RU78615U1 - DEVICE FOR DETERMINING THE CARRIER FREQUENCY OF A DISTORTED ELECTRICAL SIGNAL - Google Patents

Abstract

A device for determining the carrier frequency of a distorted electrical signal can be used to restore distorted electrical signals in system engineering, radio engineering, information technology and other areas related to the reception and transmission of information data. The device contains a block for processing results and information connected to a correlation analyzer of the received signal, which is a series-connected Fourier transform, a correlation filter and an inverse Fourier transform. Achieved technical result - expanding the arsenal of tools and simplifying the design. 1 nz P. f-ly, 4 Fig.

Description

The utility model relates to systems for receiving and processing electrical signals and can be used to restore distorted electrical signals in system engineering, radio engineering, information technology and other areas related to the reception and transmission of information data.

A device for determining the carrier frequency of a distorted electrical signal for its reconstruction, containing a signal source from which the signal enters the signal encoding unit, from which the signal enters the transmitter and then to the communication line, a receiving device, the signal from which through the limiter enters the decoder and a digital information output unit. The signal encoding unit is made in the form of an adder modulo two associated with a storage device in which a copy of the signal is located, and the decoder contains a unit for calculating the mutual correlation function of the signal and the copy and a threshold device associated with the unit for calculating the mutual correlation function and the digital information output unit, the unit for calculating the mutual correlation function along the channel of the sign is connected to the unit for issuing digital information and includes an adder modulo two, performing a bitwise signal equalization and copies of RU 2109401, Н04 В 1/62, 1/69, 1998).

There is also known a device for determining the carrier frequency of a distorted electrical signal, which contains more than one receiving channel, each of which consists of an analog adder and a coherent receiver with a digital output, a first digital adder, a second digital adder, and a reference driver to increase the accuracy of the digital frequency correction of the received signals. signal and crystal oscillator (RU 2208237, G01S 13/14, Н04 В 1/62, G01S 7/288, 2003).

These technical solutions are complex in terms of design and operation.

Closest to the claimed is a device for determining the carrier frequency of a distorted electric signal, containing an adjustable reference frequency generator, a correlation analyzer of the received signal, while the first input of the correlation analyzer is connected to the source of the received electric signal, the second input of the correlation analyzer is connected to the reference frequency generator, information output the correlation analyzer is connected to the input of the processing unit of the results and information, and control the first output of the correlation analyzer is connected to the control input of the adjustable reference frequency generator, and the correlation analyzer is configured to determine the correlation ratio of the received and reference signals (DE 10021346, G06F 1/06, G11C 7/10, G11C 7/22 H04B 1/62, 2000 ; US 6983010, H03H 7/30, 2006).

The prototype device is also complex, because it contains a signal generating circuit for comparing the reference frequency. In addition, its decision blocks are made of analog elements, which makes it difficult to use the known device in digital information and analytical systems.

The technical task of the proposed utility model is to expand the arsenal of tools used to simplify the design and the possibility of using the device as part of digital computing.

The solution to this technical problem is that in a device for determining the carrier frequency of a distorted electrical signal containing a received signal correlation analyzer connected to a result and information processing unit, the received signal correlation analyzer includes a series-connected Fourier converter, a correlation filter, and an inverse Fourier converter.

The causal relationship of the changes made with the achieved technical result is that when the calculations are transferred to the frequency domain using the direct and inverse Fourier converters, there is no need for a comparison circuit with reference signals of different frequencies.

In the technical implementation of the proposed device, the main blocks of the correlation analyzer can be performed on the basis of the following microcircuits: Fourier transducer - Spartan-3 microcircuit from Xilinx; correlation filter - Vertex-4 microcircuit from Xilinx; inverse Fourier transducer - Altera Cyclone-2 chip.

Figure 1 shows the functional diagram of the proposed device; figure 2 shows a graph of the source signal; figure 3 shows the Fourier transform of this signal; figure 4 shows a graph of this signal, freed from interference.

As can be seen from the diagram of FIG. 1, the proposed device is a Fourier transducer 1, a correlation filter 2, an inverse Fourier transducer 3, and a result and information processing unit 4 connected in series in the direction of the processed signal.

The Fourier transducer 1 decomposes the received distorted input electric signal into a Fourier series, then the correlation filter 2 sequentially selects harmonics, one of which carries the received information, which will be recorded at the output of the Vertex-4 chip implementing this filter. After that, the inverse Fourier converter 3, having fulfilled its function, will restore the signal freed from interference and transmit it, as well as information about the value of the carrier frequency to the input of the block 4 for processing results and information.

As an example, figure 2 shows a graph of the original signal containing interference. Figure 3 shows its Fourier transform, which corresponds to the sinusoidal time function shown in figure 4

processed by the proposed device, the original signal, freed from interference. The period is 40 μs, which corresponds to f = 25 KHz.

Thus, the use of the proposed device in comparison with the prototype allows you to expand the arsenal of tools used, namely, to implement the device on the elements of digital technology, which results in the unification and miniaturization of the corresponding complex technical solutions, since all the decision blocks can be performed on one chip. In addition, design simplification was achieved in connection with the removal of the reference signal generation circuit and its comparison with the received one.

Claims (1)

A device for determining the carrier frequency of a distorted electrical signal, comprising a received signal correlation analyzer connected to a result and information processing unit, characterized in that the received signal correlation analyzer includes a series-connected Fourier converter, a correlation filter, and an inverse Fourier converter.