RU94096U1 - RADIO RECEIVER FOR AUTOMATED SIGNAL RADIOMONITORING - Google Patents

Abstract

 A radio receiving device for automated radio monitoring of signals, comprising two tuners, each of which consists of a series-switched switched preselector, a first mixer, a selective amplifier of the first intermediate frequency, a second mixer, a selective amplifier of the second intermediate frequency and an analog-to-digital converter, and also containing a reference frequency synthesizer , the corresponding outputs of which are connected to the second inputs of the first and second mixers of each tuner, and personal an electronic computer, characterized in that a first quadrature component driver, a first digital filtering unit, a first resampler, a spectrum regenerator, an energy analyzer, a panoramic analysis unit, an output data generating unit, a second quadrature component driver, a second digital filtering unit are introduced into it, second resampler, detector, carrier corrector, clock corrector, equalizer, software unit and a fully accessible switch, the signal inputs of which correspond to each tuner is connected to the outputs of the analog-to-digital converters, the first output through the first quadrature component driver, the first digital filtering unit, the first resampler, spectrum regenerator and energy analyzer connected to the first input of the output data generating unit, and the second output through the second quadrature component driver, the second digital filtering unit, the second resampler and detector are connected to the third input of the output data generating unit, the second output of the detector through the equalizer

Description

The utility model relates to radio engineering and can be used for radio monitoring of signals, in particular for automated radio monitoring of radio signals of various sources of radio emissions (IRI) in a wide frequency range.

Radio monitoring provides for:

- panoramic review and analysis in the working frequency range;

- determination of the load range in the coordinates of the amplitude-frequency-time-bearing;

- Comparison with the “reference panorama” and the search for new frequencies;

- direction finding of each IRI;

- registration of radio signals to the hard disk, measurement of their parameters, technical analysis.

Radio monitoring is provided by a complex of hardware: antenna and radio receivers, signal demodulators with various types of modulation, spectrum analyzers, recording and computer analysis tools. Minimizing the composition of monitoring tools allows you to reduce the likelihood of errors in solving the tasks, increase the accuracy of measurements, guarantee the completeness of the analysis and reduce session time. The basis of the composition is a radio receiver.

Known radio receiver for radio monitoring of signals (receiver for radio reconnaissance), described in the application of Germany No. OS 3044701 [1].

The device comprises a tuner, which consists of a series-connected selective high-frequency amplifier, a first mixer, a selective amplifier of the first intermediate frequency (IF), a second mixer and a selective amplifier of a second frequency converter. The reference signals for the frequency converter are generated by the first and second local oscillators. To control the signals, a spectrum analyzer is used; there is a channel for tonal signal listening. The device provides control of signals in a given section of the frequency range.

The disadvantages of the known device is the limited amount of data obtained by IRI and the low reliability of the monitoring results.

This is because the structure of the device provides for the control of signals of only one range or part of the frequency range. Tone control of signals does not provide information on the type of analog or digital modulation; demodulation by the device during monitoring is not carried out. The spectrum analyzer and tuner have autonomous control, which significantly increases the time to determine the parameters of the IRI. The stability of the receiver analog local oscillators is low.

Known radio receiver for radio monitoring of signals (receiver control point) used in the station according to patent RU 2313911 [2]. The device comprises a tuner, which consists of a series-connected selective high-frequency amplifier, a mixer, and an IF amplifier. There is a synchronous detector and signal extraction nodes for combined amplitude modulation and phase shift keying (AM-PSK), a recording and analysis unit. Descramblers implement cryptographic methods for protecting confidential analog and digital messages of communication systems of their own radio monitoring service.

The disadvantages of the device are the limited amount of data obtained by IRI and the low reliability of the monitoring results.

This is due to the fact that the structure of the device is focused on monitoring signals of only one range or part of a frequency range. A single conversion of the intermediate frequency does not allow for high selectivity for the input specular frequency. The device does not control the types of manipulation, which is very important when monitoring digital signals. The analog local oscillator does not allow to realize high stability. As a result, the accuracy of the measurements is reduced. Autonomous control of the tuner and the recording and analysis unit increases the time for determining the IRI parameters and reduces their accuracy.

The closest in technical essence to the claimed object is a radio receiving device for automated radio monitoring of signals described in the source [3].

The device contains two tuners, each of which consists of a series-connected switched preselector, a first mixer, a selective amplifier of the first inverter, a second mixer, a selective amplifier of the second inverter and an analog-to-digital converter (ADC), and also contains a reference frequency synthesizer, the corresponding outputs of which are connected to the second inputs of the first and second mixers of each tuner, and a personal electronic computer (PC). A PC is used to record radio signals in vector form and subsequent in deferred mode automated technical analysis and determination of modulation and transmission parameters. Tuners and PCs have independent autonomous control. The introduction of a switched preselector into each tuner allowed to significantly expand the range of controlled frequencies and to monitor the most important parts of the range. The reference frequency synthesizer significantly increased the accuracy of the measurements and made it possible to analyze in the deferred mode the extremely narrow IRI signals in the spectrum width. The use of two tuners in the device makes it possible to determine not only the bearing, but also the coordinates of the IRI.

However, the disadvantages of the known device are the limited amount of data obtained by IRI and the lack of reliability of the monitoring results.

This is explained by the fact that to determine and measure a number of IRI parameters, it is necessary to use structurally autonomous and control-independent hardware together with a radio receiver: a spectrum analyzer, a device for determining complex types of digital manipulation, for example, according to the patent [4], digital signal demodulators, oscillographic indicators.

Independent control of all these devices leads to difficulties in ensuring synchronization, reduces the accuracy of measurements. Errors appear, especially in the classification of signals that reduce the reliability of the data obtained, the duration of a single cycle of radio monitoring increases.

The purpose of creating a useful model is to increase the amount of data obtained on the IRI and increase the reliability of monitoring results.

This goal is achieved due to the fact that in a known radio receiver for automated radio monitoring of signals, containing two tuners, each of which consists of a series-connected switched preselector, a first mixer, a selective amplifier of the first inverter, a second mixer, a selective amplifier of the second inverter and ADC, and also containing a reference frequency synthesizer, the corresponding outputs of which are connected to the second inputs of the first and second mixers of each tuner, and a personal computer, the first form quadrature component switcher, first digital filtering block, first resampler, spectrum regenerator, energy analyzer, panoramic analysis unit, output data generating unit, second quadrature component shaper, second digital filtering block, second resampler, detector, carrier corrector, clock corrector, equalizer , a software unit and a fully accessible switch, the signal inputs of which are connected to the outputs of the ADCs of each tuner, the first output through the first quadrature driver a component, a first digital filtering unit, a first resampler, a spectrum regenerator and an energy analyzer connected to the first input of the output data forming unit, and a second output through the second quadrature component former, a second digital filtering unit, a second resampler and detector connected to the third input of the output data generating unit moreover, the second output of the detector through the equalizer is connected to the second input of the second driver of the quadrature components, the third output of the detector through the carrier corrector is connected with the control input of the second digital filtering unit, the fourth output of the detector through the clock corrector is connected to the control input of the second resampler, the software unit is connected to the second input of the PC, and the second output of the spectrum regenerator through the panoramic analysis unit is connected to the second input of the output data generating unit, output which through a PC is connected to the control inputs of a fully accessible switch and a reference frequency synthesizer, while the inputs of the tuner tuners preselectors are inputs s radio receiving apparatus for automated radio monitoring signals.

New significant features are components of a single radio receiver, synchronized through a PC, which performs not only the functions of recording and technical analysis of signals in deferred mode, but also the functions of a single control body, as well as the technical analysis and demodulation of multi-position digital signals in real time. This makes it possible to eliminate information loss and increase the reliability of monitoring results, as well as drastically reduce the time it takes to carry out a full monitoring cycle of specified frequency ranges.

The combination of distinctive features and properties of the proposed radio receiver for automated radio monitoring of signals from the literature is not known, therefore, it meets the criterion of novelty.

Figure 1 shows the functional diagram of a radio receiving device for automated radio monitoring of signals.

The radio receiving device for the automated radio monitoring of signals contains two tuners 1, 2, each of which consists of a series-switched switching preselector 3, a first mixer 4, a selective amplifier 5 of the first inverter, a second mixer 6, a selective amplifier 7 of the second inverter and ADC 8, and also contain a reference frequency synthesizer 9, the corresponding outputs of which are connected to the second inputs of the first and second mixers 4, 6 of each tuner 1, 2, and PC 10. The first driver 11 square is introduced into the radio receiver component, the first digital filtering unit 12, the first resampler 13, the spectrum regenerator 14, the energy analyzer 15, the panoramic analysis unit 16, the output data generating unit 17, the second quadrature component driver 18, the second digital filtering unit 19, the second resampler 20, detector 21 , carrier equalizer 22, clock equalizer 23, equalizer 24, software block 25 and fully accessible switch 26, the signal inputs of which are respectively connected to the outputs of the ADC 8 of each tuner 1, 2, the first output through the first a quadrature component ripper 11, a first digital filtering block 12, a first resampler 13, a spectrum regenerator 14 and an energy analyzer 15 are connected to the first input of the output data generating block 17, and a second output through the second quadrature component shaper 18, the second digital filtering block 19, the second resampler 20 and the detector 21 is connected to the third input of the output data generating unit 17. The second output of the detector 21 through the equalizer 24 is connected to the second input of the second driver 18 of the quadrature components. The third output of the detector 21 through the corrector 22 of the carrier is connected to the control input of the second digital filtering unit 19, the fourth output of the detector 21 through the corrector 23 of the clock frequency is connected to the control input of the second resampler 20. The block 25 of the software is connected to the second input of the PC 10. The second output of the regenerator 14 spectrum through the node 16 panoramic analysis is connected to the second input of the block 17 of the formation of the output data, the output of which is through a PC 10 connected to the control inputs of the fully accessible switch 26 and synthesizer 9 r frequencies. The inputs of the switched preselectors 3 of the tuners 1, 2 are the inputs of the radio receiving device for the automated radio monitoring of signals.

The radio receiving device (figure 1) operates as follows.

The device provides the following modes of operation:

- a panoramic view mode of the specified sections of the frequency ranges, which ensures the determination of the load of these sections in the amplitude-frequency-time-bearing system and comparison with the “reference panorama” of the channel of the blocks 11 ÷ 17, 10, 25 obtained from the previous control;

- a search mode for new signals, which ensures the determination of the IRI parameters in the amplitude-frequency-time-bearing system, the determination of the type of modulation, demodulation and registration of signals on a hard magnetic disk for further analysis in deferred mode, provided by a channel of blocks 18 ÷ 24, 10, 25, 17.

Other combined modes of operation of the device are possible, including semantic control of individual signals.

The tuners of the radio receiver can be oriented both to one IRI, for example, at location, and to different IRI.

Controlled signals are fed to the inputs of tuners 1, 2 and in each of them are pre-filtered in a switched preselector 3 and fed to the first mixer 4, the reference signal to the second input of which is supplied from the first output of the reference frequency synthesizer 9. Next, the controlled signals pass the selective amplifier 5 of the first inverter, are converted to the second inverter in the second mixer 6, the reference signal to which is supplied from the second output of the synthesizer 9 of the reference frequencies, the selective amplifier 7 of the second inverter passes and fed to the ADC 8. All further signal processing digital form. Tuners 1, 2 and synthesizer 9 reference frequencies structurally may be similar to the prototype.

From the outputs of the ADC 8 of each tuner 1, 2, the signals are fed to the first and second inputs of the fully accessible switch 26, operating on the principle of "each with each", that is, any of the inputs of the switch 26 can be switched to any output number.

From the first output of the switch 26, the signal is supplied to the first driver 11 of the quadrature components of the channel of spectral measurements, providing reduction to a complex form. The first shaper 11 of the quadrature components can be performed, for example, on the basis of the Hilbert transducer [5, p. 320, 321], built on a recursive filter of order 2N with antisymmetric coefficients B _m . · In general, a complex signal

where jx [n] is the Hilbert-conjugated digital signal from the signal x (n).

The signals x (n) and jx [n] are a pair of quadrature components of the digital signal, since multiplication by the imaginary unit j is equivalent to the phase shift of all spectral components of the signal x (n) by π / 2.

An ideal Hilbert transducer should have a complex gain

The system function of a non-recursive filter of order 2N is described by the expression

For the expression K (j ) is replaced by z ^-1 = resulting in will

Given the Euler formula:

To provide it is necessary to take B ₀ = 0, therefore

Since an ideal Hilbert converter requires an infinitely large number of delay elements, it is necessary to limit this number and to implement, for example, take 2N = 6. Then, for _B2 = 0

Close to flat frequency response in the vicinity it is provided when the coefficients B ₁ = 0.6, B ₃ = 0.1.

Quadrature components from the output of the first driver 11 are supplied to the first block 12 of digital filtering, which can be performed, for example, similarly [6, p.1061]. The number of links N ₃ filtration is determined by the degree of decimation The filtered signal components from the output of block 12 are supplied to the first resampler 13.

Resampler 13 provides resampling of the digitized signals necessary for synchronous operation in real time of the analysis and demodulation units of the radio receiver, as well as eliminating or minimizing errors during registration for subsequent analysis in deferred mode. Resampler 13 can be performed in accordance with the recommendations of [7, p. 381-409]. The combination of decimation and interpolation in the resampler allows you to implement the conversion of the sampling frequency with any rational coefficient M / D by sequentially performing interpolation M times and decimation by D times. Since the M / D ratio can be obtained with any desired accuracy with the correct choice of integer M and D, this makes it possible to practically realize any value of the conversion coefficient.

The output signals of the resampler 13 are fed to a spectrum regenerator 14 using a discrete Fourier transform (DFT) [7, pp. 63-132].

The complex Fourier coefficients C _{k of the} periodic function f (t) with period 2π can be expressed as the scalar product f (t) and e ^jkt :

In this case, the Fourier coefficients are defined as the coefficients of the N-dimensional vector represented by a series of N signal values approximating the function f (t). If the corresponding function e ^{jkt is an} N-dimensional vector whose components are complex numbers, denoted as e _k , then the Fourier coefficients for the vector f can be defined as the non-polar product:

i.e. DFT:

The inverse of the DFT is defined as

For the DFT, the Parseval theorem holds:

that is, the energy in the frequency and time domains are the same.

The spectral components of the complex signals from the second output of the spectrum resampler 14 are fed to the panoramic analysis node 16, which provides spectrum accumulation and energy analysis by summing the frequency samples over time. Averaging allows you to adapt the spectrum display for different update and analysis rates. Compiling a spectrum of large frequency intervals is carried out by sequentially repeating the following operations:

- rebuilding the tuner to the next area of interest;

- adjustment of the carrier frequency;

- tuning in clock frequency, providing the desired resolution of the spectrum.

The results of the panoramic analysis are fed to the second input of the output data generating unit 17, which is an interface device for coordination with a PC 10.

From the first output of the spectrum regenerator 14, the signal is fed to an energy analyzer 15, which allows one to evaluate the harmonic components of the spectrum and thereby determine the main types of digital modulation. The evaluation results are received at the first input of the output data generating unit 17.

From the second output of the fully accessible switch 26, the signal is supplied to the first input of the second driver 18 of the quadrature components of the demodulation channel. The second driver 18 can be performed, for example, on the basis of a digital frequency converter [5, p. 322, 323, Fig. 7.14]. The reduction to a complex form in this case consists in multiplying the input samples by the samples of the reference generator, while the sine component is used for the real part (quadrature I), and the cosine component for the imaginary part (Q). The number of samples per one generator period determines the shift of the signal spectrum in frequency, changing this parameter by the influence of the control signal at the second input of the shaper 18.

The subsequent processing of the complex signal in the demodulation channel of the radio receiver is carried out similarly to the channel of spectral measurements: the signal is filtered by the second digital filtering unit 19, the second resampler 20 passes and fed to the detector 21. Unit 19 and resampler 20 are structurally similar to the corresponding blocks of the panoramic measurement channel 12, 13, but have additional inputs for supplying control signals, ensuring the adaptation of the parameters of the blocks to the parameters of the monitored signals. From the outputs of the resampler 20, the signals are fed to the detector 21, which allocates pseudo-random digital streams, depending on the type of modulation and information transfer rate. The signal necessary for the demodulation adjustment of the carrier frequency is generated by the carrier corrector 22 connected to the third output of the detector 21 and fed to the control input of the digital filtering unit 19. The signal necessary for the demodulation of the clock frequency adjustment is generated by the clock corrector connected to the fourth output of the detector 21 and fed to the control input of the second resampler 20.

Under conditions of a priori unknown distortions in the radio channel and the presence of Gaussian noise, intersymbol distortions (ISI) appear, causing radio monitoring errors [8, p. 502].

The monitored signal (equivalent low-frequency) is expressed as

where I _n - information pulse sequence;

h (t) is the response of the equivalent low-frequency channel to the input signal pulse g (t), and z (t) represents white Gaussian noise.

The sequence at the output of the detector 21

where ν _k means a sequence of samples of additive noise at the output, i.e.

The output samples are distorted by the ISI. But the MCI affect a limited number of characters, therefore, the MCI at the output of the detector 21 can be considered as a function with a finite number of states. This allows equalization by using an equalizer 24, the input of which is connected to the second output of the detector 21, and the output is connected to the second input of the second driver 18 of the quadrature components.

As an equalizer 24, for example, a device based on an equalizer with feedback can be used according to the solution of [8, p.532], which consists of two filters: a direct filter and a feedback filter.

When implementing the detector 21, for example, recommendations can be taken into account [5, Ch. 7.5, p. 341].

From the first output of the detector 21, the signal is supplied to the third input of the output data generating unit 17.

Further operations to demodulate each signal (decoding, descrambling, demultiplexing and extracting the information stream) are performed by software using a personal computer 10. The total signal stream of the output data generating unit 17 is fed to the first input of the personal computer 10. The personal computer 10 generally provides radio receiver control functions, signal demodulation, control and recording of received data. Work programs are set by block 25 of the software.

Blocks 26, 11-13, 18-20 can be performed, for example, on the basis of the GC4016 chip, and blocks 14-17, 21-24 on the basis of the TMS 320C6416 processor.

Structurally, the radio receiver can be implemented in the form of cards, geographically located in the PC case, or in the form of an autonomous tuner case with blocks of the panoramic channel and demodulation, as well as an external PC. Means of implementing the utility model make it possible to ensure its industrial applicability.

Used sources.

1 Radio intelligence receiver. Application FRG No. OS 3044701, MKI H03J 7/18, Publication 08.07.1982, No. 27.

2 Radio intelligence station. Patent RU 2313911, IPC Н04К 1/10, published December 27, 2007

3 Rembovsky A.M., Ashikhmin A.V., Sergienko A.R. Wearable Automated Radio Monitoring. Special Technique No. 4, 2004 (Special Issue, pp. 39-47).

4 Utility Model Patent No. 77051. IPC G01R 23/46. Registered 10.10.2008. A device for recognizing types of manipulation of digital signals.

5 Fomin N.N. and other radio receivers. - M .: Hot line - Telecom. 2007.

6 Sklyar Bernard. Digital communication. Theoretical foundations and practical application. Publishing House "Williams", 2003.

7 Richard Lyons. Digital signal processing. -M .: Binom-Press LLC, 2006.

8 Prokis J. Digital Communications. - M .: Radio and communications, 2000.

Claims (1)

A radio receiving device for automated radio monitoring of signals, comprising two tuners, each of which consists of a series-switched switched preselector, a first mixer, a selective amplifier of the first intermediate frequency, a second mixer, a selective amplifier of the second intermediate frequency and an analog-to-digital converter, and also containing a reference frequency synthesizer , the corresponding outputs of which are connected to the second inputs of the first and second mixers of each tuner, and personal an electronic computer, characterized in that a first quadrature component driver, a first digital filtering unit, a first resampler, a spectrum regenerator, an energy analyzer, a panoramic analysis unit, an output data generating unit, a second quadrature component driver, a second digital filtering unit are introduced into it, second resampler, detector, carrier corrector, clock corrector, equalizer, software unit and a fully accessible switch, the signal inputs of which correspond to each tuner is connected to the outputs of the analog-to-digital converters, the first output through the first quadrature component driver, the first digital filtering unit, the first resampler, spectrum regenerator and energy analyzer connected to the first input of the output data generating unit, and the second output through the second quadrature component driver, the second digital filtering unit, the second resampler and detector are connected to the third input of the output data generating unit, the second output of the detector through the equalizer connected to the second input of the second shaper of the quadrature components, the third output of the detector through the carrier corrector is connected to the control input of the second block of digital information, the fourth output of the detector through the clock corrector is connected to the control input of the second resampler, the software unit is connected to the second input of the personal computer and the second output of the spectrum regenerator through the panoramic analysis node is connected to the second input of the output data generating unit, the output is cerned through personalized electronic computer is connected to control inputs of the switch-blocking and synthesizer reference frequency, the inputs are switched Preselectors Tuner inputs receiving device for automated radio monitoring signals.