JP2002171207A - Cdma communication equipment and cdma communication method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform highly precise demodulation when applying a common already known signal to selective transmission diversity. SOLUTION: A correlation calculating part 213 calculates a correlation value between a reception signal and codes CCd#1 and SC#1 based on a receiving timing outputted from a path selecting part 211, and a reception power averaging part 215 averages this correlation value by a plurality of symbol units. A correlation calculating part 214 calculates a correlation value between the reception signal outputted from a storage part 201 and the codes CCd#1 and SC#1 based on the receiving timing outputted from the path selecting part 212, and a reception power averaging part 216 averages the correlation value by a plurality of symbol units. A selecting part 217 compares a mean value outputted from the reception power averaging part 215 with a mean value outputted from the reception power averaging part 216, and a demodulating part 205 selects the receiving timing according to the compared result of the selecting part 217, and demodulates the reception signal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a CDMA communication apparatus and a CDMA communication method, and more particularly to a CDM to which both a common known signal and selective transmission diversity can be applied.
A communication device and a CDMA communication method.

[0002]

2. Description of the Related Art Code division multiple access (CDMA) using spread spectrum communication as a multiple access (multiple access) method in which a large number of communication devices communicate with each other.
s: code division multiple access) system. The CDMA system is
TDMA (Time Division Multiple Access) and FDMA (Frequency Division Multi Access)
It has the characteristics that higher frequency efficiency can be obtained as compared with the ple Access (code division multiple access) method and that more users can be accommodated.

Conventionally, the CDMA system sometimes employs a midamble as a known signal used for channel estimation and the like. The midamble is generated by shifting a known basic code circulating in a predetermined chip cycle by a predetermined chip unit.

FIG. 12 is a schematic diagram showing a procedure for creating a midamble in a CDMA wireless communication system. Here, a procedure for creating a midamble when eight different blocks are used will be described.

As shown in FIG. 12, each pattern of the midamble (hereinafter referred to as "midamble pattern").
Is created according to the following procedure using a basic code circulating at a cycle of 456 (= 8 W) chips. Note that this basic code is known to both the base station and the communication terminal device, and includes eight different blocks A to H. Each of the blocks A to H has a length of 57 (= W) chips.

First, as a first step, the phase of the basic code is shifted from the reference time by {W × (n-1)} chips to the right in the figure. Here, n is the basic code shift number (midamble shift).
The number of chips to be shifted is 0, W,..., 7W in the case of midamble shift 1, midamble shift 2,.

As a second step, for each shifted basic code, with respect to a certain block, other portions except for 456 chips from the leading end of this block are deleted. Here, the block A is used as a reference as an example.

As a third step, each code left by 456 chips is circulated leftward in the figure by {W × (n-1)} chips. For example, in the case of midamble shift 2, the code left by 456 chips is circulated leftward in the figure by W chips, and block B is located at the left end of the code. , E, F, G, H
Then, block A is positioned at the end (right end) of the code.

As a fourth step, the same block as the leading block in each code after the circulation is added to the end to form a 512-chip length code as a whole, and this code is used as a midamble pattern of each midamble shift. For example, in the case of the midamble shift 2, the same block B 'as the first block B after the circulation is added to the end to form a midamble shift 2 midamble pattern.

[0010] When the transmitting side uses such a midamble for a known signal, the receiving side can synchronize the signal of each individual channel at a time by correlating with the basic code.

In recent years, in a radio communication system, space diversity has been adopted in which a base station apparatus has a plurality of antenna branches to secure a plurality of paths. As one of the space diversity, there is a selection diversity for selecting an optimum antenna branch according to a propagation state. Hereinafter, a technique using the selection diversity on the transmission side is referred to as selection transmission diversity. This selective transmission diversity can transmit a signal by selecting a propagation path with the best propagation environment from a plurality of propagation paths, so that the effect of fading can be reduced.

[0012]

Here, when the selective transmission diversity is applied, the delay time and the phase rotation are different between signals transmitted from different antenna branches due to differences in propagation paths. Due to the difference between the delay time and the phase rotation, the timing of the code multiplication in the despreading process differs for each propagation path.

Therefore, if the common midamble is applied as it is to the selected transmission diversity and the transmission side transmits the midamble from one antenna branch, the reception side can obtain only the timing of code multiplication for one propagation path. It is difficult to accurately demodulate a received signal that has passed through the propagation path.

[0014] The present invention has been made in view of the above points, and an object of the present invention is to provide a CDMA communication apparatus and a CDMA communication method capable of accurately demodulating when a common known signal is applied to selective transmission diversity. I do.

[0015]

SUMMARY OF THE INVENTION A CDMA communication apparatus according to the present invention includes a plurality of antenna branches and an antenna branch selecting means for selecting, for each data signal, an optimum antenna branch for transmitting a data signal in accordance with a propagation path condition. And transmitting means for transmitting each data signal from an optimal antenna branch and transmitting a different common known signal for each antenna branch.

The CDMA communication apparatus according to the present invention comprises the same number of multiplexing means as the number of the antenna branches for forming a frame by time-multiplexing a data signal and a common known signal for each antenna branch. A data signal is output to the multiplexing means corresponding to the selected antenna branch, and the transmitting means transmits the frame from the corresponding antenna branch.

With these configurations, if the correlation value of the data signal at the reception timing of each common known signal is compared on the receiving side, the antenna branch from which the data signal was transmitted can be determined. By applying transmission diversity together, demodulation can be performed with high accuracy.

The CDMA communication apparatus of the present invention employs a configuration including a first spreading means for spreading a data signal with a first spreading code different for each channel and outputting the spread data signal to an antenna branch selecting means.

The CDMA communication apparatus according to the present invention employs a configuration in which the first spreading means spreads a data signal with a different first spreading code for each antenna branch.

With these configurations, even when a delay occurs due to transmission on different propagation paths, respective correlation values can be obtained without being affected by the delay. Therefore, by comparing these correlation values, The antenna branch used for transmission can be accurately determined.

The CDMA communication apparatus of the present invention includes second spreading means for multiplying a frame by a different second spreading code for each CDMA communication apparatus, and the transmitting means transmits the frame multiplied by the second spreading code. It adopts the configuration to do.

The CDMA communication apparatus according to the present invention employs a configuration in which the second spreading means spreads a frame with a different second spreading code for each antenna branch.

With these configurations, it is possible to prevent the orthogonality between signals transmitted from different antenna branches from being destroyed due to delay caused by different propagation paths. Can be distinguished.

The CDMA communication apparatus of the present invention employs a configuration in which the transmitting means transmits a signal at a different timing for each antenna branch.

According to this configuration, the delay profile of signals transmitted from different antenna branches can be distinguished from each other on the receiving side, so that the antenna branch used for transmission can be accurately determined.

According to the CDMA communication apparatus of the present invention, an antenna branch is selected for each data signal, a corresponding data signal is transmitted from the selected antenna branch, and a different apparatus that transmits a different common known signal from each antenna branch is wirelessly connected to the other apparatus. A communication apparatus for performing communication, comprising: a plurality of delay profile creating means for creating a delay profile by multiplying a received signal by a spreading code; and a path determining means for determining a propagation path of the received signal based on the plurality of delay profiles. And a demodulating means for demodulating the received signal based on the result of the judgment by the path judging means.

[0027] In the CDMA communication apparatus of the present invention, the path determination means includes a synchronization acquisition means for acquiring reception timing based on the delay profile, and a correlation value calculation for despreading the reception signal at the reception timing to calculate a correlation value. Means, and a selection means for selecting a reception timing at which the correlation value becomes maximum, and the demodulation means adopts a configuration for demodulating at the selected reception timing.

With these configurations, by comparing the correlation value of the data signal at the reception timing of each common known signal, it is possible to determine the antenna branch from which the data signal has been transmitted. And demodulation can be performed with high accuracy.

[0029] The CDMA communication apparatus of the present invention employs a configuration in which the correlation value calculation means despreads a received signal with a different first spreading code for each antenna branch of a communication partner.

According to this configuration, even when a delay occurs due to transmission through different propagation paths, respective correlation values can be obtained without being affected by the delay. The antenna branch used for can be accurately determined.

In the CDMA communication apparatus according to the present invention, the delay profile creating means creates a delay profile by multiplying the received signal by a different second spreading code for each antenna branch, and the correlation value calculating means is a second spreading code. A configuration is employed in which a received signal is despread with a code.

With this configuration, it is possible to prevent the orthogonality between signals transmitted from different antenna branches from being destroyed due to a delay caused by a different propagation path. Therefore, it is possible to distinguish received signals transmitted from different antenna branches. can do.

The CDMA communication apparatus according to the present invention employs a configuration in which the correlation value calculating means calculates a correlation value by performing Rake combining.

With this configuration, it is possible to calculate a correlation value by synthesizing a plurality of paths from the delay profile of the received common known signal, so that the difference between the obtained correlation values becomes large and demodulation at the wrong phase is performed. It is possible to prevent synchronization, and to perform more accurate synchronization acquisition.

The CDMA communication apparatus according to the present invention includes a plurality of path determination means and a plurality of demodulation means, and employs a configuration for demodulating a plurality of types of data.

With this configuration, it is possible to demodulate signals of a plurality of information channels when a common known signal is applied to selective transmission diversity.

The communication terminal device of the present invention employs a configuration including any one of the above CDMA communication devices. A base station device according to the present invention includes any one of the CDMA communication devices described above,
A configuration is employed in which wireless communication is performed simultaneously with a plurality of communication terminal devices.

According to this configuration, when a common known signal is applied to the selective transmission diversity, demodulation can be performed with high accuracy, so that high quality wireless communication can be performed.

According to the CDMA communication method of the present invention,
Select an antenna branch for each data signal, transmit the corresponding data signal from the selected antenna branch, transmit a different common known signal from each antenna branch, and multiply the received signal by a spreading code on the receiving side to delay A profile is created, a propagation path of the received signal is determined based on the plurality of delay profiles, and the received signal is demodulated based on a result of the determination by the path determination unit.

According to this method, the antenna branch on which the data signal is transmitted can be determined by comparing the correlation value of the data signal at the reception timing of each common known signal on the receiving side. By applying diversity together, demodulation can be performed with high accuracy.

[0041]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The gist of the present invention is that a transmitting side transmits different common known signals from each antenna branch, and a receiving side obtains a correlation value at each reception timing of each common known signal, and obtains a correlation value. Is to despread the received signal at the reception timing with the largest value or at a plurality of reception timings with relatively large correlation values.

(Embodiment 1) FIG. 1 is a block diagram showing a configuration on the transmitting side of a CDMA communication apparatus according to Embodiment 1 of the present invention. Hereinafter, an example in which the transmitting side is a base station and the receiving side is a communication terminal will be described. FIG. 1 illustrates a case where the number of antenna branches is two and the number of data channels to be transmitted is three.

In FIG. 1, a communication device 100 is a PLC
Spreading section 101, PLC spreading section 102, spreading section 103
-1 to 103-3 and a plurality of switching units 104-1 to 10-4
4 to 3, a multiplexing unit 105, a multiplexing unit 106, a scramble code multiplication unit 107, a scramble code multiplication unit 108, a radio transmission unit 109, a radio transmission unit 110,
It mainly comprises an antenna branch 111 and an antenna branch 112.

PLC spreading section 101 multiplies the common known signal by a common channelization code (hereinafter referred to as “CCp”) # 1 to perform spreading processing, and outputs the obtained midamble to multiplexing section 105. PLC diffusion unit 102
Performs a spreading process by multiplying the common known signal by CCd # 2 different from CCd # 1, and outputs the obtained midamble code to multiplexing section 105. Thus, PLC spreading section 101 and PLC spreading section 102 generate different midambles respectively.

Spreading sections 103-1 to 103-3 respectively provide different individual channelization codes (hereinafter referred to as "CCd") # for input user information # 1 to # 3.
Spreading processing is performed by multiplying by 1 to # 3, and the obtained spread signals are output to switching sections 104-1 to 104-3, respectively.

Switching sections 104-1 to 104-3 select antenna branches based on the propagation path information, and multiplex the spread signals output from spreading sections 103-1 to 103-3 corresponding to the selected antenna branch. Output to unit 105 or multiplexing unit 106.

Here, the propagation path information indicates information of an antenna branch that has received a signal with good reception quality among a plurality of antenna branches that have received a signal transmitted from a communication partner.

The multiplexing section 105 includes switching sections 104-1 to 104-1.
After multiplexing the spread signals outputted from
A frame is formed together with the midamble code output from spreading section 101 and scramble code multiplication section 107
Output to The multiplexing unit 106 includes switching units 104-1 to 104-1.
After multiplexing the spread signals outputted from
A frame is formed together with the midamble code output from spreading section 102 and scramble code multiplication section 108
Output to

[0049] Scramble code multiplication section 107 multiplies the user information portion of the frame output from multiplexing section 105 by a scramble code (hereinafter referred to as “SC”) # 1 and outputs the result to radio transmission section 109. The scramble code multiplication unit 108 multiplies the user information portion of the frame output from the multiplexing unit 106 by SC # 1, and
Output to 10 The scrambling code is a spreading code that differs for each base station.

Radio transmission section 109 performs digital-analog conversion processing and frequency conversion processing on the frame output from scramble code multiplication section 107, and outputs the obtained transmission signal to antenna branch 111. Wireless transmission unit 1
10 performs digital-to-analog conversion processing and frequency conversion processing on the frame output from the scramble code multiplication section 108, and converts the obtained transmission signal into an antenna branch 11
Output to 2.

The antenna branch 111 includes the radio transmission unit 1
09 is transmitted. The antenna branch 112 transmits the transmission signal output from the wireless transmission unit 110.

FIG. 2 shows a CD according to the first embodiment of the present invention.
FIG. 2 is a block diagram illustrating a configuration of a receiving side of the MA communication device.

In FIG. 2, a communication device 200 includes a storage unit 201, a delay profile creation unit 202, a delay profile creation unit 203, and a delay profile selection unit 20.
4 and a demodulation unit 205.

The delay profile selecting section 204 includes a path selecting section 211, a path selecting section 212, and a correlation calculating section 213.
, A correlation operation unit 214, a reception power averaging unit 215,
It comprises a reception power averaging section 216 and a selection section 217.

The storage unit 201 stores the frequency-converted and analog-to-digital converted reception signals, and stores the received signals in the delay profile generation unit 202, the delay profile generation unit 203, the correlation operation unit 213, the correlation operation unit 214, and the like.
And outputs it to the demodulation unit 205.

[0056] Delay profile creation section 202 creates a delay profile by multiplying the received signal output from storage section 201 by CCp # 1, and outputs this delay profile to path selection section 211. Delay profile creation unit 2
03 indicates that the received signal output from the storage unit 201 has CCp
A delay profile is created by multiplying by # 2, and this delay profile is output to the path selection unit 212.

The path selector 211 selects a path having the largest correlation value from the delay profiles output from the delay profile generator 202, and outputs the reception timing of this path to the correlation calculator 213 and the demodulator 205. I do.
The path selector 212 selects a path having the largest correlation value from the delay profiles output from the delay profile generator 203, and outputs the reception timing of this path to the correlation calculator 214 and the demodulator 205.

Correlation calculation section 213 codes CCd # 1 and CCd # d for the reception signal output from storage section 201 based on the reception timing output from path selection section 211.
A correlation value with C # 1 is calculated and output to reception power averaging section 215.

Correlation calculating section 214 performs CCd # 1 and SC # 1 on the reception signal output from storage section 201 based on the reception timing output from path selection section 212.
Is calculated and output to the received power averaging section 216.

The received power averaging section 215 is provided for the correlation operation section 2
13 is averaged in a plurality of symbol units, and the obtained average value is output to the selection unit 217. Received power averaging section 216 averages the correlation values output from correlation operation section 214 in units of a plurality of symbols, and outputs the obtained average value to selection section 217.

The selecting section 217 includes a reception power averaging section 215
Is compared with the average value output from received power averaging section 216, and instruction information for selecting a received signal on a propagation path having a large power value is output to demodulation section 205.

The demodulation unit 205 selects one of the reception timings output from the path selection unit 211 or the path selection unit 212 according to the instruction information output from the selection unit 217, and outputs from the storage unit 201 at the selected reception timing. The demodulated received signal is demodulated.

Next, a communication frame transmitted and received by the communication device of the present invention will be described. FIG. 3 is a diagram illustrating an example of a communication frame according to the present embodiment.

FIG. 3A shows that the common known signal is represented by CCp # 1.
FIG. 9 is a diagram showing a frame including a symbol sequence multiplied by CCd # 2, a symbol sequence multiplied by data # 2 by CCd # 2, and a symbol sequence multiplied by CCd # 3 by data # 3. FIG. 3B is a diagram showing a frame including a symbol sequence obtained by multiplying the common known signal by CCp # 2 and a symbol sequence obtained by multiplying data # 1 by CCd # 1.

The common known signal is transmitted to the PLC
The LC spreading section 102 multiplies CCp # 1 and CCp # 2 respectively to generate midamble codes PLC # 1 and PLC # 2, and PLC # 1 and PLC # 2
Multiplexed with the data subjected to spread processing in the multiplexing unit, and FIG.
3A and 3B, and are output from the antenna branch 111 or the antenna branch 112.

The user information # 1 to # 3 are multiplied by different individual channelization codes (hereinafter referred to as "CCd") # 1 to # 3 in the spreading sections 103-1 to 103-3, respectively, to obtain DT #. 1 to # 3 are generated.

FIG. 3C is a diagram showing a frame received by the communication device 200. Antenna branch 1
Since the signal output from the antenna branch 11 or the antenna branch 112 is delayed and attenuated due to the difference in the propagation path, it is necessary to individually determine the reception timing of the signal transmitted from a plurality of antenna branches in one midamble on the receiving side. Can not.

Communication apparatus 200 uses different codes CCp #
1 and CCp # 2 to despread the received signal to determine the reception timing of the received signal transmitted through a plurality of propagation paths, compare the despread correlation values at these reception timings, and determine the propagation path having a large correlation value. The received signal is demodulated at the reception timing.

FIG. 3D is a diagram showing an example of a delay profile obtained by despreading the received signal by CCp # 1 and CCp # 2 in communication apparatus 200.

As shown in FIG. 3D, the delay profile P1 and the delay profile P2 have different reception timings and different correlation values due to different propagation paths. Although not shown in the figure, the phases are different.

As described above, the communication device 200
By obtaining the correlation value of the frame (c) with two different midamble codes CCp # 1 and CCp # 2, a reception timing for performing despreading with a signal transmitted through two propagation paths is obtained. At these reception timings, the user information portion of the received signal is despread to obtain a correlation value, it is determined that the signal has been transmitted from a propagation path having a large correlation value, and the received signal is demodulated at the reception timing.

As described above, according to the CDMA communication apparatus of the present embodiment, different common known signals are transmitted from each antenna branch, and the reception side compares the correlation value of the data signal at the reception timing of each common known signal. By doing so, the antenna branch from which the data signal has been transmitted can be determined, so that both the common common known signal and the selected transmission diversity can be applied, and demodulation can be accurately performed.

The above example shows an example in which the transmitting side is a base station and the receiving side is a communication terminal. However, the present invention is not limited to this, and the present invention can be applied to a case where the transmitting side is a communication terminal and the receiving side is a base station. . In this case, the receiving side of the CDMA communication apparatus according to the present embodiment demodulates signals of a plurality of information channels.

An example of demodulating signals of three information channels will be described below. FIG. 4 is a diagram illustrating an example of the CDMA communication apparatus according to the present embodiment that demodulates signals of a plurality of information channels.

In FIG. 4, a delay profile creation unit 2
02 indicates that the received signal output from the storage unit 201 has CCp
# 1 is multiplied to create a delay profile, and this delay profile is used as a delay profile selection unit 204-1 to 20-20.
Output to 4-3. The delay profile creation unit 203
The received signal output from storage section 201 is multiplied by CCp # 2 to create a delay profile, and this delay profile is output to delay profile selection sections 204-1 to 204-3.

Delay profile selection units 204-1 to 20-20
4-3, a path having the maximum correlation value is selected from the delay profiles output from the delay profile generation unit 202 and the delay profile generation unit 203, and CCd # 1 to CCd # 3 are respectively multiplied at the reception timing of this path. Then, despreading is performed to calculate a correlation value. Further, delay profile selection sections 204-1 to 204-3 output reception timing information of this path to demodulation sections 205-1 to 205-3.

Then, the delay profile selecting section 204-
Reference numerals 1 to 204-3 compare the obtained correlation values and output instruction information for selecting a reception signal of a propagation path having a large value to the demodulation unit 2.
05-1 to 205-3.

The demodulation sections 205-1 to 205-3 use the reception timing information output from the delay profile selection sections 204-1 to 204-3 to add CCd # 1 to the reception signal.
To CCd # 3 to perform despreading processing and output the obtained user information # 1 to # 3.

As described above, the CDMA communication apparatus according to the present embodiment can demodulate signals of a plurality of information channels.

(Embodiment 2) FIG. 5 is a block diagram showing an example of a configuration on the receiving side of a CDMA communication apparatus according to Embodiment 2. However, the configuration common to FIG.
The same reference numerals as in the first embodiment denote the same parts, and a detailed description thereof will be omitted.

The CDMA communication apparatus 300 shown in FIG.
It differs from FIG. 2 in that it includes an E combining unit 311 and a RAKE combining unit 312, performs RAKE combining on the received signal, and compares the obtained correlation values to determine the antenna branch from which the received signal was transmitted. .

In FIG. 5, delay profile selecting section 3
01 is a path selection unit 211, a path selection unit 212, and R
It comprises an AKE combining section 311, a RAKE combining section 312, a received power averaging section 215, a received power averaging section 216, and a selecting section 217.

The path selector 211 selects a path having the maximum correlation value from the delay profile output from the delay profile generator 202, and outputs the reception timing of this path to the RAKE combiner 311 and the demodulator 205.
The path selection unit 212 selects a path having the largest correlation value from the delay profile output from the delay profile creation unit 203, and outputs the reception timing of this path to the RAKE combining unit 312 and the demodulation unit 205.

The RAKE synthesizing unit 311
Storage unit 20 based on the reception timing output from
A plurality of paths are combined for the received signal output from No. 1 to calculate a correlation value and output to the received power averaging section 215.

The RAKE synthesizing unit 312
Storage unit 20 based on the reception timing output from
A plurality of paths are combined with respect to the received signal output from No. 1 to calculate a correlation value and output to the received power averaging section 216.

[0086] Received power averaging section 215 averages the correlation value output from RAKE combining section 311 in units of a plurality of symbols, and outputs the obtained average value to selecting section 217. Received power averaging section 216 includes RAKE combining section 312
Are averaged in units of a plurality of symbols, and the obtained average value is output to the selection unit 217.

As described above, according to the CDMA communication apparatus of the present embodiment, different common known signals are transmitted for each antenna branch, and the reception side compares the correlation value between the received signal and each common known signal. By judging the antenna branch transmitted for each individual channel, demodulation can be accurately performed when a common known signal is applied to selected transmission diversity.

Further, by calculating a correlation value by combining a plurality of paths from the delay profile of the received common known signal, it is possible to prevent the difference between the obtained correlation values from increasing and to prevent demodulation at an erroneous phase. Therefore, more accurate synchronization acquisition can be performed as compared with the first embodiment.

The CDMA communication apparatus according to the present embodiment can also demodulate signals of a plurality of information channels. In this case, a plurality of delay profile selection units 301
And a plurality of demodulation sections 205, and calculates and demodulates the reception timing for each user information to realize the demodulation.

(Embodiment 3) FIG. 6 is a block diagram showing a configuration on the transmitting side of a CDMA communication apparatus according to Embodiment 3 of the present invention. However, components having the same configuration as in FIG. 1 are assigned the same reference numerals as in FIG. 1, and detailed description is omitted.

The CDMA communication apparatus 600 of FIG. 6 includes switching sections 601-1 to 601-3 and multiplies the user information by a different code for each antenna branch.
And different.

In FIG. 6, switching section 601-1 selects a spreading code corresponding to an antenna branch to be transmitted on a propagation path in good condition based on propagation path information, and outputs user information # 1 from antenna branch 111. If
When CCd # 11 is selected and user information # 1 is output from antenna branch 112, CCd # 12 is selected and output to spreading section 103-1.

Similarly, switching section 601-2 selects CCd # 21 or CCd # 22 based on the propagation path information and outputs it to spreading section 103-2. Similarly, the switching unit 601
-3 is CCd # 31 or Cd # 31 based on the propagation path information.
Cd # 32 is selected and output to spreading section 103-3.

Spreading section 103-1 converts input user information # 1 into CCd # output from switching section 601-1.
11 or CCd # 12 to perform spreading processing, and outputs the obtained spread signal to switching section 104-1.

Similarly, spreading section 103-2 outputs CCd # 2 output from switching section 601-2 to user information # 2.
The spread signal obtained by multiplying by 1 or CCd # 22 is output to switching section 104-3. Diffusion unit 103-
3 outputs a spread signal obtained by multiplying user information # 3 by CCd # 31 or CCd # 32 output from switching section 601-3 to switching section 104-3.

FIG. 7 shows a CD according to the third embodiment of the present invention.
FIG. 2 is a block diagram illustrating a configuration of a receiving side of the MA communication device.
However, components having the same configuration as in FIG. 2 are assigned the same reference numerals as in FIG. 2 and detailed description thereof is omitted.

The CDMA communication apparatus 700 shown in FIG. 7 includes a delay profile selecting section 701 and a demodulating section 702.
The difference from FIG. 2 is that the received signal is demodulated with a different spreading code for each transmitted antenna branch and the obtained correlation values are compared.

In FIG. 7, a delay profile selection unit 7
01 is a path selection unit 211, a path selection unit 212, a correlation operation unit 711, a correlation operation unit 712, a reception power averaging unit 215, a reception power averaging unit 216, and a selection unit 21.
And 7.

The path selector 211 selects a path having the largest correlation value from the delay profiles output from the delay profile generator 202, and outputs the reception timing of this path to the correlation calculator 711. Path selection unit 212
Selects the path having the largest correlation value from among the delay profiles output from the delay profile creation unit 203, and outputs the reception timing of this path to the correlation calculation unit 712.

Correlation calculating section 711 performs CCd # 11 and SC # 1 on the reception signal output from storage section 201 based on the reception timing output from path selection section 211.
Is calculated and output to the received power averaging section 215.

Correlation calculating section 712 performs CCd # 12 and SC # 1 on the reception signal output from storage section 201 based on the reception timing output from path selection section 212.
Is calculated and output to the received power averaging section 216.

The reception power averaging section 215
The correlation value output from 11 is averaged in units of a plurality of symbols, and the obtained average value is output to the selection unit 217.
Received power averaging section 216 averages the correlation value output from correlation operation section 712 in units of a plurality of symbols, and outputs the obtained average value to selection section 217.

The selecting section 217 includes a reception power averaging section 215
Is compared with the average power value output from received power averaging section 216, and outputs to demodulation section 702 instruction information for selecting a received signal on a propagation path having a large power value. Demodulation section 702 demodulates the received signal output from storage section 201 according to the instruction information output from selection section 217.

As described above, according to the CDMA communication apparatus of the present embodiment, the transmitting side transmits different common known signals for each antenna branch, and the receiving side calculates the correlation value between the received signal and each common known signal. By comparing and determining the antenna branch transmitted for each individual channel, it is possible to apply both the common known signal and the selected transmission diversity.

Further, according to the CDMA communication apparatus of the present embodiment, even when a delay occurs due to transmission on a different propagation path, a received signal is despread with a different spreading code for each antenna branch. Since each correlation value can be obtained without being affected by the delay, the antenna branch used for transmission can be accurately determined by comparing the correlation values.

The CDMA communication apparatus according to the present embodiment can also use Rake combining for despreading of a received signal. In this case, the correlation operation unit 213 and the correlation operation unit 21
4 can be realized by replacing the RAKE combining unit 311 and the RAKE combining unit 312 as in the second embodiment.

The CDMA communication apparatus according to the present embodiment can also demodulate signals of a plurality of information channels. In this case, a plurality of delay profile selection units 701
And a plurality of demodulation units 702, and calculates and demodulates the reception timing for each user information to be realized.

(Embodiment 4) FIG. 8 is a block diagram showing a configuration on the transmitting side of a CDMA communication apparatus according to Embodiment 4 of the present invention. However, components having the same configuration as in FIG. 1 are assigned the same reference numerals as in FIG. 1, and detailed description is omitted.

The CDMA communication apparatus 800 shown in FIG. 8 includes a scramble code multiplication unit 801 and a scramble code multiplication unit 802, and uses a different code for each antenna branch as a scramble code, and multiplies a common known signal and transmission data. 1 is different from FIG.

In FIG. 8, multiplexing section 105 multiplexes spread signals output from switching sections 104-1 to 104-3, and then forms a frame together with a midamble code output from PLC spreading section 101 to scramble. Output to the code multiplication unit 801. The multiplexing unit 106 multiplexes the spread signals output from the switching units 104-1 to 104-3, forms a frame together with the midamble code output from the PLC spreading unit 102, and outputs the frame to the scramble code multiplication unit 802. .

[0111] Scramble code multiplying section 801 multiplies the user information portion of the frame output from multiplexing section 105 by SC # 1, and outputs the result to radio transmitting section 109. Scramble code multiplying section 802 multiplies the user information portion of the frame output from multiplexing section 106 by SC # 2 and outputs the result to radio transmitting section 110.

Radio transmission section 109 performs digital-analog conversion processing and frequency conversion processing on the frame output from scramble code multiplication section 801, and outputs the obtained transmission signal to antenna branch 111. Wireless transmission unit 1
10 performs digital-to-analog conversion processing and frequency conversion processing on the frame output from the scramble code multiplication section 802, and converts the obtained transmission signal into an antenna branch 11
Output to 2.

FIG. 9 shows a CD according to the fourth embodiment of the present invention.
FIG. 2 is a block diagram illustrating a configuration of a receiving side of the MA communication device.
However, components having the same configuration as in FIG. 2 are assigned the same reference numerals as in FIG. 2 and detailed description thereof is omitted.

A CDMA communication apparatus 900 shown in FIG. 9 includes a delay profile creation section 901 and a delay profile creation section 9.
02, a delay profile selection unit 903, and a demodulation unit 90
2 is different from FIG. 2 in that a different code is used for each antenna branch as a scramble code, and a reception timing is calculated from a correlation value obtained by multiplying the received signal by this code.

The delay profile selecting section 903 includes a path selecting section 211, a path selecting section 212, and a correlation calculating section 911.
, A correlation calculator 912, a received power averaging unit 215,
It comprises a reception power averaging section 216 and a selection section 217.

The storage unit 201 stores the received signal subjected to the frequency conversion and the analog-to-digital conversion, and stores the stored received signal in a delay profile creation unit 901, a delay profile creation unit 902, a correlation operation unit 911, a correlation operation unit 912,
And output to the demodulation unit 904.

The delay profile creation section 901 creates a delay profile by multiplying the received signal output from the storage section 201 by CCp # 1, and outputs this delay profile to the path selection section 211. Delay profile creation unit 9
02 multiplies the received signal output from the storage unit 201 by the code CCp # 2 to create a delay profile, and outputs this delay profile to the path selection unit 212.

The path selector 211 selects a path having the largest correlation value from the delay profiles output from the delay profile generator 901, and outputs the reception timing of this path to the correlation calculator 911 and the demodulator 904. I do.
The path selector 212 selects a path having the largest correlation value from the delay profiles output from the delay profile generator 902, and outputs the reception timing of this path to the correlation calculator 912 and the demodulator 904.

Correlation calculating section 911 performs CCd # 1 and SC # 1 on the reception signal output from storage section 201 based on the reception timing output from path selection section 211.
Is calculated and output to the received power averaging section 215.

[0120] Correlation calculating section 912 performs CCd # 1 and SC # 2 on the reception signal output from storage section 201 based on the reception timing output from path selection section 212.
Is calculated and output to the received power averaging section 216.

The received power averaging section 215 is provided for the correlation operation section 9.
The correlation value output from 11 is averaged in units of a plurality of symbols, and the obtained average value is output to the selection unit 217.
Received power averaging section 216 averages the correlation value output from correlation operation section 912 in units of a plurality of symbols, and outputs the obtained average value to selection section 217.

Selection section 217 includes reception power averaging section 215
Is compared with the average power value output from received power averaging section 216, and outputs to demodulation section 904 instruction information for selecting a received signal on a propagation path having a large power value. Demodulation section 904 selects and uses SC # 1 or SC # 2 according to the instruction information output from selection section 217, and demodulates the received signal output from storage section 201.

As described above, according to the CDMA communication apparatus of the present embodiment, the transmitting side transmits a different common known signal for each antenna branch, and the receiving side calculates the correlation value between the received signal and each common known signal. By comparing and judging the antenna branch transmitted for each individual channel, demodulation can be accurately performed when a common known signal is applied to selected transmission diversity.

Further, by multiplying a frame with a different scrambling code for each antenna branch, it is possible to prevent the orthogonality between signals transmitted from different antenna branches from being broken due to a delay caused by a different propagation path. As a result, the received signals transmitted from different antenna branches can be distinguished.

Note that the CDMA communication apparatus according to the present embodiment can use Rake combining for despreading of a received signal. In this case, the correlation operation unit 213 and the correlation operation unit 21
4 can be realized by replacing the RAKE combining unit 311 and the RAKE combining unit 312 as in the second embodiment.

The CDMA communication apparatus according to the present embodiment can also demodulate signals of a plurality of information channels. In this case, a plurality of delay profile selection units 903
And a plurality of demodulators 904, and calculates and demodulates the reception timing for each user information to realize the demodulation.

(Embodiment 5) FIG.10 is a block diagram showing a configuration on the transmitting side of a CDMA communication apparatus according to Embodiment 5 of the present invention. However, components having the same configuration as in FIG. 1 are assigned the same reference numerals as in FIG. 1, and detailed description is omitted.

The CDMA communication apparatus 1000 shown in FIG. 10 includes a delay unit 1001 and a delay unit 1002 and transmits signals at different timings for each antenna branch.
Different from FIG.

In FIG. 10, scramble code multiplying section 107 multiplies the user information portion of the frame output from multiplexing section 105 by SC # 1 and outputs the result to delay section 1001. The scramble code multiplication unit 108 adds S to the user information portion of the frame output from the multiplexing unit 106.
C # 1 is multiplied and output to delay section 1002.

[0130] Delay section 1001 delays the frame output from scramble code multiplication section 107 by a predetermined time, and outputs the result to radio transmission section 109. Delay unit 1002
Delays the frame output from scramble code multiplication section 108 by a predetermined time, and outputs the result to radio transmission section 110. The delay unit 1001 and the delay unit 1002 output frames with a delay time set such that the timings of the output frames are output with a predetermined time difference from each other.

Radio transmitting section 109 performs digital-to-analog conversion processing and frequency conversion processing on the frame output from delay section 1001, and outputs the obtained transmission signal to antenna branch 111. The wireless transmission unit 110 includes the delay unit 1
A digital-to-analog conversion process and a frequency conversion process are performed on the frame output from 002, and the obtained transmission signal is output to the antenna branch 112.

FIG. 11 is a diagram showing an example of a delay profile of a signal transmitted from two antenna branches.
In FIG. 11, the vertical axis indicates the level of the correlation value, and the horizontal axis indicates the time. The delay profile P11 indicates a delay profile of a signal output from the antenna branch 111. The delay profile P12 indicates a delay profile of a signal output from the antenna branch 112.

Two delay profiles P11 and P12
Are transmitted with a predetermined time difference, so that the peak of the delay profile can be separated and distinguished at the time of reception.

As described above, according to the CDMA communication apparatus of the present embodiment, the transmitting side transmits different common known signals for each antenna branch, and the receiving side calculates the correlation value between the received signal and each common known signal. By comparing and judging the antenna branch transmitted for each individual channel, demodulation can be accurately performed when a common known signal is applied to selected transmission diversity.

Also, by giving a time difference to a transmitted frame, it is possible to distinguish delay profiles of signals transmitted from different antenna branches on the receiving side, so that the antenna branch used for transmission is determined. Can be.

The delay unit 1001 or the delay unit 100
2 to provide a time difference between signals to be transmitted.

Although the first to fifth embodiments have been described using two antenna branches and three pieces of user information as examples, the CDMA communication apparatus of the present invention is not limited to this.
It can be applied to multiple antenna branches. In this case, the present invention can be applied by spreading a common known signal using different spreading codes by the number of antenna branches.

The number of pieces of user information is not limited to this, but can be applied if there is a plurality. In this case, the present invention can be applied by spreading user information by using spreading codes different by the number of users.

[0139]

As described above, the CDMA of the present invention
According to the communication apparatus and the CDMA communication method, the transmitting side transmits different common known signals from each antenna branch, and the receiving side obtains a correlation value at the reception timing of each common known signal, and the correlation value is the largest. By despreading the received signal at the reception timing, it is possible to accurately demodulate when the common known signal is applied to the selected transmission diversity.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration on a transmitting side of a CDMA communication apparatus according to Embodiment 1 of the present invention.

FIG. 2 is a block diagram showing a configuration on a receiving side of the CDMA communication apparatus according to Embodiment 1 of the present invention.

FIG. 3 is a diagram illustrating an example of a communication frame according to the present embodiment;

FIG. 4 is a diagram showing an example of a CDMA communication apparatus according to the present embodiment for demodulating signals of a plurality of information channels.

FIG. 5 is a block diagram showing an example of a configuration on the receiving side of the CDMA communication apparatus according to Embodiment 2.

FIG. 6 is a block diagram showing a configuration on a transmitting side of a CDMA communication apparatus according to Embodiment 3 of the present invention.

FIG. 7 is a block diagram showing a configuration of a receiving side of a CDMA communication apparatus according to Embodiment 3 of the present invention.

FIG. 8 is a block diagram showing a configuration on the transmitting side of a CDMA communication apparatus according to Embodiment 4 of the present invention.

FIG. 9 is a block diagram showing a configuration on a receiving side of a CDMA communication apparatus according to Embodiment 4 of the present invention.

FIG. 10 is a block diagram showing a configuration on a transmitting side of a CDMA communication apparatus according to Embodiment 5 of the present invention.

FIG. 11 is a diagram illustrating an example of a delay profile of a signal transmitted from two antenna branches.

FIG. 12 is a schematic diagram showing a procedure for creating a midamble in a CDMA wireless communication system;

[Explanation of symbols]

101, 102 PLC spreading sections 103-1 to 103-3 Spreading sections 104-1 to 104-3, 601 Switching sections 105, 106 Multiplexing sections 107, 108, 801, 802 Scramble code multiplying sections 109, 110 Radio transmitting sections 111, 112 antenna branch 201 storage unit 202, 203, 901, 902 delay profile creation unit 204, 204-1 to 204-3, 301, 701, 9
03 Delay profile selection unit 205, 205-1 to 205-3, 702, 904 Demodulation unit 211, 212 Path selection unit 213, 214, 711, 712, 911, 912 Correlation calculation unit 215, 216 Received power averaging unit 217 selection Units 311 and 312 RAKE combining units 1001 and 1002 delay units

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H04M 1/725 H04J 13/00 D

Claims (17)

[Claims] A plurality of antenna branches; an antenna branch selecting means for selecting an optimum antenna branch for transmitting a data signal in accordance with a propagation path condition for each data signal; Transmitting means for transmitting and transmitting a different common known signal for each antenna branch.
A communication device. 2. A data signal and a common known signal are time-multiplexed for each antenna branch, and the same number of multiplexing means as the number of said antenna branches forming a frame are provided. The antenna branch selecting means corresponds to the selected antenna branch. The CDMA communication apparatus according to claim 1, wherein a data signal is output to the multiplexing unit, and the transmitting unit transmits the frame from a corresponding antenna branch. 3. The CDMA according to claim 1, further comprising first spreading means for spreading a data signal with a first spreading code different for each channel and outputting the spread signal to an antenna branch selecting means. Communication device. 4. The CDMA communication apparatus according to claim 3, wherein the first spreading means spreads the data signal with a different first spreading code for each antenna branch. 5. A second spreading means for multiplying a frame by a different second spreading code for each CDMA communication device, wherein the transmitting means transmits the frame multiplied by the second spreading code. The CDMA communication device according to claim 1. 6. The CDMA communication apparatus according to claim 5, wherein the second spreading means spreads the frame with a different second spreading code for each antenna branch. 7. The CDMA communication apparatus according to claim 1, wherein the transmitting unit transmits a signal at a different timing for each antenna branch. 8. A communication device for selecting an antenna branch for each data signal, transmitting a corresponding data signal from the selected antenna branch, and performing wireless communication with a partner device transmitting a different common known signal from each antenna branch. A plurality of delay profile creating means for creating a delay profile by multiplying a received signal by a spreading code; a path determining means for determining a propagation path of the received signal based on the plurality of delay profiles; And a demodulating means for demodulating the received signal based on the result of the determination. 9. A path determination unit, comprising: a synchronization acquisition unit for acquiring a reception timing based on a delay profile; a correlation value calculation unit for despreading a reception signal at the reception timing to calculate a correlation value; 9. The CDMA communication apparatus according to claim 8, further comprising: selecting means for selecting a reception timing at which the maximum is obtained, wherein the demodulation means demodulates at the selected reception timing. 10. The CDMA communication apparatus according to claim 9, wherein the correlation value calculating means despreads the received signal with a different first spreading code for each antenna branch of a communication partner. 11. A delay profile creation means for multiplying a received signal by a different second spreading code for each antenna branch to create a delay profile, and a correlation value calculating means inversely inverses the received signal with the second spreading code. The CDMA communication device according to claim 9 or 10, wherein spreading is performed. 12. The CDMA communication apparatus according to claim 9, wherein the correlation value calculating means calculates a correlation value by performing Rake combining. 13. The CDM according to claim 8, further comprising a plurality of path determination means and a plurality of demodulation means for demodulating a plurality of types of data.
A communication device. 14. A communication terminal device comprising the CDMA communication device according to claim 1. Description: 15. A base station apparatus comprising the CDMA communication apparatus according to claim 1 and performing wireless communication simultaneously with a plurality of communication terminal apparatuses. 16. A base station apparatus comprising the CDMA communication apparatus according to claim 13, and performing wireless communication simultaneously with a plurality of communication terminal apparatuses. 17. A transmitting side selects an antenna branch for each data signal, transmits a corresponding data signal from the selected antenna branch, transmits a different common known signal from each antenna branch, and Multiplying the signal by a spreading code to create a delay profile, determining a propagation path of the received signal based on the plurality of delay profiles, and demodulating the received signal based on a result of the determination by the path determining means. CDMA communication method.