JP6809814B2 - Signal detection device and signal detection method - Google Patents

Description

The present invention relates to a signal detection device and a signal detection method, and more particularly to a signal detection device and a signal detection method for detecting a modulated signal with high time accuracy.

In radar and communication, the transmission signal and the synchronization signal that is a part of the transmission signal are used as reference signals to obtain the correlation value between the reference signal and the reception signal, and the synchronization timing or reception signal of the reception signal is obtained based on the obtained correlation value. A method of detecting itself is known. At that time, if the received signal has a large frequency offset, the peak value of the correlation value drops remarkably, and it becomes difficult to detect the signal or synchronization. Therefore, signal detection and synchronous detection using correlation require processing for estimating and correcting the frequency offset of the received signal (see, for example, Patent Documents 1 and 2).

Further, in relation to the present invention, Patent Document 3 describes a synchronous detection device for received signals, and Patent Document 4 describes a radar device having a function of calculating a correlation value between a received signal and a delay signal. Patent Document 5 describes an equalizing device used for a QAM (Quadrature Amplitude Modulation) signal, and Patent Document 6 describes an AFC (Automatic Frequency Control) processing device having a delayed detection processing function.

Japanese Unexamined Patent Publication No. 2013-046382 JP-A-11-109027 Japanese Unexamined Patent Publication No. 2014-179823 Japanese Unexamined Patent Publication No. 2012-251820 JP-A-2002-344362 Japanese Unexamined Patent Publication No. 2006-115206

Patent Document 1 discloses a method of detecting synchronization by a simple process based on the correlation between the delayed detected received signal and the preamble pattern. However, with the general delayed detection method described in Patent Document 1, it is difficult to detect synchronization with high time accuracy for a constant envelope signal, as will be described later. Further, in the technique described in Patent Document 2, in order to process an unknown frequency offset due to Doppler shift, it is necessary to arrange and process a plurality of correction functions having different frequency offsets in parallel. That is, since the technique described in Patent Document 2 requires a plurality of frequency correction functions, there is a problem that the circuit scale and the processing load increase. Further, Patent Document 3-6 does not disclose a technique for detecting the detection timing or synchronization timing of a received signal with high time accuracy.

(Purpose of Invention)
An object of the present invention is to provide a technique for detecting at least one of a received signal detection timing and a synchronization timing with high accuracy with a simple configuration.

The signal detection device of the present invention performs delayed detection by delaying a reference signal generator that generates a reference signal for detecting a correlation with a received signal and the reference signal by N samples (N is an integer of 2 or more) time. A first delay detection unit that outputs the delayed-detected reference signal, and a second delayed detection that delays the received signal by N sample times to perform delayed detection and outputs the delayed-detected received signal. At least the detection timing and synchronization timing of the received signal based on the mutual correlation value, the correlation unit for obtaining the mutual correlation value between the output of the first delay detection unit and the output of the second delay detection unit. A determination unit that outputs a timing signal indicating one of them is provided.

In the signal detection method of the present invention, a reference signal for detecting a correlation with a received signal is generated, the reference signal is delayed by an N (N is an integer of 2 or more) sample time, delayed detection is performed, and the received signal is detected. Is delayed by N sample times to perform delayed detection, and the cross-correlation value between the imaginary part component of the reference signal that has been delayed detected and the imaginary part component of the received signal that has been delayed detected is obtained and used as the cross-correlation value. Based on this, a timing signal indicating at least one of the detection timing and the synchronization timing of the received signal is output.

The signal detection program of the present invention causes a computer of a signal detection device to generate a reference signal for detecting a correlation with a received signal, a procedure for delaying the reference signal by one sample time to perform delayed detection, and a delayed detection. A procedure for outputting only the imaginary part component of the reference signal, a procedure for delaying the received signal by one sample time for delayed detection, a procedure for outputting only the imaginary part component of the delayed detected received signal, and a delayed detection. A procedure for obtaining a mutual correlation value between the imaginary part component of the reference signal and the delayed detection imaginary part component of the received signal, and at least the detection timing and synchronization timing of the received signal based on the mutual correlation value. The procedure for outputting a timing signal indicating one of them is executed.

The present invention makes it possible to detect at least one of the detection timing and the synchronization timing of the received signal with high accuracy with a simple configuration.

It is a block diagram which shows the structural example of the receiver 100 of 1st Embodiment. It is a block diagram which shows the structural example of a signal detector 5. It is a block diagram which shows the structural example of the delay detectors 12 and 13. It is a flowchart which shows the example of the operation procedure of a signal detector 5. This is an example of a graph showing the amplitude of the complex signal output from the complex multiplier 102. It is a block diagram which shows the structural example of the receiver 200 of 2nd Embodiment. It is a block diagram which shows the structural example of a signal detector 51. It is a block diagram which shows the structural example of the delay detectors 22 and 23. It is a flowchart which shows the example of the operation procedure of a signal detector 51.

(First Embodiment)
FIG. 1 is a block diagram showing a configuration example of the receiver 100 according to the first embodiment of the present invention. The receiver 100 includes an antenna 1, an A / D (analog to digital) converter 2, an orthogonal detector 3, a demodulator 4, and a signal detector 5. The antenna 1 receives the radio signal and outputs the received signal to the A / D converter 2. The A / D converter 2 converts the signal input from the antenna 1 into a digital signal. The signal received by the antenna 1 may be converted (down-converted) to a low frequency before being input to the A / D converter 2. The A / D converter 2 converts the input signal into a digital signal and outputs it to the orthogonal detector 3. The orthogonal detector 3 orthogonally detects the digital signal input from the A / D converter 2 and generates a received signal. The received signal is a complex signal having a real part and an imaginary part. The received signal is output to the demodulator 4 and the signal detector 5.

The signal detector 5 generates a timing signal based on the complex signal generated by the orthogonal detector 3 and outputs the timing signal to the demodulator 4. The timing signal indicates at least one of the detection timing and the synchronization timing of the received signal in the demodulator 4. These timings are indicated, for example, by the rising edge of the timing signal, but the timings may be indicated by other means. The configuration and operation of the signal detector 5 will be further described later. Hereinafter, "at least one of the detection timing and the synchronization timing of the received signal" will be referred to as "signal detection / synchronization timing".

A reception signal and a timing signal are input to the demodulator 4. The demodulator 4 demodulates the received signal, which is a complex signal, based on the timing indicated by the timing signal. In the receiver 100, since the components other than the signal detector 5 are known as general receiver components, detailed description of each configuration and operation will be omitted.

The signal detector 5 will be described below. FIG. 2 is a block diagram showing a configuration example of the signal detector 5 provided in the receiver 100. The signal detector 5 includes a reference signal generator 11, delay detectors 12 and 13, a correlator 14, and a determination device 15.

The reference signal generator 11 generates a reference signal and outputs it to the delay detector 12. The reference signal is a signal used to calculate the mutual correlation value with the received signal. The reference signal is a complex signal having a format corresponding to the received signal, and the format is selected according to the signal received by the receiver 100. In the present embodiment, the reference signal and the received signal are constant envelope signals. The reference signal is, for example, a chirp signal or an FSK (frequency shift keying) signal. The reference signal may be generated based on the transmission signal used in the transmitter used in pair with the receiver 100.

For example, when the received signal is an FSK signal and the signal detector 5 is used for synchronous detection, the reference signal generator 11 is included in the FSK-modulated transmitted signal having the same format as the received signal. The signal may be generated as a reference signal. When the signal detector 5 is used in the receiving unit of a chirp type radar, the entire chirp signal transmitted by the radar may be used as a reference signal. By using the chirp signal of the radar as a reference signal, when the receiver 100 is provided in the radar, the detection timing of the chirp signal can be known from the timing signal output by the signal detector 5. As described above, as the reference signal, a signal capable of detecting the signal detection / synchronization timing based on the cross-correlation value with the received signal in the correlator 14 is selected.

The delay detector 12 delay-detects the reference signal and outputs only the imaginary component of the delayed-detected signal to the correlator 14. The delay detector 13 delay-detects the received signal output from the orthogonal detector 3 provided in the receiver 100, and outputs only the imaginary component of the delayed-detected signal to the correlator 14. The correlator 14 calculates the cross-correlation value between the signal output from the delay detector 12 and the signal output from the delay detector 13, and outputs the cross-correlation value to the determination device 15. The determination device 15 compares the cross-correlation value output from the correlator 14 with a preset threshold value, and determines signal detection or synchronization detection based on the comparison result. The determination result is output from the determination device 15 to the demodulator 4 in FIG. 1 as a timing signal. The determination device 15 has a function of detecting the peak of the cross-correlation value, and may output a timing signal when the peak exceeds the threshold value.

FIG. 3 is a block diagram showing a configuration example of the delay detectors 12 and 13 shown in FIG. The delay detectors 12 and 13 have a similar configuration. The delay detectors 12 and 13 include a one-sample delayer 101, a complex multiplier 102, and an imaginary output device 103. A reference signal is input from the reference signal generator 11 to the one-sample delayer 101 and the complex multiplier 102 of the delay detector 12. A received signal is input from the orthogonal detector 3 to the one-sample detector 101 and the complex multiplier 102 of the delay detector 13. The 1-sample delayer 101 delays the input signal by 1 sample and outputs the complex conjugate signal. In FIG. 3, the “*” mark attached to the complex multiplier 102 indicates that the signal input to the complex multiplier 102 is the complex conjugate signal of the output of the one-sample delayer 101.

The complex multiplier 102 complex-multiplies the input signal to the delay detector 12 or 13 and the complex conjugate signal of the output of the one-sample delayer 101, and outputs the complex multiplication result to the imaginary part output device 103. That is, the complex multiplier 102 of the delay detector 12 complex-multiplies the reference signal and the complex conjugate signal of the signal obtained by delaying the reference signal by one sample, and outputs the result to the imaginary part output device 103. The complex multiplier 102 of the delay detector 13 complex-multiplies the received signal and the complex conjugate of the signal whose received signal is delayed by one sample, and outputs the result to the imaginary part output device 103. The imaginary part output device 103 outputs only the imaginary part from the complex multiplication result of the complex multiplier 102. The output of the imaginary part output device 103 is input to the correlator 14.

FIG. 4 is a flowchart showing an example of the operation procedure of the signal detector 5. As described above, the delay detector 12 and the delay detector 13 delay detect the reference signal and the received signal, which are complex signals, respectively (step S01 in FIG. 4), extract only the imaginary component from the result, and correlate the correlator. Output to 14 (step S02). The correlator 14 calculates and outputs a cross-correlation value between the imaginary part component of the delayed-detected reference signal and the imaginary part component of the delayed-detected received signal (step S03). The determination device 15 detects the peak of the cross-correlation value and outputs the signal detection / synchronization timing based on the timing indicated by the peak of the cross-correlation value (step S04).

The function of the signal detector 5 may be realized only by hardware, or is realized by executing a program by a central processing unit (CPU) or a digital signal processor (DSP). You may.

The signals in the delay detectors 12 and 13 shown in FIG. 3 will be described. The delay detectors 12 and 13 complex-multiply the input complex signal (that is, the reference signal or the received signal) with the signal obtained by complex-conjugating the signal delayed by one sample with the complex multiplier 102.

・・・ 式（１） The delayed detection of the received signal will be described by taking the delayed detector 13 as an example. The received signal at the time t S (t), the amplitude of _{A t} of S phase of _{(t) θ t, S (} t), when the sampling interval is T, the delay of S (t) in the 1-sample delay unit 101 The signal obtained by detection is represented by the following equation (1).

・ ・ ・ Equation (1)

・・・ 式（２） The "x" in equation (1) means complex multiplication, and the superscript "*" means complex conjugate. Here, assuming that the phase error due to the frequency offset at the time t is φ _t , the delayed detection of the received signal including the frequency offset is expressed by the following equation (2).

・ ・ ・ Equation (2)

“Δφ _T ” in the equation (2) is the phase difference between the samples caused by the frequency offset. As is clear from the above two equations, if the frequency offset can be regarded as constant for a time corresponding to the reference signal length, the difference between the equation (1) and the equation (2) is only the phase offset. Therefore, it is possible to detect the signal detection / synchronization timing by obtaining the cross-correlation between the received signal subjected to the delayed detection and the reference signal subjected to the same delayed detection.

Here, in order to detect the received signal and the synchronization signal included in the received signal with high time accuracy, it is necessary to make the sample interval T sufficiently small (that is, make the sample rate sufficiently high). However, as the sample rate becomes higher than the modulation rate, the delayed-detected complex modulation signal is concentrated near 0 ° on the complex plane.

FIG. 5 is an example of a graph showing the amplitude of the complex signal output from the complex multiplier 102. In FIG. 5, the vertical axis represents amplitude and the horizontal axis represents time, both of which are arbitrary scales. FIG. 5 shows an example of the temporal variation of the amplitude of the complex signal output from the complex multiplier 102. If the received signal is a constant envelope signal, as shown in FIG. 5, the amplitude of the delayed detection result greatly exceeds the imaginary part in the absolute value of the real part having a small amplitude fluctuation. When the cross-correlation value between such signals is obtained, the real component having a small amplitude fluctuation becomes dominant in the calculation result of the cross-correlation value. As a result, a significant correlation peak may not be obtained. Therefore, as described above, it is difficult to detect synchronization with high time accuracy for a constant envelope signal by a general delayed detection method. Therefore, the delay detectors 12 and 13 of the present embodiment take out only the imaginary part of the reference signal and the received signal after the delayed detection by the imaginary part output device 103 and output them to the correlator 14.

Specifically, the imaginary part output device 103 outputs only the imaginary part of the delayed detection received signal represented by the equation (2) to the correlator 14. Similarly, for the reference signal, only the imaginary part of the delayed detected reference signal is output to the correlator 14. The correlator 14 calculates the cross-correlation value based only on the imaginary component input from the delay detectors 12 and 13. This makes it possible to easily detect a significant correlation peak (that is, signal detection / synchronization timing) at a high sample rate without being affected by the real component even for a received signal with a frequency offset. Become.

As described above, the receiver 100 of the first embodiment can perform signal detection and synchronous detection with high time accuracy even when receiving a constant envelope signal in an environment where a large frequency offset exists. The reason is that the influence of frequency offset is removed by delayed detection, the real part component is removed from the received signal and reference signal after delayed detection, and only the imaginary part component is used in the calculation of the cross-correlation value. This is because it is possible to calculate a highly effective cross-correlation value.

The signal detector 5 shown in FIG. 2 can be called a signal detection device. When the components of the signal detection device corresponding to FIG. 2 are described by adding parentheses to the reference code of the signal detector 5, the signal detection device includes a reference signal generation unit (11) and a first delay detection unit (12). ), A second delay detection unit (13), a correlation unit (14), and a determination unit (15).

The reference signal generation unit (11) generates a reference signal for detecting the correlation with the received signal. The first delayed detection unit (12) performs delayed detection by delaying the reference signal by one sample time, and outputs only the imaginary part component of the delayed detected reference signal. The second delayed detection unit (13) delays the received signal by one sample time to perform delayed detection, and outputs only the imaginary component of the delayed detected received signal. The correlation unit (14) obtains a cross-correlation value between the output of the first delay detection unit (12) and the output of the second delay detection unit (13). The determination unit (15) outputs a timing signal indicating the signal detection / synchronization timing based on the cross-correlation value.

The signal detection device having such a configuration removes the influence of the frequency offset by the delayed detection, and further, only the imaginary component of the received signal and the reference signal after the delayed detection is used for the calculation of the cross-correlation value. Therefore, this signal detection device also has the same effect as that of the first embodiment, that is, the peak of the significant correlation is easily detected at a high sample rate without being affected by the real part component.

(Second Embodiment)
FIG. 6 is a block diagram showing a configuration example of the receiver 200 according to the second embodiment of the present invention. The receiver 200 includes a signal detector 51 instead of the signal detector 5 as compared with the receiver 100 of the first embodiment. Since the functions of the antenna 1, the A / D (analog to digital) converter 2, the orthogonal detector 3, and the demodulator 4 included in the receiver 200 are the same as those of the receiver 100, these existing elements are the same. Names and reference numerals will be added, and duplicate explanations will be omitted as appropriate.

In the receiver 200, the A / D converter 2 converts the signal input from the antenna 1 into a digital signal and outputs the signal to the orthogonal detector 3. The orthogonal detector 3 detects the digital signal input from the A / D converter 2 and generates a received signal which is a complex signal. The received signal is output to the demodulator 4 and the signal detector 51.

The signal detector 51 generates a timing signal based on the complex signal generated by the orthogonal detector 3 and outputs it to the demodulator 4. The timing signal indicates the signal detection / synchronization timing in the demodulator 4. These timings are indicated, for example, by the rising edge of the timing signal, but the timings may be indicated by other means. A reception signal and a timing signal are input to the demodulator 4. The demodulator 4 demodulates the received signal, which is a complex signal, based on the timing indicated by the timing signal.

The configuration and operation of the signal detector 51 will be described below. FIG. 7 is a block diagram showing a configuration example of the signal detector 51. The signal detector 51 includes a reference signal generator 11, delay detectors 22 and 23, a correlator 24, and a determination device 15. The signal detector 51 is different from the signal detector 5 of the first embodiment in that the delay detectors 22 and 23 and the correlator 24 are provided instead of the delay detectors 12 and 13 and the correlator 14. To do. Unlike the delay detectors 12 and 13, the delay detectors 22 and 23 output a complex signal instead of an imaginary part signal. The correlator 24 calculates the cross-correlation value between the reference signal and the received signal based on the complex signals output from the delay detectors 22 and 23.

Also in this embodiment, the reference signal and the received signal are constant envelope signals. The reference signal generator 11 generates a reference signal and outputs it to the delay detector 22. The delay detector 22 delay-detects the reference signal and outputs the complex signal generated by the delay detection to the correlator 24. The delay detector 23 delay-detects the received signal output from the orthogonal detector 3 and outputs the complex signal generated by the delay detection to the correlator 24. The correlator 24 calculates the cross-correlation value between the complex signal output from the delay detector 22 and the complex signal output from the delay detector 23, and outputs the cross-correlation value to the determination device 15. The determination device 15 compares the cross-correlation value output from the correlator 24 with a preset threshold value, and determines signal detection or synchronization detection based on the comparison result. The determination result is output to the demodulator 4 of FIG. 6 as a timing signal. The determination device 15 has a function of detecting the peak of the cross-correlation value, and may output a timing signal when the peak exceeds the threshold value.

FIG. 8 is a block diagram showing the configurations of the delay detectors 22 and 23 of the second embodiment. Compared to the delay detectors 12 and 13 of the first embodiment, the delay detectors 22 and 23 include an N sample delay device 201 instead of the one sample delay device 101 and do not include an imaginary part output device 103. It differs in that. The delay detectors 22 and 23 have a similar configuration. That is, the delay detectors 22 and 23 include an N sample delayer 201 and a complex multiplier 102. A reference signal is input to the N sample delay device 201 and the complex multiplier 102 of the delay detector 22. A received signal is input to the N sample delay device 201 and the complex multiplier 102 of the delay detector 23. The N sample delayer 201 outputs a complex conjugate signal of a signal obtained by delaying the input signal (that is, the reference signal or the received signal) to the delay detectors 22 and 23 by N samples to the complex multiplier 102. N is an integer greater than or equal to 2.

The complex multiplier 102 complex-multiplies the input signal to the delay detector 22 or 23 and the complex conjugate signal of the output of the N sample delayer 201, and outputs the complex multiplication result. That is, the complex multiplier 102 of the delay detector 22 complex-multiplies the reference signal and the complex conjugate signal of the output of the N sample delayer 201, and outputs the result to the correlator 24. The complex multiplier 102 of the delay detector 23 complex-multiplies the received signal and the complex conjugate signal of the output of the N sample delayer 201, and outputs the result to the correlator 24.

Here, in the two delay detectors 22 and 23, N is set so that the product of the sample intervals T and N becomes a value close to the modulation cycle of the received signal (that is, TN ≈ modulation cycle). You may. By setting N to an integer greater than 2, the difference in sampling time between the two signals that are complexly multiplied during delayed detection increases, so even if the sample interval T is short, the complex signal obtained as a result of delayed detection is obtained. Is suppressed from concentrating near 0 ° on the complex plane. As a result, the peak of the correlation can be easily detected even when the cross-correlation is calculated by the complex signal at a high sample rate (= 1 / T) in the correlator 24. As the value of N is increased, the amount of delay required for the N sample delayer 201 also increases. This causes an increase in the circuit scale and an increase in cost of the N sample delayer 201. Therefore, for example, it is preferable to set N so that the product of T and N has a value at or near the modulation period. However, if the peak of the cross-correlation value between the complex signals is detected, the relationship required for T and N is not limited to this.

FIG. 9 is a flowchart showing an example of the operation procedure of the signal detector 51. As described above, the delay detector 22 and the delay detector 23 delay detection by delaying each of the reference signal and the received signal, which are complex signals, by N samples (step S11 in FIG. 9), and obtain the result as a complex. It is output to the correlator 24 as a signal (step S12). The correlator 24 calculates and outputs a cross-correlation value between the complex signal of the delayed-detected reference signal and the complex signal of the delayed-detected received signal (step S13). The determination device 15 has a function of detecting the peak of the cross-correlation value, and outputs the signal detection / synchronization timing based on the timing indicated by the peak of the cross-correlation value (step S14).

Similar to the signal detector 5 of the first embodiment, the function of the signal detector 51 may be realized by hardware, or may be realized by the CPU or DSP executing the program.

As described above, also in the receiver 200 of the second embodiment, the influence of the frequency offset can be canceled by the delayed detection, and the signal and the synchronous detection with high time accuracy can be performed. The reason is that the N sample delayer is used to perform delayed detection of the reference signal and the received signal, and the complex signal obtained as a result is used to detect the cross-correlation value. Further, the receiver 200 of the second embodiment calculates the cross-correlation value with high time accuracy even if a complex signal is used for the calculation of the cross-correlation value by setting the delay amount at the time of delay detection to N samples. can do.

The signal detector 51 shown in FIG. 7 can be called a signal detection device. When the components of the signal detection device corresponding to FIG. 7 are described by adding parentheses to the reference code of the signal detector 51, the signal detection device includes a reference signal generation unit (11) and a first delay detection unit ( 22), a second delay detection unit (23), a correlation unit (24), and a determination unit (25) are provided.

The reference signal generation unit (11) generates a reference signal for detecting the correlation with the received signal. The first delayed detection unit (22) delays the reference signal by N sample times, performs delayed detection, and outputs the delayed detected reference signal. The second delayed detection unit (23) delays the received signal by N sample times, performs delayed detection, and outputs the delayed detected received signal. Here, N is an integer of 2 or more. The correlation unit (24) obtains a cross-correlation value between the output of the first delay detection unit (22) and the output of the second delay detection unit (23). The determination unit (15) outputs a timing signal indicating the signal detection / synchronization timing based on the cross-correlation value.

A signal detection device having such a configuration also performs the second implementation by performing delayed detection of the reference signal and the received signal using the N sample delayer and obtaining the cross-correlation value using the complex signal obtained as a result. It has the same effect as the form.

The functions and procedures described in each of the above embodiments may be realized by the CPU included in the receivers 100 and 200 executing the program. The program is recorded on a fixed, non-temporary recording medium. A semiconductor memory or a fixed magnetic disk device is used as the recording medium, but the recording medium is not limited thereto. The CPU and the recording medium of the program may be provided in the signal detectors 5 and 51.

In addition, the embodiment of the present invention may be described as the following appendix, but is not limited thereto.

(Appendix 1)
A reference signal generator that generates a reference signal for detecting the correlation with the received signal,
A first delayed detection unit that delays the reference signal by one sample time to perform delayed detection and outputs only the imaginary component of the delayed detected reference signal.
A second delayed detection unit that delays the received signal by one sample time, performs delayed detection, and outputs only the imaginary component of the delayed detected received signal.
A correlation unit for obtaining a cross-correlation value between the output of the first delay detection unit and the output of the second delay detection unit, and
A determination unit that outputs a timing signal indicating at least one of the detection timing and the synchronization timing of the received signal based on the cross-correlation value, and a determination unit.
A signal detection device comprising.

(Appendix 2)
The signal detection device according to Appendix 1, wherein the reference signal and the received signal are constant envelope signals.

(Appendix 3)
The signal detection device according to Appendix 1 or 2, wherein the reference signal includes a synchronization signal of the received signal.

(Appendix 4)
The signal detection device according to Appendix 1, wherein the reference signal and the received signal are chirp signals.

(Appendix 5)
An A / D converter that converts the wireless signal received from the antenna into a digital signal,
An orthogonal detection unit that generates the received signal by orthogonally detecting the output of the A / D conversion unit, and
A demodulator that demolishes the received signal based on the timing signal and outputs the demolished signal,
The signal detection device according to any one of Appendix 1 to 4, wherein the received signal output from the orthogonal detection unit is input and the timing signal is output to the demodulation unit.
A receiver equipped with.

(Appendix 6)
Generate a reference signal to detect the correlation with the received signal
Delay detection is performed by delaying the reference signal by one sample time.
Only the imaginary component of the reference signal that has been delayed detected is output.
Delay detection is performed by delaying the received signal by one sample time.
Only the imaginary component of the received signal that has been delayed detected is output.
The cross-correlation value between the imaginary component of the delayed-detected reference signal and the imaginary component of the delayed-detected received signal was obtained.
A timing signal indicating at least one of the detection timing and the synchronization timing of the received signal is output based on the cross-correlation value.
Signal detection method.

(Appendix 7)
Converts wireless signals to digital signals
The digital signal is orthogonally detected to generate the received signal, and the received signal is generated.
The received signal is demodulated based on the timing signal and the demodulated signal is output.
Based on the received signal, the timing signal is output by the signal detection method described in Appendix 6.
Reception method.

(Appendix 8)
To the computer of the signal detector
Procedure for generating a reference signal to detect the correlation with the received signal,
Procedure for performing delayed detection by delaying the reference signal by one sample time,
Procedure for outputting only the imaginary component of the reference signal that has been delayed detected,
A procedure for delay detection by delaying the received signal by one sample time.
A procedure for outputting only the imaginary component of the received signal that has been delayed detected,
A procedure for obtaining a cross-correlation value between a delayed-detected imaginary part component of the reference signal and a delayed-detected imaginary part component of the received signal.
A procedure for outputting a timing signal indicating at least one of the detection timing and the synchronization timing of the received signal based on the cross-correlation value.
A signal detection program for executing.

(Appendix 9)
A reference signal generator that generates a reference signal for detecting the correlation with the received signal,
A first delayed detection unit that delays the reference signal by N (N is an integer of 2 or more) sample time to perform delayed detection and outputs the delayed detected reference signal.
A second delay detection unit that delays the received signal by N sample times, performs delayed detection, and outputs the delayed detected received signal.
A correlation unit for obtaining a cross-correlation value between the output of the first delay detection unit and the output of the second delay detection unit, and
A determination unit that outputs a timing signal indicating at least one of the detection timing and the synchronization timing of the received signal based on the cross-correlation value, and a determination unit.
A signal detection device comprising.

(Appendix 10)
The signal detection device according to Appendix 9, wherein the product of T and N is substantially equal to the modulation period of the reference signal and the received signal when the sampling interval of the reference signal and the received signal is T.

(Appendix 11)
The signal detection device according to Appendix 9 or 10, wherein the reference signal and the received signal are constant envelope signals.

(Appendix 12)
The signal detection device according to any one of Supplementary note 9 to 11, wherein the reference signal includes a synchronization signal of the received signal.

(Appendix 13)
The signal detection device according to Appendix 9 or 10, wherein the reference signal and the received signal are chirp signals.

(Appendix 14)
An A / D converter that converts the wireless signal received from the antenna into a digital signal,
An orthogonal detection unit that generates the received signal by orthogonally detecting the output of the A / D conversion unit, and
A demodulation unit that demodulates the received signal based on the timing signal and outputs the demodulated signal,
The signal detection device according to any one of Appendix 9 to 13, wherein the received signal output from the orthogonal detection unit is input and the timing signal is output to the demodulation unit.
A receiver equipped with.

(Appendix 15)
Generate a reference signal to detect the correlation with the received signal
Delay detection is performed by delaying the reference signal by N (N is an integer of 2 or more) sample time.
Delay detection is performed by delaying the received signal by N sample time, and then performing delay detection.
The cross-correlation value between the delayed-detected reference signal and the delayed-detected received signal was obtained.
A timing signal indicating at least one of the detection timing and the synchronization timing of the received signal is output based on the cross-correlation value.
Signal detection method.

(Appendix 16)
Converts wireless signals to digital signals
The digital signal is orthogonally detected to generate the received signal, and the received signal is generated.
The received signal is demodulated based on the timing signal and the demodulated signal is output.
Based on the received signal, the timing signal is output by the signal detection method described in Appendix 15.
Reception method.

(Appendix 17)
To the computer of the signal detector
Procedure for generating a reference signal to detect the correlation with the received signal,
A procedure for delay detection by delaying the reference signal by N (N is an integer of 2 or more) sample time.
Procedure for delay detection by delaying the received signal by N sample time,
Procedure for obtaining the cross-correlation value between the delayed-detected reference signal and the delayed-detected received signal,
A procedure for outputting a timing signal indicating at least one of the detection timing and the synchronization timing of the received signal based on the cross-correlation value.
A signal detection program for executing.

Although the present invention has been described above with reference to the embodiments, the present invention is not limited to the above embodiments. Various changes that can be understood by those skilled in the art can be made within the scope of the present invention in terms of the structure and details of the present invention.

Further, the configurations described in the respective embodiments are not necessarily exclusive to each other. The actions and effects of the present invention may be realized by a configuration in which all or a part of the above-described embodiments are combined.

1 Antenna 2 A / D converter 3 Orthogonal detector 4 Demodulator 5, 51 Signal detector 11 Reference signal generator 12, 13, 22, 23 Delay detector 14, 24 Correlator 15 Judge 100, 200 Receiver 101 1 sample delayer 102 complex multiplier 103 imaginary part output device 201 N sample delayer

Claims (8)

A reference signal generator that generates a reference signal for detecting the correlation with the received signal,
A first delay detection unit that delays the reference signal by one sample time, performs delayed detection, and outputs the delayed-detected reference signal.
A second delay detection unit that delays the received signal by one sample time, performs delayed detection, and outputs the delayed detected received signal.
A correlation unit for obtaining a cross-correlation value between only the imaginary part components of the output of the first delay detection unit and the output of the second delay detection unit, and
A determination unit that outputs a timing signal indicating at least one of the detection timing and the synchronization timing of the received signal based on the cross-correlation value, and a determination unit.
A signal detection device comprising. The signal detection device according to claim 1, wherein the reference signal and the received signal are constant envelope signals. The signal detection device according to claim 1 or 2, wherein the reference signal includes a synchronization signal of the received signal. The signal detection device according to claim 1, wherein the reference signal and the received signal are chirp signals. An A / D converter that converts the wireless signal received from the antenna into a digital signal,
An orthogonal detection unit that generates the received signal by orthogonally detecting the output of the A / D conversion unit, and
A demodulation unit that demodulates the received signal based on the timing signal and outputs the demodulated signal,
The signal detection device according to any one of claims 1 to 4, wherein the received signal output from the orthogonal detection unit is input and the timing signal is output to the demodulation unit.
A receiver equipped with. Generate a reference signal to detect the correlation with the received signal
Delay detection is performed by delaying the reference signal by one sample time.
Delay detection is performed by delaying the received signal by one sample time.
The cross-correlation value between only the imaginary components of the delayed-detected reference signal and the delayed-detected received signal was obtained.
A timing signal indicating at least one of the detection timing and the synchronization timing of the received signal is output based on the cross-correlation value.
Signal detection method. Converts wireless signals to digital signals
The digital signal is orthogonally detected to generate the received signal, and the received signal is generated.
The received signal is demodulated based on the timing signal and the demodulated signal is output.
Based on the received signal, the timing signal is output by the signal detection method according to claim 6 .
Reception method. To the computer of the signal detector
Procedure for generating a reference signal to detect the correlation with the received signal,
Procedure for performing delayed detection by delaying the reference signal by one sample time,
A procedure for delay detection by delaying the received signal by one sample time.
A procedure for obtaining a cross-correlation value between only the imaginary components of the delayed-detected reference signal and the delayed-detected received signal.
A procedure for outputting a timing signal indicating at least one of the detection timing and the synchronization timing of the received signal based on the cross-correlation value.
A signal detection program for executing.

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