SU1166008A1 - Device for spectral analysing of signals - Google Patents

Abstract

A DEVICE FOR SPECTRAL ANALYSIS OF SIGNALS containing an analog-to-digital converter, digital shift registers, a digital-to-analog converter, the corresponding inputs of which are connected to the outputs of digital shift registers, a dispersive spectrum analyzer whose input is connected to the output of the digital-analog converter, and a synchronizer whose first output is a spectrum analyzer whose input is connected to the output of the digital-analogue converter, and a synchronizer whose first output of which is connected to a digital-to-analog converter, and a synchronizer whose first output is a spectrum analyzer whose input is connected to the output of a digital-analogue converter, and a synchronizer that has a digital output converter that is connected to the digital-analogue converter; control of the analog-to-digital converter input, the second t with the clock singing inputs of the digital shift registers, and the third with synchronization Iruyuvom input dispersion spectrum analyzer, different. By the fact that, in order to increase the dynamic range, the analog switchboard, logical switches and elements AND are introduced according to the number of digital shift registers, as well as a code converter, the outputs of which are connected to the digital output of the device, the inputs are connected to the outputs of the corresponding AND elements, and the clocking the input is connected to the fourth output of the synchronizer, and the first input of the analog switch is connected to the input of the ycTpcrflstva, its control input is connected to the control inputs of the logic switches, the second in the moves of the elements And and p 5 output of the synchronizer, the second input of the analog S. the switch is connected to the output of the dispersive spectrum analyzer, and the output is connected to the input of the analog-digital converter, the first inputs of the logic switches are connected to the corresponding outputs of the analog-digital converter, their second inputs are from the output (the corresponding digital shift register, and Od outputs - to the input of the same digital O shift register, with the first inputs of the elements And. are connected to the left input corresponding to logical switches.

Description

1 The invention relates to the field of radio measurements and is intended for spectral analysis of signals, and since it displays information in digital form, it can be used to work in conjunction with a digital computer. The closest in technical essence to the invention is a device for spectral analysis of signals, which is a combination of a digital compressor, a dispersive spectrum analyzer and an output analog-digital converter (A / D converter). The device contains ADCs, digital shift registers, the input of each of which is connected to the corresponding output of the ADC, a synchronizer, a digital-to-analog converter and a dispersion spectrum analyzer, the input of which is connected to the output of a digital-to-analog converter 1 J. A disadvantage of the known device is that its dynamic 1st range is limited output due to the fundamental limitations of the parameters of the output ADC. The purpose of the invention is to increase the dynamic range of the device. The goal is achieved by the fact that in a device containing an ADC, digital shift registers, a digital-analog converter, the corresponding inputs of which are connected to the outputs of digital shift registers, a dispersive spectrum analyzer whose input is connected to the output of the digital-analog converter, and a synchronizer whose first output is connected to control of the ADC input, the second one with the clock inputs of the digital shift registers, and the third one with the synchronization input of the dispersive spectrum analyzer, are entered tax switch, logical switches and elements And by the number of digital shift registers, as well as the code converter, the outputs of which are connected to the digital output of the device, the inputs are connected to the outputs of the corresponding elements AND, and the clock input is connected to the fourth output of the synchronizer, and the first input of the analog switch is connected with the device input, its 82 control input is connected to the control inputs of logical switches, the second inputs of the AND elements and the fifth output of the synchronizer, the second input is the analog The main switch is connected to the output of the dispersive spectrum analyzer, and the output is connected to the ADC input, the first inputs of the logic switches are connected to the corresponding ADC outputs, their second inputs are connected to the output of the corresponding digital shift register, and the outputs are connected to the same digital shift register, while the first inputs of the elements I. are connected with the first inputs of the corresponding logical switches. An increase in the dynamic range (on devices is ensured by the fact that the output signal of the dispersive spectrum analyzer is digitized using a low-speed multi-bit ADC, also used in the information recording mode in digital shift registers. Switching the ADC from the input processing mode to the processing of the output signal is performed using an analog switch. In this case, the use of a low-speed ADC becomes possible due to multiple The analysis shows a block diagram of the proposed device, a device for spectral analysis of signals contains ADC 1, digital shift registers 2-1, ..., 2-N, 1; and analog-to-analog converter 3 The corresponding inputs of which are connected to the outputs of registers 2-1, ..., 2-N "A dispersion analyzer is also included in the device. 4 spectra, the input of which is connected to the output of the digital-to-analog converter 3, and the synchronizer 5, the first output otorrhea connected to the control input of the ADC 1, the second with timing inputs of registers 2-1, ..., 2-N, and the third - the dispersion to the synchronization input 4 of the spectrum analyzer, an analog switch 6, wherein the first input is an input device, the second

3

the input is connected to the output of the dispersion analyzer 4 of the spectrum, and the output is connected to the input of ADC 1, AND logical switches 7-1, ..., 7-N, the first input of each of which is connected to the corresponding output of ADC 1, the second input - with the output of the corresponding digital shift register, and the output - with the input of the same digital shift register. The device also contains elements AND 8-1, ..., 8-N, the first inputs of which are connected to the first inputs of the respective logic switches 7-1 ,, .., 7-N, and the code converter 9, the outputs of which are digits the output of the device, and the inputs are connected to the outputs of the corresponding elements And 8-1, ..., 8-N, and the control inputs of the analog switch 6 are combined with the control inputs of the logic switches 7-1, ..., 7-N and the second the inputs of the elements are 8-1, ..., 8-N and connected to the fifth output of the synchronizer, and the clock input of the converter 9 is connected to the fourth Erased synchronizer output 5.

The device works as follows.

In the initial state, the first input of the analog switch 6 is connected to its output, i.e. the signal under study is fed to the input of the A / D converter 1, where information about its form is converted into a digital code. In the initial state of the control, the inputs of the logical switches 7-1, ..., 7-N and the second inputs of the AND elements 8-1,.,., 8-N do not receive control signals, as a result of which the ADC 1 outputs are connected to the inputs of the respective digital shift registers 2-1, ..., 2-N. Such an initial state is maintained throughout the entire cycle of analog-to-digital conversion and recording of digital information into shift registers 2-1, .. ,, 2-n. The conversion and recording of information is performed with a frequency determined in accordance with the Kotelnikov theorem.

After the information about the input signal is recorded in the device memory (i.e., all the digits of the digital registers 2-1, ..., 2-N are written down in the device memory), a cyclic reading is performed.

formations about the recorded signal from the registers. In this mode of operation of the device, a control signal appears at the fourth output of the synchronizer, as a result of which, through the second input of the analog switch 6, the output of the dispersion analyzer 4 is connected to the input of the A / D converter 1. In addition, to the second inputs. logical switches 7-l, ..., 7-N, the output of each of the registers 2-1, ..., 2-N turns out to be connected to its own code, and the information from the outputs of ADC 1 is transmitted through the open elements AND

8-1, ..., 8-N to the corresponding inputs of the converter code 9.

The clock inputs of the digital shift registers 2-1, ..., 2-N receive pulses that follow at a much higher frequency than when writing information about the input signal. As a result, the output of the digital-to-analog converter 3 appears compressed in time to a copy of the input signal, which in terms of the duration and width of the spectrum is matched with the parameters of the dispersion analyzer 4 of the spectrum. By-

Q since the ADC speed is not enough to process the output signal of the dispersion analyzer 4 in one cycle, the information about the spectrum is transformed into several cycles. If, for example, the speed of the ADC is four times lower than what is required to process the signal from the output of the dispersion analyzer 4, the number of such cycles (n) should be taken as four. Then, in the first cycle, the following samples are encoded from the analyzer output signal 4: 1.5.9, ..., (K-3); in the second

 cycle: 2,6,10, ... (K-2); in the third cycle: 3,7,11,.,., (K-1); in the fourth cycle: 4,8,12, ..., K, where K is the number of samples (samples) of the output signal of the dispersion analyzer of the torus, defined in accordance with the Kotelnikov theorem. Thus, the required conversion time of the information about c1MSh1 of each sample is increased in the example shown by 4 times.

After the end of the fourth cycle, the memory of the 9 krd converter is recorded.

Claims (1)

DEVICE FOR SPECTRAL SIGNAL ANALYSIS, comprising an analog-to-digital converter, digital shift registers, a digital-to-analog converter, the corresponding inputs of which are connected to the outputs of digital shift registers, a dispersive spectrum analyzer, the input of which is connected to the output of the digital-to-analog converter, and a synchronizer, the first output of which is connected with the control input of the analog-to-digital converter, the second with the clock inputs of the digital shift registers, and the third with the clock in a dispersion spectrum analyzer, characterized in that, in order to increase the dynamic range, an analog switch, logical switches and elements по by the number of digital shift registers, as well as a code converter, the outputs of which are connected to the digital output of the device, are inserted into it, the inputs are connected to the outputs corresponding elements And, and the clock input is connected to the fourth output of the synchronizer, and the first input of the analog switch is connected to the input of the device, its control input is connected to the input inputs of the logical switches, the second inputs of the AND elements and the fifth output of the synchronizer, the second input of the analog switch is connected to the output of the dispersive spectrum analyzer, and the output is connected to the input of the analog-to-digital converter, the first inputs of the logical switches are connected to the corresponding outputs of the analog-to-digital converter, their second inputs are with the output of the corresponding digital shift register, and the outputs with the input of the same digital shift register, while the first inputs of the elements And. connected to mi inputs of the corresponding logic commutators.