JPH11225094A - Spread spectrum communication receiver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a spread spectrum receiver by which an error in demodulated data is reduced even when an estimated interference signal differs from an actual interference signal. SOLUTION: The receiver is provided with a plurality of systems, corresponding to plural spread codes, each consisting of an inverse spread means, a propagation path estimate means 1-9 that estimate an amplitude/phase characteristic of a propagation path, a diversity synthesis means 1-2 that uses the estimated result to conduct diversity synthesis of an inverse spread signal, a decoding means 1-3 for an output signal, an interference recovery means 1-4 which use a decoding means output and a propagation path estimate means output of a system corresponding to other spread code to estimate an interference signal to the spread code system, a multiplier 1-10, a delay means, a subtractor means 1-6 that subtracts an output signal of the multiplier means from the output of the delay means to eliminate interference, a diversity synthesis means 1-7 that uses an estimate result by the propagation path estimate means to conduct diversity synthesis of the output signal of the subtractor means and a decoding means 1-8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a receiver for spread spectrum communication which receives a plurality of signals spread by a plurality of different spread codes, and more particularly to a receiver for spread spectrum communication capable of reducing errors in demodulated data. Related to a receiving device.

[0002]

2. Description of the Related Art In a receiver for spread spectrum communication, there is a method of estimating an interference signal from a propagation path characteristic to be estimated and a demodulated signal and removing the interference signal to reduce errors in demodulated data. This method includes a method of reproducing an interference signal before despreading and removing the interference signal from a received signal before despreading to demodulate data, and a method of demodulating data before despreading in order to further reduce errors in demodulated data. There is a method of demodulating data by regenerating an interference signal and multiplying the signal by a coefficient to remove the signal from a received signal before despreading.

However, in this conventional method, interference reproduction and interference removal are performed on a signal before despreading, so that high-speed signal processing is required, re-spreading means for interference reproduction and data There is a problem that despreading means for demodulation is required. On the other hand, there is also a method of reproducing the despread interference signal, removing this from the despread received signal, and demodulating the data. Hereinafter, this method will be described.

FIG. 4 is a diagram showing an example of the configuration of a conventional receiver for spread spectrum communication.
-1, 3-1 are passive correlators, 1-2, 2-2, 3-2,
1-7, 2-7, 3-7 are diversity combiners, 1-
3, 2-3, 3-3 are decoders, 1-4, 2-4, 3-4
Is an interference regenerator, 1-5, 2-5, 3-5 are delay units, 1-
6, 2-6, 3-6 are adders, 1-8, 2-8, 3-8
Is a decoder, 1-9, 2-9, 3-9 are propagation path estimators, 4
Represents an input terminal, and 5-1 to 5-3 represent output terminals. The numbers in the circles are different from the signals, and the input and output relationships are indicated by arrows, and the output signals are applied to the input side having the same number.

In FIG. 4, three signals, each of which has been spread with different spreading codes, are received through different propagation paths, and the received baseband signals, which are quasi-coherently detected together, are spread in respective transmission channels. The signals are input to the passive correlator 1-1, the passive correlator 2-1 and the passive correlator 3-1 matching the code, and the correlation values are output from these. The output signal of the passive correlator 1-1 is diversity-combined by the diversity combiner 1-2 using the amplitude / phase characteristics of the propagation path obtained from the propagation path estimator 1-9. Data of the output signal 2 is decoded by the decoder 1-3. The passive correlator 2-
1 or the respective systems including the passive correlator 3-1 perform the same operation.

The passive correlator 1-1 and the passive correlator 2-
1 and the output signal of the passive correlator 3-1
-5, the delay unit 2-5, and the delay unit 3-5.
The delay unit 1-5 delays the input signal to adjust the addition timing in the adder 1-6. In the interference regenerator 1-4, a decoder 2-3 of another sequence, a channel estimator 2-9, and a decoder 3-
3. Estimate the interference signal using the signal obtained from the propagation path estimator 3-9, and remove the interference signal from the output signal of the passive correlator 1-1 containing the interference signal in the adder 1-6. I do.

The output signal of the adder 1-6 is diversity-combined in the diversity combiner 1-7 using the amplitude and phase of the propagation path obtained from the propagation path estimator 1-9. The output signal of 7 is decoded by the decoder 1-8 and output from the output terminal 5-1. The operation in each system including the delay unit 2-5 or the delay unit 3-5 is the same, and the data is decoded by the decoder 2-8 and the decoder 3-8, respectively, and the output terminal 5-2 or Output from 5-3.

[0008]

The conventional method described above has a problem that when the estimated interference signal is different from the actual interference signal, errors in demodulated data are likely to increase. The present invention is intended to realize a receiver for spread spectrum communication that can solve such a conventional problem, even if the estimated interference signal is different from the actual interference signal, It is an object of the present invention to provide a receiver for spread spectrum communication capable of reducing the influence of demodulated data on demodulated data and reducing errors in demodulated data as compared with the related art.

[0009]

According to the present invention, the above-mentioned object is solved by the means described in the claims. That is, the invention of claim 1 is a receiving apparatus for spread spectrum communication for receiving a plurality of signals spread spectrum by a plurality of different spreading codes, and a despreading means for outputting a despread signal corresponding to the spreading code. A channel estimation means for estimating the amplitude and phase characteristics of the channel,

A first diversity combining means for performing diversity combining of the despread signal using the estimation result of the propagation path estimating means; and a first decoding means for decoding an output signal of the first diversity combining means. An interference reproducing means for estimating an interference signal to the spreading code system using a decoding means output and a propagation path estimating means output of a system corresponding to another spreading code, and reproducing the interference signals, Multiplying means for multiplying an output signal by a coefficient, delay means for delaying an output signal of the despreading means,

A subtractor for subtracting the output signal of the multiplying means from the output of the delay means to remove interference; and a second means for performing diversity synthesis of the output signal of the subtractor using the estimation result of the propagation path estimating means. A spread spectrum communication receiving apparatus in which a system having a diversity combining means and a second decoding means for decoding an output signal of the second diversity combining means is provided in a plurality of sequences corresponding to the plurality of different spreading codes. It is.

According to a second aspect of the present invention, in the receiver for spread spectrum communication according to the first aspect, a propagation path estimating means is provided in common for a plurality of spread code systems received via the same propagation path. , The interference regenerators of the respective streams commonly use the output of the channel estimation means.

According to a third aspect of the present invention, in the spread spectrum communication receiver according to the first or second aspect, another delay means for delaying an output signal of the preceding delay means and another series of delay means, Using the output of the combining means corresponding to the preceding stage and the output of the propagation path estimating means of another sequence, estimating an interference signal to the spreading code system, and regenerating interference signals, Another multiplication means for multiplying the output signal of the reproduction means by a coefficient, and another subtraction means for subtracting the output signal of the multiplication means from the output of the delay means to remove interference,

Another diversity combining means for performing diversity combining of the output signal of the subtracting means using the estimation result of the propagation path estimating means, and another decoding means for decoding the output signal of the other diversity combining means. At least one circuit block is provided between at least one series of delay means and subtraction means.

The configuration of the present invention differs from the prior art in that it has means for multiplying the output signal of the reproducing means for reproducing the despread interference signal by a coefficient.

[0016]

According to the present invention, the effect on demodulated data obtained from the second decoding means when the estimated interference signal is different from the actual interference signal is reduced by multiplying the output signal of the interference reproduction means by a coefficient. So that
It is possible to reduce errors in demodulated data obtained from the second decoding means.

The value of the coefficient is equal to or greater than 0 in order to remove the estimated interference signal, and the output of the channel estimating means corresponding to another spreading code is accurate, and If there is no error in the output signal of the first decoding means, the magnitude of the reproduced interference signal must be less than 1 so as not to exceed the actual interference signal. The conventional method corresponds to the case where the coefficient in the present invention is 1, and does not consider the case where the output signal of the first composite means corresponding to another spreading code is erroneous. Is added, the error of the demodulated data obtained from the second decoding means is increased.

If the coefficient is less than 1, if there is no error in the output signal of the first decoding means corresponding to another spreading code,
A part of the interference signal remains without being removed, slightly increasing the error of the demodulated data obtained from the second decoding means, but the output signal of the first decoding means corresponding to another spreading code is erroneous. In this case, since a part of the reproduced interference signal is added, the error of the demodulated data obtained from the second decoding means can be reduced, and as a result, the error of the overall demodulated data can be reduced. it can. .

[0019]

FIG. 1 shows a first embodiment of the present invention.
It is a figure showing the example of. In FIG.
0, 2-10, and 3-10 represent multipliers. Other numerals and numerals in circles are the same as those in FIG. 4 described above. In FIG. 1, three signals modulated by different spreading codes are respectively received through different propagation paths, and a received baseband signal, which is quasi-coherently detected together, is spread from an input terminal 4 to spread each transmission channel. The passive correlator 1-1, the passive correlator 2-1 and the passive correlator 3-1 matching the code are input to the passive correlator 1-1, and the correlation value is output from each passive correlator.

The output signal of the passive correlator 1-1 is diversity-combined by the diversity combiner 1-2 using the amplitude and phase of the propagation path obtained from the propagation path estimator 1-9. The data of the output signal of -2 is decoded by the decoder 1-3.

Similarly, the output signal of the passive correlator 2-1 is
Diversity combining is performed by the diversity combiner 2-2 using the amplitude and phase of the propagation path obtained from the propagation path estimator 2-9, and the output signal of the diversity combiner 2-2 is decoded by the decoder 2-3. Decrypted. Similarly, the output signal of the passive correlator 3-1 is output to the propagation path estimator 3-9.
Diversity combining is performed by the diversity combiner 3-2 using the obtained amplitude and phase of the propagation path, and the output signal of the diversity combiner 3-2 is decoded by the decoder 3-3.

The passive correlator 1-1 and the passive correlator 2-
1 and the output signal of the passive correlator 3-1
-5, input to the delay unit 2-5 and the delay unit 3-5. The delay unit 1-5 delays the input signal to adjust the addition timing in the adder 1-6. The interference regenerator 1-4 estimates an interference signal using the signals obtained from the decoder 2-3, the propagation path estimator 2-9, the decoder 3-3, and the propagation path estimator 3-9.

The output signal of the interference regenerator 1-4 is multiplied by a coefficient r (0 <r <1) by a multiplier 1-10, and the output signal of the multiplier 1-10 is interfered by an adder 1-6. The interference signal is removed from the output signal of the passive correlator 1-1 containing the signal. The output signal of the adder 1-6 is diversity-combined in the diversity combiner 1-7 using the amplitude and phase of the propagation path obtained from the propagation path estimator 1-9, and the output of the diversity combiner 1-7 The signal is decoded by the decoder 1-8 and output from the output terminal 5-1.

Similarly, the delay unit 2-5 delays the input signal to adjust the addition timing in the adder 2-6. In the interference regenerator 2-4, the decoder 1-3, the propagation path estimator 1-9,
An interference signal is estimated using the signals obtained from the decoder 3-3 and the propagation path estimator 3-9, and the output signal of the interference regenerator 2-4 is subjected to a coefficient r (0 <r) by a multiplier 2-10. <1), and the output signal of the multiplier 2-10 is added to the adder 2-6.
In step (1), the interference signal is removed from the output signal of the passive correlator 2-1 containing the interference signal.

The output signal of the adder 2-6 is diversity-combined in the diversity combiner 2-7 using the amplitude and phase of the propagation path obtained from the propagation path estimator 2-9. The output signal of 7 is decoded by the decoder 2-8 and output from the output terminal 5-2.

Similarly, in the delay unit 3-5, the input signal is delayed to adjust the addition timing in the adder 3-6. In the interference regenerator 3-4, the decoder 1-3, the propagation path estimator 1-9,
An interference signal is estimated using the signals obtained from the decoder 2-3 and the propagation path estimator 2-9, and the output signal of the interference regenerator 3-4 is subjected to a coefficient r (0 <r) by a multiplier 3-10. <1), and the output signal of the multiplier 3-10 is added to the adder 3-6.
In step (1), the interference signal is removed from the output signal of the passive correlator 3-1 containing the interference signal.

The output signal of the adder 3-6 is diversity-combined in the diversity combiner 3-7 using the amplitude and phase of the propagation path obtained from the propagation path estimator 3-9. The output signal of 7 is decoded by the decoder 3-8 and output from the output terminal 5-3. Note that the example of the present embodiment shows a configuration in which a passive correlator is used as the despreading means, but the present invention is not limited to this, and may be a matched filter or a convolver, for example. This is the same for the examples of the other embodiments described below.

In the example of FIG. 1 described above, the interference signal to be removed from the output signal of the delay unit is suppressed by multiplying the output signal of the interference regenerator by the coefficient r, and is input to the interference regenerator. Even if an error is present in the output signal of the multiplexer, there is a feature that errors in demodulated data due to removal of an erroneous interference signal can be reduced. In this example, an example is described in which three processing systems corresponding to three spreading codes are provided. However, in a similar manner, modulation is performed by N (N is an integer of 2 or more) different spreading codes. It is needless to say that an N-sequence configuration for demodulating the obtained signal can be used.

FIG. 2 is a diagram showing a second example of the embodiment of the present invention. In the figure, reference numerals 1-10, 2-1
Reference numerals 0, 3 to 10 denote multipliers.
The same components as those described above are denoted by the same reference numerals. These are the same as in the case of FIG. 1 described above. In the figure, three signals, each modulated by a different spreading code, are received through the same propagation path, and the quasi-coherently detected received baseband signal is matched to the spreading code of each transmission channel. , The passive correlator 1-1, the passive correlator 2-1 and the passive correlator 3-1 to output correlation values from the respective passive correlators.

The output signal of the passive correlator 1-1 is diversity-combined by the diversity combiner 1-2 using the amplitude and phase of the propagation path obtained from the propagation path estimator 1-9. The output signal of -2 is combined with data by the combiner 1-3. Similarly, the output signal of the passive correlator 2-1 is output to the diversity combiner 2- using the amplitude and phase of the channel obtained from the channel estimator 1-9.
2, and the output signal of the diversity combiner 2-2 is decoded by a decoder 2-3.

Similarly, the output signal of the passive correlator 3-1 is
Diversity combining is performed by the diversity combiner 3-2 using the amplitude and phase of the propagation path obtained from the propagation path estimator 1-9, and the output signal of the diversity combiner 3-2 is converted into data by the decoder 3-3. Decrypted. The passive correlator 1-1, the passive correlator 2-1 and the passive correlator 3-
The 1 output signal is input to each of the delay units 1-5, 2-5, and 3-5. The delay unit 1-5 delays the human power signal and adjusts the addition timing in the adder 1-6.

The interference regenerator 1-4 estimates an interference signal using the signals obtained from the decoder 2-3, the decoder 3-3, and the propagation path estimator 1-9. Is multiplied by a coefficient r (0 <r <1) by a multiplier 1-10, and the output signal of the multiplier 1-10 is added to a passive correlator 1-containing an interference signal by an adder 1-6. 1 to remove the interference signal.

The output signal of the adder 1-6 is subjected to diversity combining in the diversity combiner 1-7 using the amplitude and phase of the propagation path obtained from the propagation path estimator 1-9. Data of the output signal of 7 is decoded by the decoder 1-8 and output from the output terminal 5-1. Similarly, the delay unit 2-5 delays the input signal to adjust the addition timing in the adder 2-6.

The interference regenerator 2-4 estimates an interference signal using the signals obtained from the decoder 1-3, the decoder 3-3, and the propagation path estimator 1-9. Is multiplied by a coefficient r (0 <r <1) by a multiplier 2-10, and the output signal of the multiplier 2-10 is added to a passive correlator 2 including an interference signal in an adder 2-6. 1 to remove the interference signal.

The output signal of the adder 2-6 is diversity-combined in the diversity combiner 2-7 using the amplitude and phase of the propagation path obtained from the propagation path estimator 1-9. The output signal of 7 is decoded by the decoder 2-8, and is output from the output terminal 5-2. Similarly, the delay unit 3-5 adjusts the addition timing in the adder 3-6 by delaying the input signal.

The interference regenerator 3-4 estimates an interference signal using the signals obtained from the decoders 1-3, the decoder 2-3 and the propagation path estimator 1-9. Is multiplied by a coefficient r (0 <r <1) by a multiplier 3-10, and the output signal of the multiplier 3-10 is added by an adder 3-6 to a passive correlator 3 including an interference signal. 1 to remove the interference signal.

The output signal of the adder 3-6 is subjected to diversity combining in the diversity combiner 3-7 using the amplitude and phase of the propagation path obtained from the propagation path estimator 1-9. The output signal of 7 is decoded by the decoder 3-8 and output from the output terminal 5-3. Note that the passive correlator 1-1, the passive correlator 2-1 and
The passive correlator 3-1 may be a matched filter or a convolver.

The example of FIG. 2 has a feature that the apparatus scale can be reduced because a propagation path estimator can be commonly used for a plurality of spread code systems received via the same propagation path. In this example, an example corresponding to three spreading codes is described. However, an N-sequence that demodulates a signal modulated by N (N is an integer of 2 or more) different spreading codes by the same method. Is the same as that of the first example.

FIG. 3 is a diagram showing a third example of the embodiment of the present invention. In the figure, reference numerals 1-10, 2-1
0, 3-10, 1-13, 2-13, 3-13 are multipliers, 1-11, 11-1, 3-11 are delay devices, 1-1.
2, 2-12, 3-12 are interference regenerators, l-14, 2-
14, 3-14 are adders, 1-15, 2-15, 3-1
5 is a diversity synthesizer, 1-16, 2-16, 3-
Reference numeral 16 denotes a decoder.
Is the same as

In FIG. 3, three signals modulated by different spreading codes are received through different propagation paths, respectively, and a quasi-coherently detected reception baseband signal is transmitted from an input terminal 4 to each transmission terminal. The signals are input to the passive correlators 1-1, 2-1 and 3-1 matching the spreading codes of the channels, and the respective passive correlators output correlation values.

The output signal of the passive correlator 1-1 is diversity-combined by the diversity combiner 1-2 using the amplitude and phase of the propagation path obtained from the propagation path estimator 1-9. The data of the output signal of -2 is decoded by the decoder 1-3. Similarly, the output signal of the passive correlator 2-1 is output to the diversity synthesizer 2 using the amplitude and phase of the channel obtained from the channel estimator 2-9.
2, and the output signal of the diversity combiner 2-2 is decoded by a decoder 2-3.

Similarly, the output signal of the passive correlator 3-1 is
Diversity combining is performed by the diversity combiner 3-2 using the amplitude and phase of the propagation path obtained from the propagation path estimator 3-9, and the output signal of the diversity combiner 3-2 is converted into data by the decoder 3-3. Decrypted. The passive correlator 1-1, the passive correlator 2-1 and the passive correlator 3-
The 1 output signal is input to each of the delay units 1-5, 2-5, and 3-5.

The delay unit 1-5 delays the input signal to adjust the addition timing in the adder 1-6. Interference regenerator 1
-4, decoder 2-3, propagation path estimator 2-9, decoder 3
-3, an interference signal is estimated using the signal obtained from the propagation path estimator 3-9, and the output signal of the interference regenerator 1-4 is subjected to a coefficient r (0 <r <1) by a multiplier 1-10. Multiplied by
The output signal of the multiplier 1-10 removes the interference signal from the output signal of the passive correlator 1-1 containing the interference signal in the adder 1-6.

The output signal of the adder 1-6 is diversity-combined in the diversity combiner 1-7 using the amplitude and phase of the propagation path obtained from the propagation path estimator 1-9. The output signal 7 is decoded by the decoder 1-8 and output from the output terminal 5-1. Similarly, the delay unit 2-5 delays the input signal to adjust the addition timing in the adder 2-6.

The interference regenerator 2-4 estimates an interference signal using the signals obtained from the decoder 1-3, the propagation path estimator 1-9, the decoder 3-3, and the propagation path estimator 3-9. The output signal of the interference regenerator 2-4 is converted into a coefficient r by a multiplier 2-10.
(0 <r <1). The output signal of the multiplier 2-10 removes the interference signal from the output signal of the passive correlator 2-1 including the interference signal in the adder 2-6.

The output signal of the adder 2-6 is diversity-combined in the diversity combiner 2-7 using the amplitude and phase of the propagation path obtained from the propagation path estimator 2-9. The output signal of 7 is decoded by the decoder 2-8 and output from the output terminal 5-2. Similarly, the delay unit 3-5 adjusts the addition timing in the adder 3-6 by delaying the input signal.

The interference regenerator 3-4 estimates an interference signal using the signals obtained from the decoder 1-3, the channel estimator 1-9, the decoder 2-3, and the channel estimator 2-9. The output signal of the interference regenerator 3-4 is converted into a coefficient r by a multiplier 3-10.
(0 <r <1), and the output signal of the multiplier 3-10 removes the interference signal from the output signal of the passive correlator 3-1 containing the interference signal in the adder 3-6.

The output signal of the adder 3-6 is subjected to diversity combining in the diversity combiner 3-7 using the amplitude and phase of the propagation path obtained from the propagation path estimator 3-9. The output signal of 7 is decoded by the decoder 3-8 and output from the output terminal 5-3. The output signals of the delay units 1-5, 2-5, and 3-5 are input to the delay units 1-11, 2-11, and 3-11, respectively.

The delay unit 1-11 adjusts the addition timing in the adder 1-14 by delaying the input signal. The interference regenerator 1-12 estimates an interference signal using signals obtained from the decoder 2-8, the propagation path estimator 2-9, the decoder 3-8, and the propagation path estimator 3-9. The output signal of the regenerator 1-12 is multiplied by a coefficient r (0 <r <1) by a multiplier 1-13, and the output signal of the multiplier 1-13 is multiplied by the adder 1-12.
At -14, the interference signal is removed from the output signal of the delay unit 1-5 containing the interference signal.

The output signal of the adder 1-14 is diversity-combined in the diversity combiner 1-15 using the amplitude and phase of the propagation path obtained from the propagation path estimator 1-9. The data of the 15 output signals is decoded by the decoder 1-16. Similarly, the delay unit 2-11 adjusts the addition timing in the adder 2-14 by delaying the input signal.

In the interference regenerator 2-12, a decoder 1-8, a channel estimator 1-9, a decoder 3-8, and a channel estimator 3-9
An interference signal is estimated using the obtained signal, and an output signal of the interference regenerator 2-12 is multiplied by a coefficient r (0 <r <1) by a multiplier 2-13, and the multiplier 2-13 In the adder 2-14, the interference signal is removed from the output signal of the delay unit 2-5 containing the interference signal.

The output signal of the adder 2-14 is diversity-combined in the diversity combiner 2-15 using the amplitude and phase of the propagation path obtained from the propagation path estimator 2-9. The data of the 15 output signals is decoded by the decoder 2-16. Similarly, the delay unit 3-11 delays the input signal to adjust the addition timing in the adder 3-14.

In the interference regenerator 3-12, a decoder 1-8, a channel estimator 1-9, a decoder 2-8, and a channel estimator 2-9
An interference signal is estimated using the obtained signal, and an output signal of the interference regenerator 3-12 is multiplied by a coefficient r (0 <r <1) by a multiplier 3-13, and the multiplier 3-13 In the adder 3-14, the interference signal is removed from the output signal of the delay unit 3-5 including the interference signal in the adder 3-14.

The output signal of the adder 3-14 is diversity-combined in the diversity combiner 3-15 using the amplitude and phase of the propagation path obtained from the propagation path estimator 3-9. The data of the 15 output signals is decoded by the decoder 3-16. The passive correlator 1-1, the passive correlator 2-1 and the passive correlator 3-1
May be a matched filter or a convolver.

The example shown in FIG. 3 has a configuration in which the interference signal is reproduced and removed again using data with little error demodulated from the signal from which the interference signal has been removed, so that errors in the demodulated data can be reduced. There are features that you can do. Although this example shows a configuration corresponding to three spreading codes, a similar technique is used to demodulate signals modulated by N (N is an integer of 2 or more) different spreading codes.
The fact that the configuration can be a series is the same as in the other examples described above.

Also, in this example, an interference reproducing means for reproducing an interference signal corresponding to a spreading code, a multiplying means, a delaying means, a subtracting means, a diversity combining means, and a decoding means are provided for each spreading code. Although an example in which two stages are provided is shown, similarly, an interference reproducing unit for reproducing an interference signal corresponding to a spreading code for each of the spreading codes, a multiplying unit, a delaying unit, a subtracting unit, and a diversity combining unit It is also possible to adopt a configuration in which M stages (M is an integer of 1 or more) are provided.

[0057]

As described above, by multiplying the output signal of the interference reproducing means for reproducing the despread interference signal by a coefficient, when the estimated interference signal is different from the actual interference signal, the demodulated data is obtained. There is an advantage that the influence can be reduced and errors in demodulated data can be reduced. Further, the receiving apparatus for spread spectrum communication of the present invention performs interference reproduction and interference removal on the despread signal, and thus has an advantage that digital signal processing becomes easy.

[Brief description of the drawings]

FIG. 1 is a diagram showing a first example of an embodiment of the present invention.

FIG. 2 is a diagram showing a second example of the embodiment of the present invention.

FIG. 3 is a diagram showing a third example of the embodiment of the present invention.

FIG. 4 is a diagram illustrating an example of a configuration of a conventional receiver for spread spectrum communication.

[Explanation of symbols]

1-1,2-1,3-1 Passive correlator 1-2,1-7,, 1-15,2-2,2-7,2-1
5, 3-2, 3-7, 3-15 Diversity synthesizer 1-3, 1-8, 2-3, 2-8, 2-16, 3-3
3-8, 3-16 Decoder 1-4, 1-12, 2-4, 2-12, 3-4, 3-1
2 Interference regenerator 1-5, 1-11, 2-5, 2-11, 3-5, 3-1
1 Delay unit 1-6, 1-14, 2-6, 2-14, 3-6, 3-1
4 Adder 1-9, 2-9, 3-9 Channel Estimator 1-10, 1-13, 2-10, 2-13, 3-10,
3-13 Multiplier 4 input terminal 5-1 to 5-3 output terminal

Claims (3)

[Claims] 1. A receiving apparatus for spread spectrum communication for receiving a plurality of signals spread spectrum by a plurality of different spreading codes, comprising: a despreading means for outputting a despread signal corresponding to the spreading code; Channel estimation means for estimating amplitude / phase characteristics; first diversity synthesis means for performing diversity synthesis of the despread signal using the estimation result of the channel estimation means; and Using the first decoding means for decoding the output signal, the decoding means output of the system corresponding to the other spreading code and the output of the propagation path estimating means, an interference signal to the spreading code system is estimated, and the interference signals are respectively reproduced. Interference reproduction means, multiplication means for multiplying an output signal of the interference reproduction means by a coefficient, delay means for delaying an output signal of the despreading means, Subtraction means for subtracting the output signal of the calculation means to remove interference; second diversity synthesis means for performing diversity synthesis of the output signal of the subtraction means using the estimation result of the propagation path estimation means; And a second decoding unit for decoding an output signal of the diversity combining unit. A plurality of sequences are provided in correspondence with the plurality of different spreading codes. 2. A propagation path estimating means is provided in common for a plurality of spreading code systems received via the same propagation path, and an interference regenerator of each sequence commonly uses an output of the propagation path estimating means. The receiving device for spread spectrum communication according to claim 1, wherein the receiving device has a configuration. 3. The spread using the other delay means for delaying the output signal of the preceding delay means, the output of the composite means corresponding to the preceding stage of the other series, and the output of the propagation path estimation means of the other series. Another interference reproducing means for estimating an interference signal to the code system and reproducing each of the interference signals; another multiplying means for multiplying an output signal of the interference reproducing means by a coefficient; and an output of the multiplying means from the output of the delay means. Another subtracting means for subtracting a signal to remove interference, another diversity combining means for performing diversity combining of an output signal of the subtracting means using an estimation result of the propagation path estimating means, and another diversity combining means. A circuit block comprising another decoding means for decoding the output signal is provided between at least one series of delay means and subtraction means by at least one circuit.
The receiving device for spread spectrum communication according to claim 1 or 2, wherein the receiving device is provided in stages.