A two-dimensional sliding window-based super-long link transmission parameter self-synchronization measurement method

Abstract

The application relates to a two-dimensional sliding window-based super-long link transmission parameter self-synchronization measurement method, which calculates the frequency scanning point number of a frequency scanning source and the frequency segment number of a receiver, sets the frequency scanning source to step and scan power according to a measurement frequency resolution, sets the receiver to wait in any segment, sequentially searches and finds the power of a test frequency point in the segment, switches the center frequency of a superheterodyne receiver when the frequency scanning of the frequency scanning source reaches the end frequency of the segment, sequentially searches and finds the power of all test frequency points in the next segment, and then returns to the first segment to cyclically and reciprocally measure until the scanning of all segments is completed. A transmission parameter measurement device of a long-distance communication link is constructed, step-by-step and autonomous scanning is performed in the frequency domain, a spectrum acquisition module slides in the frequency and time dimensions, the power levels of measurement signals in a frequency scanning band are self-synchronously detected, the accurate measurement of the full-band gain and the amplitude-frequency corresponding curve of a long-distance communication link is realized, and data support is provided for link self-checking and fault diagnosis.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of communication link online measurement, fault diagnosis and link optimization, and particularly relates to a two-dimensional sliding window-based super-long link transmission parameter self-synchronous measurement method. BACKGROUND

[0002] For parameter testing of an off-site super-long distance link, it is very complex to realize synchronous measurement, and generally only a non-synchronous mode of a split testing device can be adopted, the testing signal transmitting end device only needs to wait for time interval frequency step-by-step cyclic scanning, and the testing receiving end adopts superheterodyne reception to collect signals to do fast Fourier transform (FFT) to identify and calculate the frequency and power of the testing signal. For wideband spectrum collection, it needs to be collected in segments, and the superheterodyne mixing frequency cannot be synchronized with the testing signal. If it is required to ensure that the testing signal can be collected by the receiver scanning each time, the scanning time interval ΔT of the testing signal needs to be greater than the scanning time length T of the receiver. The receiver scans 1200MHz bandwidth according to the resolution of 1MHz, about 2 seconds, and the receiver needs to scan 1200 times for measurement once, a total of 2400 seconds (40 minutes). The full-band measurement refresh time is too long, and the measurement efficiency is too low, which cannot be accepted by the system.

[0003] Therefore, how to improve the existing full-band super-long link transmission parameter measurement method, avoid the large non-synchronous measurement error caused by the fact that the testing signal does not appear or is in the up / down rising edge state, reduce the full-band measurement refresh time, and improve the measurement efficiency are currently technical problems to be solved. SUMMARY

[0004] The purpose of the application is to provide a two-dimensional sliding window-based super-long link transmission parameter self-synchronous measurement method to solve the technical problems that the large non-synchronous measurement error is caused by the fact that the testing signal does not appear or is in the up / down rising edge state, the full-band measurement refresh time is too long, the measurement efficiency is too low, and the system cannot accept it.

[0005] To solve the above technical problems, the technical solution adopted by the application is as follows:

[0006] A two-dimensional sliding window-based super-long link transmission parameter self-synchronous measurement method, comprising the following steps:

[0007] S1: calculating the scanning frequency point number M of the frequency sweeping source and the frequency segment number N of the receiver;

[0008] S2: the frequency sweeping source scans according to the measurement frequency resolution step, and the receiver is set to wait in the first frequency segment;

[0009] S3: sequentially searching and finding the power of all testing frequencies in the frequency segment;

[0010] S4: Adopting frequency sliding window, tracking test frequency, switching receiver center frequency in turn.

[0011] Preferably, in step S1, the specific process of calculating the measured sweep source scanning frequency point number M and the frequency segment number N of the receiver is as follows:

[0012] ;

[0013] ;

[0014] Wherein, TRUNC(·) is the integer function, F start is the start frequency of measurement, F End is the end frequency of measurement, RBW is the frequency resolution of measurement, BW A / D is the real-time acquisition bandwidth of the receiver.

[0015] Preferably, in step S2, the specific process of setting the sweep source equal-power frequency scanning is as follows:

[0016] ;

[0017] ;

[0018] ;

[0019] ;

[0020] Wherein, F start is the start frequency of measurement, F scanstart is the start frequency of the sweep source, F scanEnd is the end frequency of the sweep source, F step is the frequency interval of the sweep source, RBW is the frequency resolution of measurement, T Scan is the total scanning time, R is the time length redundancy coefficient, T FFT is the 1st FFT sampling and calculation time, M is the total number of sweep frequency points;

[0021] The specific process of setting the receiver waiting frequency segment in step S2 is as follows:

[0022] The center frequency F Center (n) of the superheterodyne receiver is:

[0023] ;

[0024] Wherein, F start is the start frequency of measurement, n is the segment number, the value range is 0~N-1, N is the frequency segment number of the receiver, BW A / D is the real-time acquisition bandwidth of the receiver.

[0025] After starting the measurement, set n as 0, the center frequency of the receiver is:

[0026]

[0027] Preferably, in step S3, the time window is slid, the power level is collected, calculated and extracted by algorithm, and the specific process of searching for the power of the test frequency in turn is as follows:

[0028] The calculation formula of the test frequency F(m) is as follows:

[0029]

[0030] m is the serial number of the sweep frequency point, and the value range is 0~M-1, wherein M is the total number of sweep frequency points.

[0031] The receiver is in continuous signal collection, and the FPGA performs FFT operation according to the collection time. When the sweep source frequency F(m) is scanned to F0-BW A / D / 2~F Start + BW A / D / 2, the power P(m+1) of F(m+1) is detected in turn in the measurement segment until F(m) exceeds the range of (F0-BW A / D / 2)~(F Start + BW A / D / 2);

[0032] When the power P 检测 of the measurement frequency F(m) is much larger than the noise level, recorded as P(0), and the power P(i) of the measurement frequency F(m) is collected and FFT calculated for multiple times, until the P(I) of the Ith time is close to the noise level, and the measurement power value of the measurement frequency F(m) is:

[0033] , i=0,1,2,…,I;

[0034] Since the power of the sweep signal source at a certain frequency point is a short-time burst in time, and has a rising edge and a falling edge, from the appearance to the disappearance of the signal, in different FFT time windows, the detection spectrum power gradually increases, stabilizes, and then gradually decreases, and the power of the time window with stable power is selected as the measurement power.

[0035] Preferably, in step S4, the frequency sliding window is used to track the test frequency, and the center frequency of the receiver is switched in turn, and the specific process is as follows:

[0036] When it is detected that the next test signal frequency will exceed the real-time collection bandwidth or is greater than the measurement end frequency F End :

[0037] ​​ or

[0038] ;

[0039] Switching receiver center frequency is:

[0040] ;

[0041] Wherein:

[0042] .

[0043] m is the frequency point number of the sweep source, n is the receiver segment number, and N is the total number of receiver segments.

[0044] The beneficial effects of the present application include:

[0045] The two-dimensional sliding window-based super-long link transmission parameter self-synchronization measurement method provided by the present application first calculates the frequency point number of the sweep source and the frequency segment number of the receiver, then sets the sweep source to step power scanning according to the measurement frequency resolution, and sets the receiver to wait in the first segment. All test frequency points of the first segment are searched and found for power. When the frequency of the sweep source scans to the end frequency of the first segment, the center frequency of the superheterodyne receiver is switched, and all test frequency points of the next segment are searched and found for power in turn. Until the scanning of all segments is completed, the measurement is returned to the first segment and repeated. The sweep source, coupler and spectrum acquisition are used to construct a transmission parameter measurement device of a long-distance communication link, and the sweep source is used to step and scan autonomously in the frequency domain at equal time intervals. The spectrum acquisition module slides in the window with equal width in two dimensions of frequency and time, and the measurement signal power level in the sweep band is detected synchronously to realize accurate measurement of the full-band gain and amplitude-frequency response curve of the long-distance communication link, and to provide data support for link self-checking and fault diagnosis. BRIEF DESCRIPTION OF DRAWINGS

[0046] Figure 1 The flowchart of the two-dimensional sliding window-based super-long link transmission parameter self-synchronization measurement method of the present application.

[0047] Figure 2 The frequency-time two-dimensional sliding window diagram of the present application.

[0048] Figure 3 Another frequency-time two-dimensional sliding window diagram of the present application.

[0049] Figure 4 The detection signal power difference diagram of different acquisition time windows of the present application.

[0050] Figure 5 The detection signal amplitude difference diagram of different acquisition time windows of the present application. DETAILED DESCRIPTION

[0051] The application will be further described below in conjunction with the accompanying drawings Figures 1-5 The application will be further described below in conjunction with the accompanying drawings

[0052] Embodiment 1

[0053] Referring to the accompanying drawings Figure 1 As shown in the drawings, a two-dimensional sliding window-based super-long link transmission parameter self-synchronization measurement method comprises the following steps:

[0054] S1: calculating the frequency scanning point number M of the frequency sweep source and the frequency segment number N of the receiver;

[0055] S2: the frequency sweep source performs equal-power scanning according to the measurement frequency resolution step, and the receiver is set at the first waiting frequency segment;

[0056] S3: the power level is collected, calculated and extracted by algorithm by using time window sliding, and the powers of all test frequencies in the frequency segment are searched and found in turn;

[0057] S4: the test frequency is tracked by using the frequency sliding window, and the center frequency of the receiver is switched in turn.

[0058] First, the frequency scanning point number M of the frequency sweep source and the frequency segment number N of the receiver are calculated, then the frequency sweep source is set to perform equal-power scanning according to the measurement frequency resolution step, the receiver is set at the first waiting frequency segment, the powers of all test frequency points in the first segment are searched and found in turn, when the frequency of the frequency sweep source scans to the end frequency of the first segment, the center frequency of the superheterodyne receiver is switched, the powers of all test frequency points in the next segment are searched and found in turn, until the scanning of all segments ends, and then the measurement is performed in a loop back and forth between the first segment. The transmission parameter measurement device of the long-distance communication link is constructed by using the separated modules of the frequency sweep source, the coupler and the spectrum collection, the frequency sweep source is used to perform autonomous scanning in the frequency domain at a time interval, the spectrum collection module is used to slide in the frequency and time dimensions according to the window with equal width, the measurement signal power level in the frequency sweep band is self-synchronized and detected, and the accurate measurement of the full-band gain and the amplitude-frequency corresponding curve of the long-distance communication link is realized, thereby providing data support for the link self-check and fault diagnosis.

[0059] Embodiment 2

[0060] On the basis of embodiment 1, the specific process of calculating the frequency scanning point number M of the measurement frequency sweep source and the frequency segment number N of the receiver in step S1 is as follows:

[0061] ;

[0062] ;

[0063] wherein, TRUNC(·) is an integer function, Fstart Fstart is the start frequency of the measurement End Fend is the end frequency of the measurement, RBW is the frequency resolution of the measurement, BW is the real-time sampling bandwidth of the receiver A / D Fend is the end frequency of the measurement, RBW is the frequency resolution of the measurement, BW is the real-time sampling bandwidth of the receiver

[0064] If the measurement frequency range is 950MHz-2150MHz, the real-time sampling bandwidth of the receiver is 36MHz, and the measurement resolution is 1KHz, then:

[0065] ;

[0066] ;

[0067] On the basis of Embodiment 1, the specific process of setting the frequency sweep source parameters and the receiver in the first waiting frequency range in step S2 is as follows:

[0068] The scan frequency of the frequency sweep source is set as:

[0069] ;

[0070] ;

[0071] ;

[0072] ;

[0073] Fstart is the start frequency of the measurement start Fend is the end frequency of the measurement, RBW is the frequency resolution of the measurement, BW is the real-time sampling bandwidth of the receiver scanstart Fstart is the start frequency of the measurement scanEnd Fend is the end frequency of the measurement, RBW is the frequency resolution of the measurement, BW is the real-time sampling bandwidth of the receiver step Fend is the end frequency of the measurement, RBW is the frequency resolution of the measurement, BW is the real-time sampling bandwidth of the receiver Scan Fend is the end frequency of the measurement, RBW is the frequency resolution of the measurement, BW is the real-time sampling bandwidth of the receiver FFT Fend is the end frequency of the measurement, RBW is the frequency resolution of the measurement, BW is the real-time sampling bandwidth of the receiver

[0074] Fstart is the start frequency of the measurement start Fend is the end frequency of the measurement, RBW is the frequency resolution of the measurement, BW is the real-time sampling bandwidth of the receiver End Fend is the end frequency of the measurement, RBW is the frequency resolution of the measurement, BW is the real-time sampling bandwidth of the receiver A / D Fend is the end frequency of the measurement, RBW is the frequency resolution of the measurement, BW is the real-time sampling bandwidth of the receiver FFT Fend is the end frequency of the measurement, RBW is the frequency resolution of the measurement, BW is the real-time sampling bandwidth of the receiver

[0075] ;

[0076] ;

[0077] The center frequency of the receiver waiting frequency range is set, and the specific process is as follows:

[0078] ;

[0079] center frequency of superheterodyne receiver for:

[0080] .

[0081] Example 3

[0082] Based on Examples 1 and 2, in step S3, a time window sliding method is used to collect, calculate, and extract power levels using algorithms. The power of all test frequencies within the frequency band is then searched sequentially. The specific process is as follows:

[0083] The test frequency F(m) is:

[0084] ;

[0085] The first frequency F(0) tested is:

[0086] ;

[0087] The receiver is continuously acquiring signals, and the FPGA performs FFT operations in segments according to the acquisition time. When the frequency of the sweep source is F (m), it scans to F0-BW. A / D / 2~F Start + BW A / D Within a range of / 2, the power P(m+1) of F(m+1) is sequentially measured within the measurement segments until F(m) exceeds (F0-BW). A / D / 2~(F) Start + BW A / D Within the range of / 2.

[0088] When the detection power of the measurement frequency F (m) The value much greater than the noise level (e.g., setting the threshold as ΔP≥10dB) is denoted as P(0). Multiple data acquisitions and FFT calculations are then performed to obtain the power at the measured frequency F(m). Until the Ith When the noise level is close to the threshold (e.g., the threshold is set to ΔP ≤ 10 dB), the measured power value P(m) at the measurement frequency F(m) is:

[0089] , i=0,1,2,…,I.

[0090] Because the power of the sweep signal source at a certain frequency is a short burst in time, and has a rising edge and a falling edge, from the appearance to the disappearance of the signal, in different FFT time windows, the detection spectrum power gradually increases, stabilizes, and then gradually decreases, the power of the time window where the power is stable is selected as the power of this measurement.

[0091] The multiple detection powers P(i) are as follows:

[0092] Table 1: Continuous power detection result table

[0093]

[0094] It can be seen that, because the signal appears and disappears out of synchronization with the sampling time, the power values obtained by FFT calculation are quite different, the maximum value of P(i) is -20 dBm, and the value of P(m) obtained is stable.

[0095] Referring to Figs. 6 and 7, Figure 4 and Figure 5 It can be seen that, in the sampling time periods 3 and 7, because the on and off time of the large / small signal is different, the power accumulated by FFT is different, and the difference is large. In the remaining sampling time periods, because the signal is not switched, the power accumulated by FFT is stable and unchanged.

[0096] On the basis of Embodiment 1 and Embodiment 2, in step S4, a frequency sliding window is used to track the test frequency, and the receiver center frequency is switched in turn, and the specific process is as follows:

[0097] When it is detected that the next test signal frequency will exceed the real-time acquisition bandwidth or be greater than the measurement end frequency:

[0098] or

[0099] .

[0100] The receiver center frequency is switched to:

[0101] .

[0102] Wherein:

[0103] .

[0104] Wherein, m is the sweep frequency point number, n is the receiver segment number, M is the total number of sweep frequency points, and N is the total number of receiver segments.

[0105] Referring to Figs. 6 and 7, Figure 2 and Figure 3As shown, F(m) in the figure is the signal scanning frequency, unit is MHz, m ranges from 0 to M-1, Fc(n) is the receiving center frequency, n ranges from 0 to M-1, m is the scanning frequency point serial number, n is the receiver segmentation serial number, M is the total number of scanning frequency points, N is the total number of receiver segments, △T is the sampling+FFT time interval. Time is sliding in the time domain according to the △T time window, and for the signal scanning frequency F(m) and the receiving center frequency Fc(n), the frequency is sliding in the frequency domain according to the resolution bandwidth RBW and the receiver A / D sampling bandwidth BW A / D .

[0106] In summary, the two-dimensional sliding window-based super-long link transmission parameter self-synchronization measurement method provided by the application first calculates the scanning frequency point number of the frequency scanning source and the frequency segmentation number of the receiver, then sets the frequency scanning source to step power scanning according to the measurement frequency resolution, and sets the receiver to wait in any segment, searches and finds the power of all test frequency points in the segment in turn, when the frequency scanning of the frequency scanning source reaches the end frequency of the segment, switches the superheterodyne receiver center frequency, searches and finds the power of all test frequency points in the next segment in turn, until all segment scanning ends, and then returns to the first segment, and the measurement is carried out in a cycle. The transmission parameter measurement device of the off-site super-long communication link is constructed by using the frequency scanning source, the coupler and the spectrum acquisition and other separated modules, the frequency scanning source is used to step and autonomously scan in the frequency domain at a time interval, the spectrum acquisition module is used to slide in the frequency and time two dimensions according to the window with equal width, the power level of the measurement signal in the frequency scanning band is self-synchronized and detected, the full-band gain and the amplitude-frequency corresponding curve of the off-site super-long distance communication link are accurately measured, and data support is provided for the link self-checking and fault diagnosis.

Claims

1. A method for measuring synchronization of transmission parameters of an ultra-long link based on a two-dimensional sliding window, characterized in that, The method comprises the following steps: S1: calculating the frequency scanning point number M of the sweep source and the frequency segment number N of the receiver; S2: the sweep source performs equal-power scanning according to the measurement frequency resolution step, and the receiver is set to wait in the first frequency segment; S3: all the powers of the test frequencies in the frequency segment are searched and found in sequence; S4: a frequency sliding window is adopted to track the test frequencies, and the center frequency of the receiver is switched in sequence; In step S1, the specific process of calculating the measurement sweep source scanning frequency point number M and the frequency segment number N of the receiver is as follows: ； ； wherein TRUNC(·) is a rounding function, F start is the start frequency of the measurement, F End is the end frequency of the measurement, RBW is the frequency resolution of the measurement, BW A / D is the receiver real-time acquisition bandwidth; The specific process of setting the sweep source equal-power frequency scanning in step S2 is as follows: ； ； ； ； where F start is the start frequency of the measurement, F scanstart is the start frequency of the sweep source, F scanEnd is the end frequency of the sweep source, F step is the frequency interval of the sweep source, RBW is the frequency resolution of the measurement, T Scan is the total time of the scan, R is the time length redundancy factor, T FFT is the 1st FFT sampling and calculation time, M is the total number of sweep points; The specific process of setting the receiver to wait in the frequency segment in step S2 is as follows: The center frequency F of a superheterodyne receiver Center (n) is: ； Wherein, F start is the measurement starting frequency, n is the segment number, the value range is 0~N-1, N is the frequency segment number of the receiver, BW A / D is the real-time acquisition bandwidth of the receiver; After starting the measurement, set n to 0, the receiver center frequency is: ； In step S3, the specific process of searching and finding the power of the test frequencies in sequence by adopting the time window sliding, collecting and calculating, and algorithm extracting the power level is as follows: The calculation formula of the test frequency F(m) is as follows: ； m is the sweep frequency point serial number, and the value range is 0-M-1, and M is the total number of sweep frequency points; The receiver is in continuous signal acquisition, FPGA is segmented by acquisition time to carry out FFT operation, when the frequency F(m) of the sweep source is scanned to F0-BW A / D / 2~F Start + BW A / D / 2 range, in the measurement segment, the power P(m+1) of F(m+1) is detected in turn until F(m) is out of the range of (F0-BW A / D / 2)~(F Start + BW A / D / 2); When measuring the power P of the frequency F(m) 检测 Much greater than the noise level, denoted P(0), and then collected and FFT calculated multiple times, the power P(i) of the measurement frequency F(m) is obtained, until the Ith P(I) is close to the noise level, and the measured power value of the measurement frequency F(m) is: , i = 0, 1, 2,..., I; Since the power of the sweep signal source at a frequency point is a short-time burst in time, and has a rising edge and a falling edge, from the appearance to the disappearance of the signal, the detection spectrum power gradually increases, stabilizes, and then gradually decreases in different FFT time windows, the power of the time window in which the power is stable is selected as the power of this measurement; In step S4, the specific process of adopting the frequency sliding window to track the test frequencies and switching the center frequency of the receiver in sequence is as follows: When it is detected that the next test signal frequency is about to exceed the real-time acquisition bandwidth or is greater than the measurement end frequency F End : or ； The center frequency of the receiver is switched as follows: ； Wherein: ； m is the sweep frequency point serial number, n is the receiver segment serial number, and N is the total number of receiver segments.

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