Multi-dimensional multi-channel broadband signal monitoring platform and amplitude phase testing method

Abstract

The invention belongs to the technical field of electromagnetic signal monitoring and analysis, and particularly relates to a multi-dimensional multi-channel broadband signal monitoring platform and an amplitude phase testing method.The monitoring platform is composed of a plurality of eight-channel receiving single machines, eight receiving single machines serve as a group, and any one of the eight receiving single machines serves as a basic function single machine in each group; a synchronous reference signal is generated through a parallel synchronous reference correction processor built in each functional single machine, and n * 8 parallel signals are received. The amplitude and phase test method comprises a frequency domain amplitude and phase consistency test and a time domain amplitude and phase consistency test. According to the invention, a synchronization reference rule correction processing mechanism and a frequency, amplitude and phase correction module are constructed, so that the technical problems that a long-term stability synchronization test cannot be realized only by adopting a step-by-step single-channel test in a traditional test, radio frequency phase shift introduced by a multi-channel synchronization test is inconsistent with an acquisition time sequence and the like are solved; and the signal parallel receiving and consistency analysis capabilities of 8 * n channels are realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of electromagnetic signal monitoring and analysis, and in particular relates to a multi-dimensional multi-channel broadband signal monitoring platform and an amplitude and phase testing method. Background Art

[0002] With the widespread application of various new technologies such as digital beam forming (DBF), multiple-input multiple-output (MIMO), and integrated RF in information equipment, the scale and complexity of the corresponding equipment have also increased significantly. There are more and more transmitting and receiving units, the signal bandwidth is getting wider, the data transmission rate is getting higher, and the control timing is becoming more and more complex. In recent years, a large number of large-scale equipment with multiple transmitting and receiving channels have been put into practical use.

[0003] At present, multi-channel transceiver equipment needs to focus on solving related technical problems such as accurately testing the amplitude and phase consistency change parameters of related channels and calibrating compensation under the real operating environment of rated power, pulse modulation, and multi-channel synchronous transmission. At present, there is a serious lack of relevant multi-channel parallel testing methods, and most of them use the single-channel successive testing method, which has low testing efficiency and complicated testing steps.

[0004] As a radio frequency electronic measurement instrument, the multi-dimensional multi-channel signal monitoring platform is mainly used to solve the problem of high-precision synchronous acquisition and analysis of multi-dimensional, multi-channel, and large-bandwidth electromagnetic signals, and to meet the test requirements of the amplitude and phase consistency of multi-channel radio frequency signals in multi-transceiver channel devices. At present, the most widely used multi-dimensional multi-channel signal monitoring platform on the market is a multi-channel digital receiver or a multi-channel receiving system. The multi-channel digital receiver is mainly a multi-channel parallel acquisition device, which mainly realizes the parallel acquisition of signals in the intermediate frequency band. It does not have a multi-channel radio frequency receiving front end or can only receive single-channel radio frequency. After the intermediate frequency power is divided into multiple paths, multi-channel signals can be acquired in parallel. The multi-channel receiving system is implemented by combining multiple modules of multiple types or multiple sets of equipment. It lacks a coordination and processing mechanism for parallel reception and parallel acquisition, and the equipment is not highly integrated, making it inconvenient to use. Summary of the invention

[0005] In view of the various deficiencies in the prior art, the inventors have researched and designed a multi-dimensional, multi-channel, broadband signal monitoring platform and an amplitude and phase testing method in long-term practice.

[0006] The present invention provides a multi-dimensional multi-channel broadband signal monitoring platform, which is composed of multiple 8-channel receiving units, with 8 units forming a group to form n groups. Each group uses any 8-channel receiving unit as a basic functional unit. A synchronous reference signal is generated by a parallel synchronous reference correction processor built into each functional unit, and multi-channel cascade correction processing is adopted to receive n*8 parallel signals.

[0007] The 8-channel receiving unit includes a signal receiving unit, a signal acquisition processing unit, a data analysis processing unit, a synchronization reference processing unit, a frequency synthesis unit, an auxiliary control unit and a power supply unit.

[0008] The synchronization reference processing unit includes a reference generator, a synchronization reference rule corrector, an external synchronization reference distributor and an internal synchronization reference distributor.

[0009] The reference generator generates a whole-machine synchronous reference signal, which is the reference for consistency testing of each group of multiple channels.

[0010] After the synchronization reference rule corrector corrects the synchronization reference signal, it is distributed into two paths after frequency domain consistency and time domain consistency correction, one path is used by the external synchronization reference distributor, and the other path is used by the internal synchronization reference distributor.

[0011] The external synchronization reference distributor receives the synchronization reference signal after regular correction and distributes it into 8 channels, which can synchronize 8 external 8-channel receiving units.

[0012] The internal synchronization reference distributor generates synchronization signals for internal 8-channel parallel sampling, and outputs 16 internal synchronization signals, which are 8 broadband synchronization signals and 8 narrowband synchronization signals.

[0013] Furthermore, the signal receiving unit is composed of 8 sets of radio frequency conversion conditioning modules, and the signal processing unit is composed of 8 sets of acquisition modules. The signal receiving unit and the signal processing unit receive electromagnetic signals and convert them into digital signals.

[0014] Furthermore, the signal receiving unit is a receiver front end, including a selection switch, a gain control, a preselector, a multi-stage mixer, a switch-combining amplifier, a filter and an intermediate frequency conditioning. The selection switch is used to switch between the RF input signal and the calibration signal. The gain control includes two circuits, a variable attenuator and a switch amplifier, to control the overall gain of the path signal. The preselector suppresses non-in-band signals according to the frequency characteristic parameters of the signal to be tested, and reduces the noise and non-correlated signals entering the receiving channel. The multi-stage mixer filter is used to down-convert or up-convert high-frequency signals or low-frequency signals so that the signal frequency band is moved to the frequency band directly quantized by the analog-to-digital converter. The switch-combining amplifier is used to combine the intermediate frequencies generated by the combination of multiple mixers and filters to achieve unified back-end processing. The filter performs broadband filtering and narrowband filtering respectively according to the needs of back-end signal acquisition. The intermediate frequency conditioning is divided into broadband level conditioning and narrowband conditioning. The broadband level conditioning adjusts the intermediate frequency signal level to the optimal acquisition area of ​​the broadband analog-to-digital converter; the narrowband conditioning performs an additional down-conversion on the intermediate frequency signal compared to broadband acquisition, reducing it to the acquisition range of the narrowband analog-to-digital converter.

[0015] Furthermore, the signal acquisition and processing unit is the digital-to-analog conversion part of the receiver, which is divided into two paths: broadband and narrowband. The signal acquisition and processing unit includes an analog-to-digital converter, a digital down-conversion and data interaction processing. The analog-to-digital converter includes a broadband analog-to-digital converter and a narrowband analog-to-digital converter, which respectively receive the broadband intermediate frequency signal and the narrowband intermediate frequency signal from the signal receiving unit, and perform broadband analog-to-digital conversion and narrowband analog-to-digital conversion to generate an intermediate frequency digital signal. The digital down-conversion includes broadband digital down-conversion and narrowband digital down-conversion, which multiplies the intermediate frequency digital signal with a complex exponential signal with the same intermediate frequency, and down-converts the passband signal to baseband. The data interaction processing of the signal acquisition and processing unit further integrates the broadband baseband data and the narrowband baseband data after digital down-conversion and decimation filtering, and performs transmission logic conversion to form a unified baseband data.

[0016] Further, the data analysis and processing unit receives the extracted filtered baseband data, classifies it into two parts, broadband data and narrowband data, through the data bus, and further performs frequency domain data processing and time domain data processing. The data analysis and processing unit includes frequency domain data processing, time domain data processing and consistency analysis. The frequency domain data processing includes a narrowband frequency domain data processor and a broadband frequency domain data processor, which receives the data from the signal acquisition and processing unit after down-conversion and extraction and filtering, and performs broadband signal frequency domain processing and narrowband signal frequency domain processing respectively. The time domain data processing includes narrowband time domain data processing and broadband time domain data processing, which receives the data from the signal acquisition and processing unit after down-conversion and extraction and filtering, and performs broadband signal time domain processing and narrowband signal time domain processing respectively. The consistency analysis includes frequency domain consistency analysis and time domain consistency analysis; the frequency domain consistency analysis receives narrowband frequency domain data and broadband frequency domain data, performs consistency analysis on the data within the set bandwidth of multiple channels with any channel as the reference channel, obtains the corresponding array relationship of frequency-channel-jitter and reports the test results. The time domain consistency analysis receives narrowband time domain data and broadband time domain data, performs consistency analysis on data within a time period determined by multiple channels using any channel as a reference channel, obtains a corresponding array relationship of time-channel-jitter and reports the test result.

[0017] Furthermore, the frequency synthesis unit generates a unified clock reference through an internal clock reference based on the reference signal, and distributes it to 8 types of signal generators respectively, thereby generating a calibration signal, 3 frequency-converting local oscillator signals and 3 fixed local oscillator signals.

[0018] Furthermore, the auxiliary control unit includes a main control module, an interface module and a baseboard. The power supply unit realizes AC / DC conversion and provides a multi-channel DC power supply function. The power supply unit includes an input filter, a PFC circuit, a DC / DC module, a current equalization circuit and an output filter circuit.

[0019] The present invention also provides an amplitude phase consistency test method, including a frequency domain amplitude phase consistency test and a time domain amplitude phase consistency test, wherein the time domain amplitude phase consistency test includes the following three steps:

[0020] a. First, set the receiver to the time domain receiving mode. According to the frequency band, bandwidth, peak power and number of channels of the tested signal, set the relevant parameters of the multi-dimensional multi-channel signal monitoring platform. The frequency band and bandwidth are set to the receiver center frequency and measurement bandwidth respectively, the peak power is set to the receiver reference level, and the number of channels is set to the receiver receiving channel.

[0021] b. Start the receiver test task, configure any channel as the reference channel, and enable the cursor value. At this time, the time values ​​of all receiving channels at this cursor point can be displayed accordingly.

[0022] c. Calculate the amplitude difference and phase difference.

[0023] Furthermore, the frequency domain amplitude phase consistency test includes the following two steps:

[0024] Step 1: Set up the receiver, including the following sub-steps:

[0025] Step S11: Initialize the receiver, start the test person, and call the channel calibration compensation data.

[0026] Step S12: Set the receiver to the frequency domain receiving mode, and set the relevant parameters of the multi-dimensional multi-channel signal monitoring platform according to the frequency band, bandwidth, peak power and number of channels of the tested signal. Among them, the frequency band and bandwidth are set to the center frequency and bandwidth of the receiver respectively, and the bandwidth also determines the measurement bandwidth of the receiver. The peak power is set to the reference level of the receiver, and the number of channels is set to the receiving channel of the receiver.

[0027] Step S13: Start the receiver test task, configure any channel as a reference channel, select a cursor value in any receiving spectrum of the corresponding receiver, and then the frequency values ​​of all receiving channels at this cursor point can be displayed.

[0028] Step 2: Calculate the amplitude difference and phase difference.

[0029] Furthermore, in the frequency domain amplitude phase consistency test and the time domain amplitude phase consistency test, the specific method for calculating the amplitude difference and the phase difference is:

[0030] Step S21: Based on the complex value obtained after the signal is digitally quantized, the amplitude difference of each channel (i=1:7) relative to the reference channel (i=0) can be calculated according to the following formula:

[0031] ;

[0032] Among them, A i is the amplitude difference in dB.

[0033] i is the channel number, specified by the receiver configuration.

[0034] I i It is the in-phase component of the complex value after the signal is quantized.

[0035] Q i It is the orthogonal component of the complex value after the signal is quantized.

[0036] Step S22: Based on the complex value obtained after the signal is digitally quantized, the phase difference of each channel relative to the reference channel (i=0) can be calculated according to the following formula:

[0037] ;

[0038] Among them, φ i is the phase difference in degrees (º).

[0039] i is the channel number, specified by the receiver configuration.

[0040] I i It is the in-phase component of the complex value after the signal is quantized.

[0041] Q i It is the orthogonal component of the complex value after the signal is quantized.

[0042] Step S23: By moving the cursor arbitrarily, the frequency of any frequency point within the bandwidth can be obtained. By repeating the calculation method above, the amplitude difference and phase difference of all frequency points can be obtained.

[0043] Step S24: Count the maximum amplitude difference A of all frequency points max , minimum value A min , the maximum phase difference φ max , minimum value φ min The amplitude consistency A and phase consistency φ of the received signals of the corresponding number of channels are calculated according to the following two formulas respectively.

[0044] ;

[0045] .

[0046] The beneficial effects of the present invention are:

[0047] 1) The synchronization reference processing unit has a synchronization reference rule correction processing mechanism, a built-in calibration module with adjustable frequency and amplitude, and a calibration test method with automatic switch switching. Through a dedicated synchronization calibration rule processor, the amplitude and phase offset between channels are calibrated and corrected, solving the problems of RF phase shift and acquisition timing inconsistency introduced by multi-channel synchronization testing, and maintaining a high amplitude and phase consistency measurement accuracy. At the same time, it has an external synchronization reference generation and distribution designed for extended channel testing, realizing the signal parallel reception capability of 8*n channels.

[0048] 2) Parallel 8-channel signal amplitude and phase consistency test, with built-in high-precision synchronization reference processing and precise data analysis and processing unit, has ultra-high acquisition timing phase consistency, which solves the problem that the current traditional test can only use step-by-step single-channel testing, multiple connections introduce additional measurement errors, and cannot achieve long-term stability testing. The number of parallel test channels is increased from single channel to 8*n channels. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 It is a functional block diagram of the multi-dimensional multi-channel signal monitoring platform of the present invention;

[0050] Figure 2 is a functional block diagram of a signal receiving unit of the present invention;

[0051] Figure 3 It is a functional block diagram of the signal acquisition and processing unit of the present invention;

[0052] Figure 4 is a functional block diagram of a data analysis and processing unit of the present invention;

[0053] Figure 5 is a functional block diagram of a synchronization reference processing unit of the present invention;

[0054] Figure 6 is a functional block diagram of a frequency synthesis unit of the present invention;

[0055] Figure 7 is a functional block diagram of the auxiliary control unit of the present invention;

[0056] Figure 8 is a functional block diagram of a power supply unit of the present invention;

[0057] Fig. 9 It is a functional block diagram of the 8*n channel receiving system of the present invention. DETAILED DESCRIPTION

[0058] The present invention will be further described in detail below in conjunction with the accompanying drawings and implementation examples. These implementation examples are described in sufficient detail so that those skilled in the art can understand and practice the present invention. Without departing from the spirit and scope of the present invention, logical, achievable and other changes may be made to the implementation. Therefore, the following detailed description should not be construed as limiting, and the scope of the present invention is limited only by the claims.

[0059] See also Figure 1 to Figure 8 A multi-dimensional multi-channel broadband signal monitoring platform of the present invention is composed of multiple 8-channel receiving units, which are grouped into n groups with 8 units. Each group uses any 8-channel receiving unit as a basic functional unit. A synchronization reference signal is generated by a parallel synchronization correction rule processor built into each functional unit. Multi-channel cascade correction processing is adopted to combine multiple basic functional units to expand the number of receiving channels and receive n*8 parallel signals. Due to the internal synchronization calibration of the unit and the synchronization correction between units, the combination realizes multi-channel synchronous reception with high synchronization accuracy and amplitude phase consistency.

[0060] The 8-channel receiving unit is used as the basic unit for testing. It includes six functional units, namely signal receiving unit 1, signal acquisition processing unit 2, data analysis processing unit 3, synchronization reference processing unit 4, frequency synthesis unit 5, auxiliary control unit 6 and power supply unit 7. The functional block diagram of the whole unit is shown in the figure. Figure 1 shown.

[0061] The signal receiving unit 1 is composed of 8 sets of RF frequency conversion conditioning modules, and the signal processing unit 2 is composed of 8 sets of acquisition modules. The signal receiving unit 1 and the signal processing unit 2 receive electromagnetic signals and convert them into digital signals. The digital signals enter the data bus after data interaction and further perform broadband and narrowband data processing according to the frequency domain and time domain respectively. Finally, the amplitude and phase consistency analysis of the frequency domain and time domain is performed and the results are reported.

[0062] See also Figure 2 The signal receiving unit 1 is the front end of the receiver, which converts the RF signal into an intermediate frequency signal. It includes six parts, namely, the selection switch 1-1, the gain control 1-2, the preselector 1-3, the multi-stage mixer 1-4, the switch amplifier 1-5, the filter 1-6 and the intermediate frequency conditioning 1-7, which together form a frequency conversion receiving channel. The output of two intermediate frequency signals is respectively for different application requirements, namely, broadband intermediate frequency and narrowband intermediate frequency. The broadband intermediate frequency is mainly used for the test requirements of broadband radar signals, and the narrowband intermediate frequency is mainly used for the test requirements of position communication signals. Compared with the broadband intermediate frequency, the narrowband intermediate frequency has an additional frequency conversion channel.

[0063] The selection switch 1-1 is used to switch between the RF input signal and the calibration signal. Through the built-in switch selection, the channel is calibrated in real time to ensure high amplitude and phase consistency during the test.

[0064] Gain control 1-2 includes two circuits, a variable attenuator and a switching amplifier, to achieve control of the overall gain of the channel signal. The input signal enters the variable attenuator and the switching amplifier in turn. The attenuation of the attenuator can be optimized and adjusted according to the signal amplitude to achieve the ability to test high-power signals. Changing the gain of the switching amplifier can improve the measurement capability of weak signals and comprehensively expand the measurement range of the signal amplitude of the multi-dimensional multi-channel signal monitoring platform.

[0065] The preselector 1-3 suppresses the out-of-band signal according to the frequency characteristic parameters of the signal to be tested, reduces the noise and non-correlated signals entering the receiving channel, and thus reduces the introduced test error. The preselector 1-3 can be configured as a plurality of different preselector components according to the signal receiving bandwidth and out-of-band suppression requirements. Figure 2 Only three groups of preselectors are shown.

[0066] The multi-stage mixer filter 1-4 is used to down-convert or up-convert a high-frequency signal or a low-frequency signal to move the signal frequency band to a frequency band that can be directly quantized by an analog-to-digital converter. Different signals are divided into multiple mixer and filter combinations using different local oscillators and intermediate frequency points according to the image frequency suppression algorithm and the difficulty of technical implementation. The multi-stage mixer filter 1-4 can be configured as a combination of multiple different mixers and filters according to the signal reception bandwidth and intermediate frequency bandwidth requirements. Figure 2 Only three groups of mixing filters are shown.

[0067] The switch combining amplifier 1-5 is used to combine the intermediate frequencies generated by multiple mixers and filters to achieve unified back-end processing. Filters 1-6 perform broadband filtering and narrowband filtering according to the needs of back-end signal acquisition. The intermediate frequency conditioning 1-7 is divided into broadband level conditioning and narrowband conditioning. The broadband level conditioning adjusts the intermediate frequency signal level to the optimal acquisition area of ​​the broadband analog-to-digital converter; the narrowband conditioning performs an additional down-conversion on the intermediate frequency signal compared to broadband acquisition, reducing it to the acquisition range of the narrowband analog-to-digital converter, thereby achieving the purpose of increasing the number of sampling bits.

[0068] See also Figure 3 The signal acquisition and processing unit 2 is the digital-to-analog conversion part of the receiver, which is divided into two paths, broadband and narrowband, and interactively processes the relevant data. The signal acquisition and processing unit 2 includes four parts, namely, analog-to-digital converter 2-1, digital down-conversion 2-2 and data interactive processing 2-3.

[0069] The analog-to-digital converter 2-1 consists of two parts, namely a broadband analog-to-digital converter 2-1-1 and a narrowband analog-to-digital converter 2-1-2, which respectively receive the broadband intermediate frequency signal and the narrowband intermediate frequency signal from the signal receiving unit 1, and perform broadband analog-to-digital conversion and narrowband analog-to-digital conversion respectively to generate an intermediate frequency digital signal representing the signal characteristics.

[0070] Digital down-conversion 2-2 refers to digital down-conversion and decimation filtering. Digital down-conversion 2-2 includes two parts: broadband digital down-conversion 2-2-1 and narrowband digital down-conversion 2-2-2. The intermediate frequency digital signal is multiplied by a complex exponential signal with the same intermediate frequency, and the passband signal is down-converted to baseband. At this time, the data sampling rate is very high and the processing calculation amount is very large. A low-pass filter is further used for decimation filtering to reduce the amount of data calculation.

[0071] The data interaction processing 2-3 of the signal acquisition processing unit further integrates the broadband baseband data and the narrowband baseband data after digital down-conversion and extraction filtering, and performs transmission logic conversion to form a unified baseband data.

[0072] See also Figure 4 The data analysis and processing unit 3 receives the extracted and filtered baseband data, and classifies it into broadband data and narrowband data through the data bus, and further performs frequency domain data processing and time domain data processing, and selects any channel as the reference channel. The acquired data is respectively subjected to frequency domain signal feature consistency analysis and time domain adjustment consistency analysis, and the test analysis results are reported and displayed. The data analysis and processing unit 3 includes three parts: frequency domain data processing 3-1, time domain data processing 3-2 and consistency analysis 3-3.

[0073] The frequency domain data processing 3-1 includes a narrowband frequency domain data processor 3-1-1 and a wideband frequency domain data processor 3-1-2. The data is received from the signal acquisition processing unit 2 after down-conversion and extraction and filtering, and the wideband signal frequency domain processing and narrowband signal frequency domain processing are performed according to the signal type and the set bandwidth, including functions such as frequency correction filtering, logarithmic operation and parallel detection.

[0074] The time domain data processing 3-2 includes narrowband time domain data processing 3-2-1 and broadband time domain data processing 3-2-2. The data after down-conversion and extraction and filtering are received from the signal acquisition processing unit 2, and broadband signal time domain processing and narrowband signal time domain processing are performed respectively according to the signal type and the set bandwidth, including functions such as time domain correction filtering and parallel detection.

[0075] Consistency analysis 3-3 includes frequency domain consistency analysis 3-3-1 and time domain consistency analysis 3-3-2. Frequency domain consistency analysis 3-3-1 receives narrowband frequency domain data and broadband frequency domain data, and uses any channel as a reference channel to perform consistency analysis on the data within the set bandwidth of multiple channels, obtains the corresponding array relationship of frequency-channel-jitter, and reports the test results. Time domain consistency analysis 3-3-2 receives narrowband time domain data and broadband time domain data, and uses any channel as a reference channel to perform consistency analysis on the data within a determined time period of multiple channels, obtains the corresponding array relationship of time-channel-jitter, and reports the test results.

[0076] See also Figure 5 The synchronization reference processing unit 4 is the core key unit of the present invention, and is composed of 4 parts, namely, a reference generator 4-1, a synchronization reference rule corrector 4-2, an external synchronization reference distributor 4-3 and an internal synchronization reference distributor 4-4. With a reference generator, an external synchronization reference input can also be used as a unified reference to generate a synchronization reference signal that is corrected by the frequency domain consistency and time domain consistency references and then distributed into two paths, respectively generating synchronization signals for the 8 channels inside the machine and generating external synchronization reference outputs for 8 external 8-channel receiving units.

[0077] The reference generator 4 - 1 generates a whole-machine synchronization reference signal, which is the reference for the consistency test of multiple channels of each group of 8-channel receiving units.

[0078] After the synchronization reference rule corrector 4-2 corrects the synchronization reference signal, it is distributed into two paths after frequency domain consistency and time domain consistency correction, one for the external synchronization reference distributor 4-3 and the other for the internal synchronization reference distributor 4-4.

[0079] The external synchronization reference distributor 4-3 synchronization reference signal is distributed into 8 channels after regular correction, which can synchronize 8 external 8-channel receiving units.

[0080] The internal synchronization reference distributor 4-4 is used for the synchronization signal during the internal 8-channel parallel sampling. Since it involves broadband sampling and narrowband sampling, the internal synchronization reference distributor 4-4 outputs 16 internal synchronization signals, including 8 broadband synchronization signals and 8 narrowband synchronization signals.

[0081] See also Figure 6 The frequency synthesis unit 5 generates a unified clock reference based on the reference signal through the internal clock reference, and distributes it to 8 types of signal generators to generate a calibration signal, a variable frequency local oscillator 1 (LOHP1), a variable frequency local oscillator 2 (LOHP2), a variable frequency local oscillator 3 (LOHP3), a fixed local oscillator 1 (LOFP1), a fixed local oscillator 2 (LOFP2) and a fixed local oscillator 3 (LOFP3).

[0082] Among them, the calibration signal generates 8 signals with variable frequency, consistent phase and amplitude, which are cut into the RF frequency conversion conditioning module through a switch to be used for unified calibration of the amplitude and phase of the internal 8 receiving channels.

[0083] Variable frequency local oscillator 1 (LOHP1), variable frequency local oscillator 2 (LOHP2), and variable frequency local oscillator 3 (LOHP3) are used for the first-stage variable local oscillator of the RF frequency conversion channel. Fixed local oscillator 1 (LOFP1), fixed local oscillator 2 (LOFP2), and fixed local oscillator 3 (LOFP3) are used for the fixed local oscillator of the subsequent frequency conversion channel.

[0084] See also Figure 7 , the auxiliary control unit 6 includes a main control module 6-1, an interface module 6-2 and a base plate 6-3. The main control module 6-1 integrates a controller, a memory and various bus drivers. The CPU completes the control of each module inside the instrument and data acquisition through various buses. The interface module 6-2 mainly completes human-computer interaction, data and interface interaction. The base plate 6-3 realizes the interaction of data, control and power supply among the main control board, the interface module, the signal receiving unit modules, the signal acquisition processing unit modules, the data analysis processing unit modules, the synchronization reference processing unit modules, the frequency synthesis unit modules and the power supply unit.

[0085] See also Figure 8 The power supply unit 7 mainly realizes AC-DC conversion and provides multiple DC power supply functions for each functional module. The power supply unit is mainly composed of an input filter 7-1, a PFC circuit 7-2, a DC / DC module 7-3, a current balancing circuit 7-4 and an output filter circuit 7-5.

[0086] See also Fig. 9 , take an 8-channel receiving unit as the basic unit for testing, and use any unit as the same-layer reference output. The 7-way external synchronization reference output generated by its synchronization reference processing unit is connected to the external synchronization reference input of 7 external 8-channel receiving units, so that a 64-channel synchronization receiver can be generated. Further, through the star connection method, the receiving channels can be infinitely expanded, and finally an 8*n channel receiving system can be formed.

[0087] The present invention is based on an 8-channel receiving stand-alone machine to form 8*n multi-channel receiving hardware, the front end adopts superheterodyne frequency conversion, and the back end processing uses software radio technology to realize the conversion of signals to IQ data.

[0088] The present invention also relates to an amplitude phase consistency test method for obtaining consistency parameters of multi-channel amplitude phase, that is, assessing the amplitude difference and phase difference between signals received by multiple channels at a specific moment. According to test needs, it is divided into frequency domain amplitude phase consistency test and time domain amplitude phase consistency test.

[0089] The frequency domain amplitude and phase consistency between multiple channels is divided into amplitude consistency and phase consistency. The calculation of amplitude consistency and phase consistency is based on the IQ data (that is, complex value) of the obtained signal. The specific steps of the consistency test method are as follows:

[0090] Step 1: Set up the receiver. Setting up the receiver includes the following sub-steps:

[0091] Step S11: Initialize the receiver, start the test task, and call the channel calibration compensation data.

[0092] Step S12: Set the receiver to the frequency domain receiving mode, and set the relevant parameters of the multi-dimensional multi-channel signal monitoring platform according to the frequency band, bandwidth, peak power and number of channels of the tested signal. Among them, the frequency band and bandwidth are set to the center frequency and bandwidth of the receiver respectively, and the bandwidth also determines the measurement bandwidth of the receiver. The peak power is set to the reference level of the receiver, and the number of channels is set to the receiving channel of the receiver.

[0093] Step S13: Start the receiver test task, configure any channel as a reference channel, select a cursor value in any receiving spectrum of the corresponding receiver, and then the frequency values ​​of all receiving channels at this cursor point can be displayed.

[0094] Step 2: Calculate the amplitude difference and phase difference.

[0095] The method for calculating the amplitude difference and the phase difference includes the following sub-steps:

[0096] Step S21: Based on the complex value obtained after the signal is digitally quantized, the amplitude difference of each channel (i=1:7) relative to the reference channel (i=0) can be calculated according to the following formula:

[0097] ;

[0098] Among them, A i is the amplitude difference, in dB;

[0099] i is the channel number, specified by the receiver configuration;

[0100] I i It is the in-phase component of the complex value after the signal is quantized;

[0101] Q i It is the orthogonal component of the complex value after the signal is quantized.

[0102] Step S22: Based on the complex value obtained after the signal is digitally quantized, the phase difference of each channel relative to the reference channel (i=0) can be calculated according to the following formula:

[0103] ;

[0104] Among them, φ i is the phase difference, in degrees (º);

[0105] i is the channel number, specified by the receiver configuration;

[0106] I i It is the in-phase component of the complex value after the signal is quantized;

[0107] Q i It is the orthogonal component of the complex value after the signal is quantized.

[0108] Step S23: By moving the cursor arbitrarily, the frequency of any frequency point within the bandwidth can be obtained. By repeating the calculation method above, the amplitude difference and phase difference of all frequency points can be obtained.

[0109] Step S24: Count the maximum amplitude difference A of all frequency points max , minimum value A min , the maximum phase difference φ max , minimum value φ min The amplitude consistency A and phase consistency φ of the received signals of the corresponding number of channels are calculated according to the following two formulas respectively.

[0110] ;

[0111] .

[0112] The time-domain amplitude phase consistency between multiple channels is also divided into amplitude consistency and phase consistency. The calculation of amplitude consistency and phase consistency is based on the IQ data (that is, complex value) of the obtained signal. The specific steps of the time-domain amplitude phase consistency test method between multiple channels are as follows:

[0113] a. First, set the receiver to the time domain receiving mode. According to the frequency band, bandwidth, peak power and number of channels of the tested signal, set the relevant parameters of the multi-dimensional multi-channel signal monitoring platform. The frequency band and bandwidth are set to the receiver center frequency and measurement bandwidth respectively, the peak power is set to the receiver reference level, and the number of channels is set to the receiver receiving channel.

[0114] b. Start the receiver test task, configure any channel as the reference channel, and enable the cursor value. At this time, the time values ​​of all receiving channels at this cursor point can be displayed accordingly.

[0115] c. Calculate the amplitude difference and phase difference. The calculation method of the amplitude difference and phase difference is the same as the calculation method of the amplitude difference and phase difference in the above frequency domain amplitude and phase consistency test method, and will not be repeated here.

[0116] The above description includes examples of one or more embodiments. Of course, it is impossible to describe all possible combinations of components or methods for the purpose of describing the above embodiments, but it should be recognized by those skilled in the art that the various embodiments may be further combined and arranged. Therefore, the embodiments described herein are intended to cover all such changes, modifications and variations that fall within the scope of protection of the appended claims. In addition, with respect to the term "comprising" used in the specification or claims, the word is covered in a manner similar to the term "including", just as "including," is explained as a transitional word in the claims. In addition, any term "or" used in the specification of the claims is intended to mean "non-exclusive or".

Claims

1. A multi-dimensional multi-channel broadband signal monitoring platform, characterized in that: It is composed of multiple 8-channel receiving units, with 8 units as a group, forming n groups. Each group uses a single 8-channel receiving unit as the basic functional unit. The built-in parallel synchronization reference correction processor of each functional unit generates a synchronization reference signal, and multi-channel cascade correction processing is adopted to receive n*8 parallel signals. The 8-channel receiving unit includes a signal receiving unit, a signal acquisition processing unit, a data analysis processing unit, a synchronization reference processing unit, a frequency synthesis unit, an auxiliary control unit and a power supply unit; The synchronization reference processing unit includes a reference generator, a synchronization reference rule corrector, an external synchronization reference distributor and an internal synchronization reference distributor; The reference generator generates a whole-machine synchronous reference signal, which is the reference for consistency testing of each group of multiple channels; After the synchronization reference rule corrector corrects the synchronization reference signal, it is distributed into two paths after frequency domain consistency and time domain consistency correction, one path is used by the external synchronization reference distributor, and the other path is used by the internal synchronization reference distributor; The external synchronization reference distributor receives the synchronization reference signal after the rule correction and distributes it into 8 channels, which can synchronize 8 external 8-channel receiving units; The internal synchronization reference distributor generates synchronization signals for internal 8-channel parallel sampling, and outputs 16 internal synchronization signals, which are 8 broadband synchronization signals and 8 narrowband synchronization signals.

2. A multi-dimensional multi-channel broadband signal monitoring platform according to claim 1, characterized in that: The signal receiving unit is composed of 8 sets of radio frequency conversion conditioning modules, and the signal processing unit is composed of 8 sets of acquisition modules. The signal receiving unit and the signal processing unit receive electromagnetic signals and convert them into digital signals.

3. A multi-dimensional multi-channel broadband signal monitoring platform according to claim 2, characterized in that: The signal receiving unit is a receiver front end, including a selection switch, a gain control, a preselector, a multi-stage mixer, a switch combining amplifier, a filter and an intermediate frequency conditioning; The selection switch is used to realize the switching between the radio frequency input signal and the calibration signal; The gain control includes two circuits, a variable attenuator and a switching amplifier, to achieve control of the overall gain of the channel signal; The preselector suppresses non-in-band signals according to the frequency characteristic parameters of the signal to be tested, thereby reducing the noise and non-correlated signals entering the receiving channel; The multi-stage mixing filter is used to down-convert or up-convert the high-frequency signal or the low-frequency signal so that the signal frequency band is moved to the frequency band directly quantized by the analog-to-digital converter; The switch combining amplifier is used to combine the intermediate frequencies generated by the combination of multiple mixers and filters to achieve unified back-end processing; The filter performs broadband filtering and narrowband filtering respectively according to the needs of back-end signal acquisition; The intermediate frequency conditioning is divided into broadband level conditioning and narrowband conditioning. The broadband level conditioning adjusts the intermediate frequency signal level to the optimal acquisition area of ​​the broadband analog-to-digital converter; the narrowband conditioning performs an additional down-conversion on the intermediate frequency signal compared to broadband acquisition, reducing it to the acquisition range of the narrowband analog-to-digital converter.

4. A multi-dimensional multi-channel broadband signal monitoring platform according to claim 3, characterized in that: The signal acquisition and processing unit is the digital-to-analog conversion part of the receiver, which is divided into two paths: broadband and narrowband; the signal acquisition and processing unit includes an analog-to-digital converter, digital down-conversion and data interaction processing; The analog-to-digital converter includes a broadband analog-to-digital converter and a narrowband analog-to-digital converter, which respectively receive the broadband intermediate frequency signal and the narrowband intermediate frequency signal from the signal receiving unit, and perform broadband analog-to-digital conversion and narrowband analog-to-digital conversion to generate an intermediate frequency digital signal; The digital down-conversion includes broadband digital down-conversion and narrowband digital down-conversion, multiplying the intermediate frequency digital signal with a complex exponential signal with the same intermediate frequency, and down-converting the bandpass signal to baseband; The data interaction processing of the signal acquisition processing unit further integrates the broadband baseband data and the narrowband baseband data after digital down-conversion and extraction filtering, and performs transmission logic conversion to form unified baseband data.

5. The multi-dimensional multi-channel broadband signal monitoring platform according to claim 4, characterized in that: The data analysis and processing unit receives the extracted and filtered baseband data, classifies it into two parts, broadband data and narrowband data, through the data bus, and further performs frequency domain data processing and time domain data processing. The data analysis and processing unit includes frequency domain data processing, time domain data processing and consistency analysis; The frequency domain data processing includes a narrowband frequency domain data processor and a wideband frequency domain data processor, which receive the data from the signal acquisition processing unit after down-conversion and extraction and filtering, and perform frequency domain processing of broadband signals and frequency domain processing of narrowband signals respectively; The time domain data processing includes narrowband time domain data processing and broadband time domain data processing, receiving the data from the signal acquisition processing unit after down-conversion and extraction and filtering, and performing broadband signal time domain processing and narrowband signal time domain processing respectively; The consistency analysis includes frequency domain consistency analysis and time domain consistency analysis; the frequency domain consistency analysis receives narrowband frequency domain data and broadband frequency domain data, performs consistency analysis on the data within the set bandwidth of multiple channels with any channel as a reference channel, obtains the corresponding array relationship of frequency-channel-jitter and reports the test results; The time domain consistency analysis receives narrowband time domain data and broadband time domain data, performs consistency analysis on data within a time period determined by multiple channels using any channel as a reference channel, obtains a corresponding array relationship of time-channel-jitter and reports the test result.

6. A multi-dimensional multi-channel broadband signal monitoring platform according to claim 5, characterized in that: The frequency synthesis unit generates a unified clock reference through an internal clock reference based on a reference signal, and distributes it to eight types of signal generators to generate a calibration signal, three frequency-converting local oscillator signals and three fixed local oscillator signals.

7. The multi-dimensional multi-channel broadband signal monitoring platform according to claim 1, characterized in that: The auxiliary control unit comprises a main control module, an interface module and a base plate; The power supply unit realizes AC-DC conversion and provides a multi-channel DC power supply function. The power supply unit includes an input filter, a PFC circuit, a DC / DC module, a current balancing circuit and an output filter circuit.

8. A method for testing amplitude and phase consistency, characterized in that: It includes frequency domain amplitude phase consistency test and time domain amplitude phase consistency test. The time domain amplitude phase consistency test includes the following three steps: a. First, set the receiver to the time domain receiving mode. According to the frequency band, bandwidth, peak power and number of channels of the tested signal, set the relevant parameters of the multi-dimensional multi-channel signal monitoring platform. The frequency band and bandwidth are set to the center frequency and measurement bandwidth of the receiver, the peak power is set to the reference level of the receiver, and the number of channels is set to the receiving channel of the receiver. b. Start the receiver test task, configure any channel as the reference channel, and enable the cursor value. At this time, the time value of all receiving channels at this cursor point can be displayed; c. Calculate the amplitude difference and phase difference.

9. The method according to claim 8, characterized in that The frequency domain amplitude phase consistency test includes the following two steps: Step 1: Set up the receiver, including the following sub-steps: Step S11: Initialize the receiver, start the test task, and call the channel calibration compensation data; Step S12: Set the receiver to the frequency domain receiving mode, and set the relevant parameters of the multi-dimensional multi-channel signal monitoring platform according to the frequency band, bandwidth, peak power and number of channels of the tested signal. Among them, the frequency band and bandwidth are set to the center frequency and bandwidth of the receiver respectively, and the bandwidth also determines the measurement bandwidth of the receiver. The peak power is set to the reference level of the receiver, and the number of channels is set to the receiving channel of the receiver. Step S13: Start the receiver test task, configure any channel as a reference channel, select a cursor value at any receiving spectrum of the corresponding receiver, and then the frequency values ​​of all receiving channels at this cursor point can be displayed; Step 2: Calculate the amplitude difference and phase difference.

10. The method according to any one of claims 8 and 9, characterized in that In the frequency domain amplitude phase consistency test and the time domain amplitude phase consistency test, the specific method for calculating the amplitude difference and the phase difference is: Step S21: Based on the complex value obtained after the signal is digitally quantized, the amplitude difference of each channel (i=1:7) relative to the reference channel (i=0) can be calculated according to the following formula: ； Among them, A i is the amplitude difference, in dB; i is the channel number, specified by the receiver configuration; I i It is the in-phase component of the complex value after the signal is quantized; Q i is the orthogonal component of the complex value after the signal is quantized; Step S22: Based on the complex value obtained after the signal is digitally quantized, the phase difference of each channel relative to the reference channel (i=0) can be calculated according to the following formula: ； Among them, φ i is the phase difference, in degrees (º); i is the channel number, specified by the receiver configuration; I i It is the in-phase component of the complex value after the signal is quantized; Q i is the orthogonal component of the complex value after the signal is quantized; Step S23: Move the cursor arbitrarily to obtain the frequency of any frequency point within the bandwidth, and repeat the calculation method above to obtain the amplitude difference and phase difference of all frequency points; Step S24: Count the maximum amplitude difference A of all frequency points max , minimum value A min , the maximum phase difference φ max , minimum value φ min Calculate according to the following two formulas, namely, the amplitude consistency A and phase consistency φ of the received signal corresponding to the number of channels; ； 。

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