JP2853741B2 - CDMA receiver - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a CD of a communication system using a code division multiple access communication system for modulating and transmitting an information signal with a signal having a speed several tens to several hundreds times faster.
It belongs to the MA receiver.

[0002]

2. Description of the Related Art Conventionally, in a cellular digital mobile communication using a code division multiple access communication system, as a technique for removing intersymbol interference generated on a multipath propagation path at the time of reception, an interference canceller using an adaptive equivalent system is known. A system is used. As a prior art of this system, a "CDM" disclosed in Japanese Patent Application Laid-Open No.
A transceiver ".

In this prior art, a reception filter that limits the band of a received signal and a fractionally-spaced equalizer and a filter that sample the received signal at a rate n times (n is an arbitrary integer) by fractional-space equalization are used. A waveform equalizer using a transversal digital filter using an RLS algorithm as a coefficient updating algorithm is provided.

In the prior art, the filter coefficients of the transversal filter are controlled by the RLS algorithm in order to minimize the difference between the output of the transversal digital filter and the desired signal.

Therefore, in the prior art, in order to remove intersymbol interference in a multipath transmission line, the above-mentioned desired signal (usually multiplied by a pilot signal determined in advance between transmission and reception and a spreading code assigned to the user) is used. And the receiving device using this technique is mainly used for a mobile station receiving device which cannot know information of another user during communication.

[0006]

However, in the prior art, the transversal filter coefficient control for performing the above-described interference cancellation is problematic in that, in some cases, the power is wasted but does not contribute to the improvement of the quality of the received signal. There is a point.

That is, in the case of communication of one base station versus a plurality of mobile stations as in a cellular system, the downlink signals received by the mobile stations are synchronized with each user, so that interference between users is logical. Because it is not.

Therefore, what is recognized as an interference signal by the mobile station is a signal in the own cell which arrives at the mobile station as a multipath or a signal which is asynchronous from the own cell which arrives from another cell.

When there is no adjacent base station in the large zone system, only multipath signals in the zone are recognized as interference signals by the mobile station.

[0010] When these interference signals are present, the conventional interference canceller operates effectively and can improve the quality of the received signal.
If there is no multipath or interference signal from another cell, the calculation of the RLS algorithm and the operation of updating the filter coefficient become useless. In particular, a portable mobile station having a limited power supply is required to reduce power consumption as much as possible, but on the contrary, consumes unnecessary power.

[0011] Therefore, an object of the present invention is to suppress the operation without the need for an interference canceller in a communication system for communicating information using spread spectrum, especially when a single-user type interference canceller is used on the mobile station side. And CDMA that can minimize power consumption
A receiving device is provided.

[0012]

SUMMARY OF THE INVENTION In a spread spectrum communication system for modulating and transmitting an information signal with a spread signal having a speed of several tens to several hundreds times that of the information signal, a signal for holding a quadrature demodulated received signal is provided. I-axis and Q-axis storage means, and I-axis and Q-axis realizing a correlation filter capable of adaptively changing coefficients for despreading a received signal.
An adaptive filter for axes, a selection unit for selecting a filter coefficient to be applied to the adaptive filter, a spreading code generation unit for generating a coefficient of the adaptive filter, or a filter coefficient of a sliding correlator described below, Coefficient updating means for calculating a coefficient for equalizing distortion of a transmission line applied to a filter; detecting means for demodulating a received signal to extract an information signal; and gradually outputting a received signal and an output of the spreading code generating means. I-axis and Q-axis sliding correlators for detecting the maximum correlation point while shifting, and squaring means for the I-axis and Q-axis for squaring the output of the sliding correlator to obtain a power-dimensional signal. And the outputs of the I-axis and Q-axis squaring means to generate a desired signal power value,
Addition means for detecting the timing of the maximum correlation point; timing generation means for generating a reference timing for reception; delay means for delaying the output of the timing generation means in accordance with the output of the sliding correlator; A first storage unit for storing a reference value of a power dimension signal which is an output of the addition unit, an output of the addition unit and an output of the first storage unit are compared, and the number of times that the condition is satisfied is coefficientd. The first comparing means, the second storing means for storing the reference value of the counting result which is the output of the first comparing means, and the counting result output from the first comparing means and the output of the second storing means. A CDMA receiving apparatus is provided, comprising: a comparison unit that outputs a control signal to the selection unit and the coefficient updating unit.

[0013]

According to the CDMA receiving apparatus of the present invention, for example, when there is no adjacent base station in a large zone wireless system, switching of the receiving system is performed by the number of paths, and in a cellular system, switching of the receiving system is performed by the quality of a received signal. And a measuring device for each determination signal (the number of paths and the reception quality) so as to control the switching of the reception method based on both the number of paths and the reception quality in order to accurately grasp the reception state at the mobile station. And a reception system switch, and when unnecessary, the operation of the interference canceller is stopped to perform a normal matched filter reception.

According to the present invention, when the presence of the above-mentioned interference signal is recognized based on the number of paths and the reception quality, the interference canceller operates effectively and can improve the quality of the reception signal. When there is no interference signal in the place where the current position is, the calculation of the RLS algorithm and the operation of updating the filter coefficient are stopped to reduce the power consumption.

[0015]

Next, first and third embodiments of the CDMA receiver according to the present invention will be described with reference to the drawings. The CDMA receivers of the first and third embodiments are employed in a spread spectrum communication system for modulating and transmitting an information signal with a spread signal having a speed of several tens to several hundred times that of the information signal. .

FIG. 1 shows a CDM according to a first embodiment of the present invention.
FIG. 3 is a circuit configuration diagram of an A receiving device. FIG. 2 is a circuit configuration diagram of the CDMA receiver according to the second embodiment of the present invention. FIG. 3 is a circuit configuration diagram of the CDMA receiver according to the third embodiment of the present invention.

In FIG. 1, a CDMA receiving apparatus according to a first embodiment of the present invention includes an I register (I axis storage means) 101 for holding a quadrature demodulated received signal and a Q register (Q axis). Storage means) 102, an I-axis correlation filter (I-axis adaptive filter) 103 and a Q-axis correlation filter (Q-axis correlation filter) for realizing a correlation filter capable of adaptively changing a coefficient for despreading a received signal. (An adaptive filter) 104 and a selector (selecting means) 105 for selecting a filter coefficient to be applied to the I-axis correlation filter 103 and the Q-axis correlation filter 104.

Further, the CDMA receiver includes a spreading code generator for generating coefficients of the I-axis correlation filter 103 and the Q-axis correlation filter 104 or filter coefficients of an I-axis sliding correlator 111 and a Q-axis sliding correlator 112, which will be described later. (Spreading code generating means) 106, a coefficient updater (coefficient updating means) 107 for calculating a coefficient for equalizing distortion of a transmission line applied to the I-axis correlation filter 103 and the Q-axis correlation filter 104, and a received signal A detector (detection means) 108 for demodulating and extracting an information signal;
An I-axis sliding correlator 111 and a Q-axis sliding correlator 112 for detecting a maximum correlation point while slightly shifting the output of the received signal and the output of the spreading code generator 106 are provided.

Further, the CDMA receiving apparatus squares the outputs of the I-axis sliding correlator 111 and the Q-axis sliding correlator 112 to generate a power-dimensional signal as an I-axis squarer (I-axis squarer). 113 and the outputs of the squarer for the Q axis (squaring means for the Q axis) 114 and the outputs of the squarers 113 and 114 for the I axis and the Q axis to generate a desired signal power value, and the maximum correlation Adder (addition means) 115 for detecting the timing of a point, and timing generation circuit (timing generation means) 110 for generating a reference timing for reception
And a delay unit (delay means) 109 for delaying the output of the timing generation circuit 110 in accordance with the outputs of the I-axis sliding correlator 111 and the Q-axis sliding correlator 112.
A first pulse level threshold value register (first storage means) 117 for storing a reference value of a power dimension signal output from the adder 115; an output of the adder 115 and a pulse level threshold value A first comparator that compares the output of the register 117 and counts the number of times that the condition is satisfied (first comparing means)
116, a second pulse level threshold register (second storage means) 118 for storing a reference value of the counting result output from the comparator 116, and a counting result output from the first comparator 116 Second pulse level threshold register 118
And outputs a control signal to the selector 105 and the coefficient updater 107 (second comparing means) 11
9 is provided.

Next, the CDM according to the first embodiment of the present invention
The operation of the A receiver will be described with reference to FIG.

In FIG. 1, the orthogonally demodulated received signal is input to an I-axis sliding correlator 111 and a Q-axis sliding correlator 112. In the I-axis sliding correlator 111 and the Q-axis sliding correlator 112,
The cross-correlation between the replica of the spreading code used on the transmission side and the I-axis and Q-axis of the received signal generated by the spreading code generator 106 while shifting by 1 / n chips (n is an arbitrary integer) is m symbols. Minutes (m is any integer) are calculated.

The calculated cross-correlation values are squared by the I-axis and Q-axis squarers 113 and 114 for the I-axis and the Q-axis for each 1 / n chip, and added by the adder 115. You. The adder 115 extracts the timing at which the maximum value of the cross-correlation value is obtained and supplies the extracted timing to the delay unit 109. The delay unit 109 instructs the timing position so that the output of the timing generation circuit 110 is delayed so that the I register 101 and the Q register 102 can receive the received signal at the optimal timing.

Further, the adder 115 outputs the power value of the desired signal by adding the square value of the I-axis signal and the square value of the Q-axis signal, and the output is output from the first comparator 116 to the level of the path. The threshold value is compared with a first pass level threshold value register 117 which holds the threshold value.

If the output of the adder 115 is larger than the value of the first threshold register 117, it is counted as a valid reception path. The second comparator 119 compares the counted number of valid paths with the output of the second path number threshold register 118 that holds the threshold of the number of paths, and determines that the number of valid paths is equal to the second number. If the value is smaller than the value held in the pass number threshold register 118, the second comparator 119
5 to the I-axis correlation filter 103 and the Q-axis correlation filter 104 as spreading code generators 106 as despreading coefficients.
Gives the output of

If the number of valid passes is larger than the value stored in the second pass number threshold register 118, the second comparator 119 operates the selector 105 to cause the I-axis correlation filter 103, Q The output of the coefficient updater 107 is given to the axis correlation filter 104 as a coefficient for despreading.

The received signals input to the I-register 101 and the Q-register 102 as the I-axis signal and the Q-axis signal, respectively, are used by the I-register 101 and the Q-register 102 to determine the time position generated by the timing generator 110 by the delay unit 109. Arbitrary k symbols (k is an arbitrary integer) are sequentially fetched from the time position delayed by the designated delay amount, and input to the I-axis correlation filter 103 and the Q-axis correlation filter 104.

In the I-axis correlation filter 103 and the Q-axis correlation filter 104, a replica of the spreading code used on the transmitting side generated by the spreading code generator 106 selected by the selector 105 or selected by the selector 105. The I-axis and the Q-axis are respectively determined by the filter coefficients that compensate for the distortion of the communication path and the interference signal output from the updated coefficient updater 107.
Perform axis despreading.

The coefficient updater 107 uses a known pilot signal included in the received signal and performs an RLS algorithm, an LMS algorithm, or the like, and compares the received signal output from the I-axis correlation filter 103 and the Q-axis correlation filter 104 with the known signal. The filter coefficients of the I-axis correlation filter 103 and the Q-axis correlation filter 104 are changed from replicas of spread signals to coefficients for compensating for distortion on the communication channel so that the error power of the signal is minimized.

In the coefficient updating unit 107, a comparator 119
If the output of the spread code generator 106 is selected as a filter coefficient by the selector 105 according to the output of the above, the operation is stopped, and the calculated filter coefficient is also reset to the output of the spread code generator 106.

The received signal despread by the I-axis correlation filter 103 and the Q-axis correlation filter 104 is input to a detector 108 and a coefficient updater 107. The detector 108 detects the outputs of the I-axis correlation filter 103 and the Q-axis correlation filter 104 and extracts the transmitted information signal as demodulated data.

Next, the CDMA according to the second embodiment of the present invention
The receiving device will be described.

In FIG. 2, a CDMA receiving apparatus according to a second embodiment of the present invention includes an I register (storage means for I axis) 101 and a Q register (Q axis) for holding a quadrature demodulated received signal. Storage means) 102, an I-axis correlation filter (I-axis adaptive filter) 103 and a Q-axis correlation filter (Q-axis correlation filter) for realizing a correlation filter capable of adaptively changing a coefficient for despreading a received signal. (An adaptive filter) 104 and a selector (selecting means) 105 for selecting a filter coefficient to be applied to the I-axis correlation filter 103 and the Q-axis correlation filter 104.

Further, the CDMA receiver includes a spread code generator for generating coefficients of the I-axis correlation filter 103 and the Q-axis correlation filter 104 or filter coefficients of an I-axis sliding correlator 111 and a Q-axis sliding correlator 112 described later. (Spreading code generating means) 106, a coefficient updater (coefficient updating means) 107 for calculating a coefficient for equalizing distortion of a transmission line applied to the I-axis correlation filter 103 and the Q-axis correlation filter 104, and a received signal A detector (detection means) 108 for demodulating and extracting an information signal;
An I-axis sliding correlator 111 and a Q-axis sliding correlator 112 for detecting a maximum correlation point while slightly shifting the output of the received signal and the output of the spreading code generator 106 are provided.

Further, the CDMA receiving apparatus squares the outputs of the I-axis sliding correlator 111 and the Q-axis sliding correlator 112 to obtain a power-dimensional signal as an I-axis squarer (I-axis squarer). 113 and the outputs of the squarer for the Q axis (square means for the Q axis) 114 and the outputs of the squarers 113 and 114 for the I axis and the Q axis to generate a desired signal power value, Adder (first adding means) for detecting the timing of the above, and a timing generating circuit (timing generating means) 1 for generating a reference timing for reception 1
10 is provided.

Further, the CDMA receiver has an I-axis and a Q-axis.
A delay unit (delay means) 109 for delaying the output of the timing generation circuit 110 in accordance with the outputs of the axis sliding correlators 111 and 112, and a second I-axis for calculating a power dimension signal of the received signal. Squarer (second I-axis squaring means) 120 and second Q-axis squaring means (second Q-axis means) 121, second I-axis and Q-axis squaring Adder (second adding means) 122 that adds the outputs of the adders 120 and 121 to a received signal power value, and the desired signal power value output from the first adder 115 and the second adder A subtractor (subtraction unit) 123 that outputs a difference between the received signal power values output from the subtracter 122 to a divider (division unit) 124 described later, an output of the first adder 115 and the subtractor 12.
3 which calculates the ratio of the outputs of the three and uses it as the reception quality signal
24, an SIR threshold register (storage means) 12 for storing a reference value of the reception quality signal output from the divider 124.
5, the output of the divider 124 and the output of the SIR threshold register 125 are compared, and the selector 105 and the coefficient updater 1
And a second comparator (second comparing means) 126 for outputting a control signal to the control signal 07.

Next, the CDM according to the second embodiment of the present invention
The operation of the A receiver will be described with reference to FIG.

In FIG. 2, I register 101, Q register 102, I axis correlation filter 103, Q axis correlation filter 104, selector 105, spreading code generator 106, coefficient updater 107, detector 108, delay unit 109, A timing generation circuit 110, an I-axis sliding correlator 111,
Q-axis sliding correlator 112, squarers 113 and 11
4. The operation of the adder 115 is the same as the operation described in the first embodiment, and will not be described. In the present embodiment, the selector 105 and the coefficient updater 1 in the first embodiment
The control signal 07 is changed from one based on the number of reception paths to one based on the received signal quality.

In this embodiment, the input I-axis and Q-axis signals are squared by second squarers 120 and 121, respectively, and added by a second adder 122. Since the output of the second adder 122 represents the total power of the received signal and the output of the first adder 115 represents the received power of the desired signal, the difference is the power of the interference signal.

Therefore, the power of the desired signal is subtracted from the total power of the received signal by the subtractor 123 to become the power of the interference signal. The divider 124 calculates the ratio of the power of the desired signal output from the first adder 115 to the power of the interference signal output from the subtractor 123, and calculates a desired signal to interference signal ratio (hereinafter referred to as SIR) representing reception quality information. ).

In the comparator 126, the SIR threshold value output from the SIR ratio threshold value register 125 and the SI
The R values are compared, and if the SIR value of the received signal is larger than the SIR threshold value output from the SIR ratio threshold value register 125, the second comparator 126 operates the selector 105,
The output of the spreading code generator 106 is given to the I-axis correlation filter 103 and the Q-axis correlation filter 104 as despreading coefficients.

If the received signal is smaller than the SIR threshold output from the SIR ratio threshold register 125,
The second comparator 126 operates the selector 105 to supply the I-axis correlation filter 103 and the Q-axis correlation filter 104 with the output of the coefficient updater 107 as a coefficient for despreading.

Next, the CDMA according to the third embodiment of the present invention
The receiving device will be described.

Referring to FIG. 3, a CDMA receiver according to the first embodiment of the present invention includes an I register 101, a Q register 102, an I axis correlation filter 103, and a Q axis correlation filter 1.
04, selector 105, spreading code generator 106, coefficient updater 107, detector 108, delay unit 109, timing generation circuit 110, I-axis sliding correlator 111, Q-axis sliding correlator 112, for the first I-axis The squarer 1
13, a first Q-axis squarer 114, a second I-axis squarer 120, a second Q-axis squarer 121, a first adder 115, a second adder 122, One comparator 116,
Second comparator 119, third comparator 126, pass level threshold register (first storage means) 117, pass number threshold register (second storage means) 122, subtractor 12
3. Divider 124, SIR ratio threshold register 125
(Third storage means), AND circuit (logical product circuit) 127
Consists of

Next, the CDM according to the third embodiment of the present invention will be described.
The operation of the A receiver will be described with reference to FIG.

In FIG. 3, an I register 101, a Q register 102, an I axis correlation filter 103, a Q axis correlation filter 104, a selector 105, a spreading code generator 106, a coefficient updater 107, a detector 108, a delay unit 109, A timing generation circuit 110, an I-axis sliding correlator 111,
Q-axis sliding correlator 112, first I-axis squarer 113, first Q-axis squarer 114, second I-axis squarer 120, second Q-axis squarer 121 , First adder 115, second adder 122, first comparator 11
6, operation of second comparator 119, third comparator 126, pass level threshold register 117, pass number threshold register 118, subtractor 123, divider 124, and SIR ratio threshold register 125 Are the same as the operations described in the first and second embodiments, and will not be described.

In the present embodiment, the control signals of the selector 105 and the coefficient updater 107 in the first and second embodiments are combined based on the number of reception paths or the received signal quality alone. To the information based on that information.

In the present embodiment, the AND circuit 127
The logical product of the control signal generated from the number of reception paths output from the second comparator 119 and the control signal generated from the received signal quality SIR ratio output from the third comparator 126 is obtained. As a result, the number of valid paths becomes equal to
8 and the SIR value of the received signal is larger than the SIR threshold value output from the SIR ratio threshold value register 125, the AND circuit 127 selects the selector 10
5 to the I-axis correlation filter 103 and the Q-axis correlation filter 104 as spread signal generators 106 as despreading coefficients.
Gives the output of

Further, the number of valid paths is larger than the value held in the number-of-passes threshold register 118 and the S
The IR value is the S value output from the SIR ratio threshold value register 125.
If it is smaller than the threshold value of the IR, the AND circuit 127 operates the selector 105 to cause the I-axis correlation filter 103 and the Q-axis correlation filter 104 to output the coefficient updater 1 as a despreading coefficient.
07 output.

[0049]

As described above, according to the CDMA receiving apparatus of the present invention, when there is no adjacent base station in a large zone wireless system, switching of the receiving method by the number of paths is performed. In the system, the switching of the receiving system based on the quality of the received signal, and in order to more accurately grasp the receiving state at the mobile station, the switching of the receiving system based on both the number of paths and the receiving quality is controlled. Signal (number of paths and reception quality) and a reception mode switcher, and the operation of the interference canceller is stopped when it is not necessary. At a minimum, power consumption can be reduced.

Further, a CDMA receiver using a single-user type interference canceller can be obtained.

[Brief description of the drawings]

FIG. 1 is a circuit configuration diagram showing a CDMA receiver according to a first embodiment of the present invention.

FIG. 2 is a circuit configuration diagram showing a CDMA receiver according to a second embodiment of the present invention.

FIG. 3 is a circuit diagram illustrating a CDMA receiver according to a third embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 101 I register 102 Q register 103 I axis correlation filter 104 Q axis correlation filter 105 Selector 106 Spread code generator 107 Coefficient updater 108 Detector 109 Delay unit 110 Timing generation circuit 111 I axis sliding correlator 112 Q axis sliding correlator 113, 114, 120, 121 Squarer 115, 122 Adder 116, 119, 126 Comparator 117 Pass level threshold register 118 Pass number threshold register 123 Subtractor 124 Divider 125 SIR ratio threshold register 127 AND circuit

Continuation of the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) H04J 13/04 H04B 3/06

Claims (3)

(57) [Claims] 1. A spread spectrum communication system for modulating and transmitting an information signal with a spread signal having a speed of several tens to several hundreds times that of an information signal, comprising: an I-axis for holding a quadrature demodulated received signal; Storage means, and storage means for the Q axis, an adaptive filter for the I axis, and an adaptive filter for the Q axis, which realizes a correlation filter capable of adaptively changing coefficients for despreading a received signal; Selecting means for selecting a filter coefficient to be applied to the adaptive filter; spreading code generating means for generating a coefficient of the adaptive filter or a filter coefficient of a sliding correlator to be described later; and a distortion of a transmission path applied to the adaptive filter Coefficient updating means for calculating a coefficient for equalizing, and demodulating a received signal to extract an information signal A detecting correlator, an I-axis sliding correlator, and a Q-axis sliding correlator for detecting a maximum correlation point while slightly shifting a received signal and an output of the spreading code generating means, and the sliding correlator. The outputs of the I-axis and Q-axis squaring means are summed with the outputs of the I-axis and Q-axis squaring means to obtain the desired signal power value. Adding means for generating the timing of the maximum correlation point; timing generating means for generating a reference timing for reception; delay means for delaying the output of the timing generating means in accordance with the output of the sliding correlator And, a first storage unit that stores a reference value of a power dimension signal that is an output of the addition unit, and compares an output of the addition unit and an output of the first storage unit, A first comparing means for counting the number of times satisfying the condition, a second storage means for storing a reference value of the counting result which is an output of the first comparing means, and a counting result outputted from the first comparing means. A receiving device for CDMA, comprising: a second comparing unit that compares outputs of two storing units and outputs a control signal to the selecting unit and the coefficient updating unit. 2. A spread spectrum communication system for modulating and transmitting an information signal with a spread signal having a speed of several tens to several hundred times that of an information signal, comprising: an I-axis for holding a quadrature demodulated received signal; Storage means, and storage means for the Q axis, an adaptive filter for the I axis, and an adaptive filter for the Q axis, which realizes a correlation filter capable of adaptively changing coefficients for despreading a received signal; Selecting means for selecting a filter coefficient to be applied to the adaptive filter; spreading code generating means for generating a coefficient of the adaptive filter or a filter coefficient of a sliding correlator to be described later; and a distortion of a transmission path applied to the adaptive filter Coefficient updating means for calculating a coefficient for equalizing, and demodulating a received signal to extract an information signal Detecting means, I-axis and Q-axis sliding correlators for detecting the maximum correlation point while slightly shifting the received signal and the output of the spreading code generating means, and squaring the outputs of the sliding correlators. Then, the outputs of the first I-axis squaring means and the first Q-axis squaring means as power dimension signals, and the outputs of the I-axis and Q-axis squaring means are added to obtain a desired signal. A first adding means for generating a power value and detecting a timing of a maximum correlation point; a timing generating means for generating a reference timing for reception; and an output of the timing generating means in accordance with an output of the sliding correlator. And a second I for calculating a signal of the power dimension of the received signal.
Axis squaring means, and Q-axis squaring means, and second adding means for adding outputs of the second I-axis, and Q-axis squaring means to obtain a received signal power value; The difference between the desired signal power value output by the first addition means and the received signal power value output by the second addition means, subtraction means that outputs the result to division means described below, and the output of the first addition means A dividing unit that calculates a ratio of the outputs of the subtracting unit and sets it as a reception quality signal; a storage unit that stores a reference value of the reception quality signal output by the division unit; an output of the division unit; A receiving device for CDMA, comprising: comparing means for comparing outputs and outputting a control signal to said selecting means and coefficient updating means. 3. A spread spectrum communication system for modulating and transmitting an information signal with a spread signal having a speed of several tens to several hundreds times that of an information signal, wherein an I-axis signal for holding a quadrature demodulated received signal is provided. Storage means, storage means for the Q axis, adaptive filters for the I axis and the Q axis for realizing a correlation filter capable of adaptively changing coefficients for despreading the received signal, and an adaptive filter for the Q axis. A selection unit for selecting a filter coefficient to be applied; a spreading code generation unit for generating a coefficient of the adaptive filter or a filter coefficient of a sliding correlator to be described later; and a transmission line distortion applied to the adaptive filter are equivalent. Coefficient updating means for calculating a coefficient for detecting, a detecting means for demodulating a received signal to extract an information signal, and a receiving signal And the output of the spreading code generating means, while gradually shifting the output of the sliding correlator for the I-axis sliding correlator and the Q-axis sliding correlator for detecting the maximum correlation point, The outputs of the first I-axis squaring means and the Q-axis squaring means as a dimensional signal and the outputs of the first I-axis and Q-axis squaring means are added, and a desired signal power value is obtained. First adding means for generating and detecting the timing of the maximum correlation point; timing generating means for generating a reference timing for reception; and delaying the output of the timing generating means in accordance with the output of the sliding correlator. Delay means, first storage means for storing a reference value of a power dimension signal which is the output of the first addition means, and comparing the output of the addition means with the output of the first storage means. A first comparing unit that counts the number of times that the condition is satisfied; a second storage unit that stores a reference value of a counting result that is an output of the second comparing unit; and a counting result that is output by the first comparing unit. And a second comparing means for comparing the output of the second storing means with the output of the selecting means and the control signal for the coefficient updating means to an AND circuit to be described later, and further calculating a power dimension signal of the received signal. A second I-axis squaring means and a Q-axis squaring means for adding the outputs of the second I-axis and Q-axis squaring means to obtain a received signal power value. A second adding unit; a subtracting unit that outputs a difference between a desired signal power value output from the first adding unit and a received signal power value output from the second adding unit to a dividing unit described below; The ratio between the output of the adding means and the output of the subtracting means is calculated and used as the reception quality signal. Division means, a third storage means for storing a reference value of the reception quality signal output from the division means, and an output of the division means and an output of the third storage means, and an AND circuit described later The selecting means, the third comparing means for outputting a control signal for coefficient updating means, the second comparing means, and the logical product of the output values of the third comparing means, the selecting means, the coefficient And a logical product circuit for controlling the updating means.
A receiving device.