i 2i 2i + l 2i + l 2i + l 2i + l

 Antenna 1 and antenna 2 are signals at the timing of block 2i + l-s * ((N-n)) = [-s * (0),-s *

 2i + l N 2i + l

(N- 1), ...,-s * (1)] ^T and s * ((Nn)) = [s * (0), s * (N- l), "', s * (1) ] Send ^T each

2i + l 2i + l 2i N 2i 2i 2i

 To do. Where (x) is the remainder taken by x vs. N.

 N

 When transmitting in the data format shown in FIG. 3, the frequency domain format of the signals in the two transmission antennas is as shown in FIG. 4 according to the correlation theory of mathematical signal processing.

FIG. 4 is a diagram showing the frequency domain format of each antenna data in transmission diversity of SC block transmission in a conventional multi-antenna communication system.

In FIG. 4, the frequency domain signal of the i-th block signal s = [s (0), s (l),--, s (Ν- 1)] is expressed as S = [S (0 ), S (1), ~, S (N-1)], S = FFT {s}. Therefore, as shown in Figure 4, The frequency domain signals transmitted by antenna 1 and antenna 2 at the timing of block 2i are S = [S (0), S (1), "', S (N-1)] ^τ and S = [S (0 ), S (1),--, S (N- 1)] ^T

 2i 2i 2i 2i 2i + 1 2i + 1 2i + 1 2i + 1

The In addition, the frequency domain signals transmitted by antenna 1 and antenna 2 at the timing of block 2i + l are — S * = [— S * (0), — S * (1), ..., — S * ( N- 1)] ^τ and S * = [S *

 2i + l 2i + l 2i + l 2i + l 2i

(0), S * (1),-, S * (N— 1)] ^T.

 2i 2i 2i

 [0036] In addition, in the same subcarrier k, it can be found that the signals in the frequency domain in two adjacent blocks of two antennas form a conventional Alamouti signal configuration, for example, The frequency domain format of the transmission signal in subcarrier k is as shown in Table 1 below. Table 1 below shows the frequency domain format of the transmitted signal in subcarrier k.

[table 1]

 [0037] According to the MIMO correlation theory, the advantage of Alamouti transmission diversity is that the receiving side can acquire the maximum likelihood (ML) by simple linear detection, and thus can acquire effective transmission diversity performance. The configuration of the receiver that performs SC block transmission diversity shown in Fig. 3 is as shown in Fig. 5.

 FIG. 5 is a diagram showing a configuration of a receiving apparatus in transmission diversity of conventional SC block transmission.

 [0039] As shown in FIG. 5, on the receiving side, two adjacent transmission blocks are first received with n reception blocks.

 R

All signals in the space are received by the antenna 301, and channel estimation is performed by the channel estimation unit 309 based on the pilot signal in the received signal or using other methods, and the current (during reception) Estimate channel characteristics. Then, the GI removal unit 302 performs a GI removal operation on the received signal at each antenna. After the GI removal, the serial Z parallel conversion unit 303 and the FFT unit 304 receive the received signal of each reception antenna. On the other hand, serial Z parallel conversion and FFT operations are performed. After that, the frequency received by n receiving antennas in MIMO-FDE section 305 FDE operations are performed on the signals in the area all at once. Here, MIMO-FDE section 305 performs balancing for each subcarrier, that is, four frequencies transmitted in two blocks adjacent to two antennas on the same subcarrier. For the domain signal, linear frequency domain balance is performed collectively by the conventional Alamouti method. Subsequently, IFFT conversion section (indicated by “IFFT section” in the figure) 306 performs IFFT operation on the two systems of signals from which the MIMO-FDE section 305 output is also output. Parallel Z-serial conversion is performed. The two systems of signals subjected to parallel Z-serial conversion are subjected to code demodulation and channel decoding in a demodulation / decoding unit 308, and finally output as original transmission data.

 Non-patent document 1: "Study of optimal roll-off factor of spectrum shaping filter for Evolved UTRA uplink single-carrier wireless access" IEICE, RCS2005 — 148, January 2006

 Disclosure of the invention

 Problems to be solved by the invention

[0040] However, as can be understood from the conventional Alamouti transmission correlation theory, this kind of transmission diversity method is relatively susceptible to channel time fluctuations, so that the channel characteristics in adjacent SC blocks Is required to be unchanged. This requirement is often difficult to meet in the next generation of actual systems due to the following two reasons.

 [0041] One of the causes is that high-speed information transmission in next-generation wireless communication is performed for a larger number of high-speed mobile users, and therefore it is possible to avoid channel time fluctuations caused by high-speed movement of mobile stations. Can not.

[0042] As can be understood from the configuration of the SC block transmission system, the other cause is that each SC block is generally much longer than the code interval that is long in time (for example, one thousand transmission codes are included in one block). Therefore, it is difficult to make the channel unchanged for a long time.

[0043] Thus, in the prior art, the channel time fluctuation in the adjacent SC block prevents orthogonality in the frequency domain of the received signal, which leads to poor reception performance. There is a title. Therefore, in MIMO-SC block transmission technology, there is a demand for a transmission diversity method used for SC block transmission that is << and simple in response to the effects of channel time fluctuations.

 [0044] An object of the present invention is not easily affected by channel time fluctuations, is simple, and particularly suitable for a multi-antenna communication system such as a multi-input 'multi-output (MIMO) antenna communication system. It is another object of the present invention to provide a transmission method and a transmission apparatus in single carrier block transmission of a multi-antenna communication system.

 Means for solving the problem

 [0045] The transmission method of the present invention is a transmission method for diversity transmission of a single carrier block, in which a blocking step for blocking a signal to be transmitted and a blocked signal are transmitted via a first antenna. A first transmission step, a conjugate replacement step for conjugate replacement of the blocked signal, a weighted addition step for weighted addition of the conjugate replaced signal, and the weighted signal through the second antenna. And a second transmission step for transmission.

 [0046] The transmission apparatus of the present invention is a transmission apparatus that diversity-transmits a single carrier block, and includes a blocking unit that blocks a signal to be transmitted, a first transmission antenna that transmits the blocked signal, A configuration is employed that includes a conjugate replacement unit that conjugate replaces the blocked signal, a weighted addition unit that weights and adds the conjugate replaced signal, and a second transmission antenna that transmits the weighted signal.

 The invention's effect

 [0047] According to the present invention, it is possible to suitably cope with performance deterioration due to the influence of channel time variation, and it is possible to maintain the simplicity of transmission and reception.

 Brief Description of Drawings

[0048] [FIG. 1] A diagram showing a configuration of a conventional single antenna SC block transmission system.

 [Fig. 2] Diagram for explaining transmit diversity of SC block transmission in a conventional multi-antenna communication system

[Fig. 3] A diagram showing the format of each antenna data in transmission diversity of SC block transmission in a conventional multi-antenna communication system [Fig. 4] A diagram showing the frequency domain format of each antenna data in the transmission diversity of SC block transmission in a conventional multi-antenna communication system.

 FIG. 5 is a diagram showing a configuration of a receiving apparatus in transmission diversity of a conventional multi-antenna SC block transmission.

 FIG. 6 is a block diagram of a transmission apparatus used for explaining the transmission method according to the embodiment of the present invention. FIG. 7 is a transmission diversity of multi-antenna SC block transmission used for explaining the transmission method according to the embodiment of the present invention. Of each antenna data format

 FIG. 8 is a diagram showing a frequency domain format of each antenna data in transmission diversity of multi-antenna SC block transmission used for explaining a transmission method according to an embodiment of the present invention.

 FIG. 9 is a diagram showing a configuration of a receiving apparatus that receives a transmission signal of the transmitting apparatus according to the embodiment of the present invention.

 FIG. 10 is a diagram for explaining the performance comparison between the transmission method and the conventional transmission method in the transmission apparatus according to the present invention.

 BEST MODE FOR CARRYING OUT THE INVENTION

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

[0050] FIG. 6 is a block diagram of a transmission apparatus for explaining the transmission method according to the embodiment of the present invention. FIG. 6 is a block diagram of a transmission apparatus showing the configuration of transmission diversity for multi-antenna SC block transmission.

[0051] Transmitting apparatus 400 shown in FIG. 6 includes encoding / modulation section 401, blocking section 402, and conjugate substitution section.

 (First conjugate replacement unit 403-1, second conjugate replacement unit 403-2) and weighting unit (first weighting unit 404

-1, second weighting unit 404-2), addition unit 407, guard interval (GI) insertion unit 405-1, 4

05-2, first transmitting antenna 406-1 as multiple transmitting antennas, second transmitting antenna 406-

And 2.

 [0052] Encoding 'modulation section 401 performs channel coding and constellation modulation on the data stream to be transmitted, and outputs the result to blocking section 402.

[0053] Blocking section 402 blocks the channel code key and the constellation-modulated data stream, and transmits it from two transmission antennas 406-1 and 406-2. Output to insertion section 405-1 and conjugate replacement sections 403-1 and 403-2. Note that the length of each code after blocking output from the blocking unit 402 is N.

[0054] The GI insertion unit 405-1 directly inserts a card interval between the blocked signals and transmits the signal via the transmission antenna 406-1.

[0055] Conjugation replacement sections 403-1 and 403-2 are arranged as a system of signals transmitted by second transmission antenna 406-2, and with respect to the original blocked signal from blocking section 402. In either case, the combination replacement process is performed, and the respective signals are output in parallel to the weighting sections 404-1 and 404-2.

 [0056] Weighting sections 404-1, 404-2 perform weighting processing (described later) using eigensequences on signals input in parallel from conjugate substitution sections 403-1, 403-2, And output to the adder 407.

 [0057] These conjugate replacement sections 403-1 and 403-2 and weighting sections 404-1 and 404-2 perform two systems of parallel processing on the blocked signal transmitted from the other transmitting antenna 406-2. I do.

 [0058] Adder 407 adds the signals input in parallel from weighting sections 404-1, 404-2, and outputs the result to GI insertion section 405-2. The adding unit 407 constitutes a weighted adding unit together with the weighting units 404-1 and 404-2.

 [0059] The GI insertion unit 405-2 directly inserts and outputs a card interval between the input blocked signals, and transmits the signal via the second transmission antenna 406-2.

 [0060] First transmission antenna 406-1 and second transmission antenna 406-2 each transmit a signal using adjacent subcarriers. For convenience, the first transmitting antenna 406-1 is also referred to as transmitting antenna 1 or antenna 1, and the second transmitting antenna 406-2 is also referred to as transmitting antenna 2 or antenna 2. The format of transmission data in two transmission antennas (here, first transmission antenna 406-1 and second transmission antenna 406-2) is as shown in FIG.

 FIG. 7 is a diagram showing a format of each antenna data in the transmission diversity of multi-antenna SC block transmission for explaining the transmission method according to the present invention. Tx 1 and Τχ 2 represent transmission data transmitted from each of the first transmission antenna 406-1 and the second transmission antenna 406-2.

In FIG. 7, the signal of the first block after being blocked is represented by 5 = [5 (0), 5 (1) ′, 5 −1)] ^1> Suppose the length is N and T represents the matrix transpose.

[0063] As shown in FIG. 7, in the transmission apparatus 400 (see FIG. 6), the first transmission antenna 406-1 and the second transmission antenna 406-2 are connected at the timing of the block i with the signal s = [s (0) , s (1), · ", s (Ν- 1)] ^τ and Ps * = Ρ [s * (0), s * (l), ---, s * (N- 1)] ^T However, P = W P + WP, P and

 1 i i 1 1 2 2 1 and P correspond to operations by conjugate substitution units 403-1 and 403-2, respectively, and W and W are

 2 1 2 Corresponds to the operations in the weighting units 404-1, 404-2.

[0064] Specifically, the signal processing process before inserting the GI at the second transmitting antenna, specifically, conjugate replacement units 403-1 and 403-2, weighting units 404-1 and 404-2 The processing in includes the following steps.

 (0065) Conjugate substitution is performed on the blocked signal. This signal processing is performed by the conjugate substitution units 403-1 and 403-2.

[0066] Here, the first lock signal 3 = “3 (0), 3 (1) ′, 3 ^ −1)] ^1> after blocking is first obtained after conjugation is performed. In other words, the operation is to change the position of each signal in the original data block, and in mathematics, the replacement operation can be expressed using a left-hand permutation matrix. NX N matrix P

 It can be expressed by 1 and P. Therefore, the two signals after conjugate substitution are P

 2

 It can be expressed as s * and P2s *. However,

 [Equation 6]

P,

 ..., Ν

i=l, ...,Ν; j=l, ...,Ν である _c [0067] (2)置換後の信号に対して固有シーケンス重み付けを行う。なお、この信号処理は、 重み付け部 404-1 ,404-2にて行われる。 as well as

i = l, ..., Ν; j = l, ..., _{c with} Ν (2) Eigensequence weighting is performed on the signal after replacement. This signal processing is performed by the weighting units 404-1 and 404-2.

[0068] Here, eigensequence weights are applied to the signals P s * and P s * after conjugate substitution, respectively.

 1 i 2 i

 However, the sequence weighting operation can be expressed using a left-right diagonal matrix. In FIG. 6, the eigensequence weighting operation of the signal of system 2 can be expressed by N X N diagonal matrices W and W, respectively. Therefore, 2 after sequence weighting

 1 2

 The system signals can be expressed as W P s * and W P s *, respectively. However,

 1 1 i 2 2 i

 [Equation 7]

_{ΤΓ J} f. 2π 0 _.2π (Ν-V) 2π (Ν -2) 2π -0)

 W. = dtag J-/ sin, -zo sin ^, zo sin ~~, ..., one zo sin 1

^{1 &} \ ^J NNNNJ

 „,, (2π-(Ν / 2) 2π {ΝΙ2-\) 2π · 0 2π · (Ν— 1) 2π-(Ν-2) 2π-(Ν / 2 + ί)}

W,-rf / ae J -cos— ^ -cos ™ ~-, .... -cos, one cos-, -cos -cos 1

^{2 s} j NNNNNNJ.

 [0069] (3) A sum is obtained for the signals after the two systems of parallel processing. This signal processing is performed by the calorie calculation unit 407, and finally, the addition unit 407 finally obtains the signal W P s * + W P

 1 1 i 2 2

S * is obtained.

 [0070] When signal transmission is performed using the transmission apparatus 400 according to the present invention shown in FIG. 6, that is, when transmission diversity of multi-antenna SC block transmission is performed, the frequency domain signal as shown in FIG. You can get the format.

[0071] FIG. 8 is a diagram showing a frequency domain format of each antenna data in transmission diversity of multi-antenna SC block transmission for explaining the transmission method according to the embodiment of the present invention.

[0072] Here, the frequency domain signals transmitted by the first transmitting antenna 406-1 and the second transmitting antenna 406-2 are respectively S = [S (0), S (1), "', S (N -1)] ^τ and S, = [— S * (1), S * (0), -S * (3), S * (2), · S * (N- 1), S * (N -2)] ^T.

[0073] As can be understood from FIG. 8, in the transmission device 400 of the present invention, the signals in the frequency domain in the two subcarriers 2k and 2k + 1 adjacent to the two antennas are as shown in Table 2 below. This is exactly the conventional Alamouti signal structure. Table 2 below shows the frequency domain format of the transmitted signal in subcarriers 2k and 2k + 1. [Table 2]

 [0074] As described above, this type of transmission scheme requires that channel characteristics corresponding to two signals transmitted by the same antenna be as unchanged as possible.

 [0075] In the conventional method, as shown in Table 1, two signals on the same antenna are transmitted in two adjacent blocks in time, and the mobile station moves fast and the block length is long. It was often difficult to meet this condition.

 On the other hand, in the present invention, as shown in Table 2, the transmitter apparatus 400 transmits two signals on the same antenna on two subcarriers adjacent in the frequency domain. Transmitting apparatus 400 is obtained by converting the spatial one-time transmission diversity of the frequency domain signal in the conventional transmitting apparatus into spatial frequency transmission diversity.

 [0077] From the related theory, it can be understood that the channel characteristics of adjacent subcarriers in the frequency domain have a strong correlation, and the two are almost the same. In other words, the method of the present invention can be suitably applied without suffering from performance degradation due to the influence of channel time variation.

 [0078] Note that the MIMO-SC transmission method used in the transmission apparatus 400 according to the present invention is illustrated in FIG.

 Reception can be performed using the receiving device shown in FIG.

FIG. 9 is a diagram showing a configuration of a receiving apparatus that receives a transmission signal of the transmitting apparatus according to the embodiment of the present invention.

 In the receiving device 500 shown in FIG. 9, the reception process of the transmission signal from the transmitting device 400 is illustrated in FIG.

 Compared with the conventional SC block transmission transmission diversity method in the receiving apparatus shown in FIG. 5, the only difference is that the frequency domain balancing unit 510 performs frequency balancing.

[0081] Reception apparatus 500 includes reception antenna 301, channel estimation unit 309, GI removal unit 302, serial Z parallel conversion unit 303, FFT unit 304, IFFT conversion unit 306, and parallel Z serial conversion. Unit 307, demodulation / decoding unit 308, and frequency domain balance unit 510 instead of MIMO-FDE unit 305. In receiving apparatus 500, channel characteristics are estimated by channel estimating section 309, and signals input via receiving antenna 301, serial Z / parallel converting section 303, and FFT section 304 are transmitted to two antennas of transmitting apparatus 400. This is a signal in the frequency domain of two adjacent subcarriers 2k and 2k + l.

 [0083] Frequency domain balancing section 510 performs a balance function for each of the two subcarriers for the frequency domain signals in subcarriers 2k and 2k + l forming the input Alamouti signal configuration. Output to IFFT converter 306 as two signals.

 [0084] Specifically, the conventional MIMO-FDE unit 305 performs balancing for each subcarrier, that is, two blocks on the same subcarrier and adjacent to each other with two antennas. For the four frequency domain signals transmitted in the network, linear frequency domain balancing is performed collectively using the conventional Alamouti method!

 On the other hand, in receiving apparatus 500 in the present embodiment, frequency domain balancing section 510 converts four antennas into four frequency domain signals transmitted on two adjacent subcarriers 2k and 2k + 1. On the other hand, linear frequency balance is performed collectively by the conventional Alamouti method. The balanced key algorithm is exactly the same as the conventional method, and the input is different. In other words, the input of the balanced section is derived from the “four frequency domain signals transmitted in two blocks on the same subcarrier on which two antennas are adjacent” in the conventional method. Instead of two subcarriers 2k and 2k + l, the four frequency domain signals transmitted are transmitted.

 FIG. 10 is a diagram for explaining the performance comparison between the transmission method and the conventional transmission method in the transmission apparatus according to the present invention, and shows the result of the performance comparison by each transmission method.

The channel model adopted in the performance comparison simulation shown in FIG. 10 is ITU M.1225 channel model A, the channel bandwidth is 10 MHz, and N = 1024. The number of transmitting and receiving antennas is 2 and 1, respectively, and QPSK modulation is adopted.

 [0088] In FIG. 10, f is the maximum Doppler frequency shift, and T is the time of each transmission block.

 d

 Long.

[0089] As can be seen from FIG. 10, with the conventional method, as the channel time variation increases, The performance is gradually worsening. In contrast, the method of the present invention can effectively counter the performance penalty caused by channel time variations, and the transmission and reception methods still remain simple. Compared to the conventional method, the transmission side is only a weight 2 system weighting using a weighting operation, and the weighting sequence is a positive cosine signal sequence. small ,.

Next, the format of the frequency domain signal (see FIG. 8) when transmitted by the transmission apparatus 400 according to the present invention shown in FIG. 6 will be described in detail.

[0091] If the frequency domain signal at the first transmitting antenna 406-1 is S = [S (0), S (1), ···, S (Ν-1)] ^τ , the second transmitting antenna 406- Frequency domain signal S, = [-S * (l), S),-S * (3), S * (2), •••, -S * (Nl), S * (N-2) ] ^T can be expressed as S '= (AS) *.

 Where A is an N X N matrix,

 [Equation 8]

 It becomes. Assuming that an N X N matrix C exists and FFT s} = AS, FFT {BC * s *} = (AS) * due to the correlation theory of signal processing. However,

 [Equation 9]

 It is. In the following, the solution of C will be intensively obtained. If F is an FFT matrix,

 N

[Equation 10]

It becomes. And by reasoning [Equation 11]

C = F _N "AF _N is derived, ie

 [Equation 12]

 N N

 = 丄 W zo 2 [(,-l) («-l)-("-lX *-], and further simplification based on the decimation property of the Α matrix

[[(Le lX2 _m — l)-(2m— 2X 1)] _ [(Le lX2m-2) — (2 _m -lX * r— 1)]]

 Is obtained and last

 ".. 2jt (k-l)

¹ zone sin-- -

N

 Cos \ l-k \-Nll

 N

 0 others are obtained, and it is proved that W P + W P = BC *.

 1 1 2 2

 [0092] As described above, the present invention will be described by showing a preferred embodiment of the present invention! It is obvious to those skilled in the art that various changes, substitutions, and additions can be made without departing from the spirit and scope of the present invention. Therefore, it should be understood that the present invention is not limited to the above-described embodiments, but is limited by the appended “claims” and their equivalents. That is, the present invention is not limited to the above-described embodiment, and can be implemented with modifications without departing from the gist thereof.

 [0093] The transmission device according to the present invention can be mounted on the communication terminal device and the base station device in the communication system, and thus the communication terminal device and the base station device having the same operational effects as described above. Can be provided.

[0094] Although the case where the present invention is configured by nodeware has been described as an example here, the present invention can also be realized by software. For example, a function similar to that of the apparatus according to the present invention is realized by describing the algorithm of the transmission method according to the present invention in a program language, storing the program in a memory, and executing it by an information processing means. can do.

 [0095] The disclosure of the description, drawings and abstract contained in the Chinese application of No. 200610071419.9 filed on March 20, 2006 is hereby incorporated by reference.

 Industrial applicability

[0096] The transmission diversity method in the single carrier transmission of the multi-antenna communication system according to the present invention has an effect that is difficult to be affected by the time variation of the channel and has a simple effect. This is useful as a multi-antenna communication system such as an antenna communication system.

Claims

The scope of the claims  [1] A transmission method for diversity transmission of a single carrier block,  A blocking step for blocking the transmitted signal;  A first transmission step of transmitting a blocked signal through a first antenna; a conjugate replacement step of conjugate replacing the blocked signal;  A weighted addition step for weighted addition of the conjugate-substituted signal;  A second transmission step of transmitting the weighted and added signal via the second antenna;  [2] In the first transmission step and the second transmission step, signals s and Ps * are transmitted at the timing of block i by the first transmission antenna and the second transmission antenna, and P is P = WP + WP Satisfying the relationship, and P and P are each in parallel processing 1 1 2 2 1 2  Is a permutation matrix, and W and W are each a feature sequence in parallel processing of two systems.  1 2  The transmission method according to claim 1, wherein the transmission weighting matrix is used.  [3] [Equation 1] = l, ..., N; j =] One

i = l, ..., N; j = l ".., N;  2 -0. 2π (Ν ~ \)., 2π (Ν -2). 2πΌ W _x = diag -j sm, ー zo sin ~~ ― sm ^…, —j si]  N N N N; and 2π · (Ν / 2) 2π (Ν / 2- \) 2π · (Ν- \) 2π · (Ν-2) 2π- (Ν / 2 + \) W ₂ -diag  3. The transmission method according to claim 2, wherein N N N N N N. [4] In the first transmission step and the second transmission step, the first antenna and the The signal transmitted by each of the second antennas is a frequency domain signal S = [S (0), S (l), ---, S (send to two adjacent subcarriers 2k and 2k + l. N-1)] ^T and S '= [-S * (l), S * (0), -S * (3), S * (2), ..., -S * (N-1), 2. The transmission method according to claim 1, wherein S * (N−2)] ^T , and the frequency domain signals in the two adjacent subcarriers 2k and 2k + 1 have a configuration of an Alamouti signal.  [5] Four frequency domain signals transmitted by two adjacent subcarriers 2k and 2k + 1 transmitted by the first antenna and the second antenna, respectively, are transmitted to the receiving side. 5. The transmission method according to claim 4, wherein the linear equilibrium is performed in a batch by the Alamouti method. [6] A transmission device for diversity transmission of a single carrier block,  Blocking means for blocking the transmitted signal;  A first transmit antenna for transmitting the blocked signal;  A conjugate replacement unit for conjugate replacement of the blocked signal;  A weighted addition unit for weighted addition of the conjugate-substituted signal;  A transmission apparatus comprising: a second transmission antenna that transmits a weighted signal.