RU2547444C1 - Transceiver - Google Patents

Abstract

FIELD: radio engineering, communication.

SUBSTANCE: result is achieved by filtering an interference signal as a result of synchronous frequency tuning of the driving generator in a transmitting channel and heterodyne frequency for a first mixer in a receiving channel, as well as by generating a heterodyne signal for a second mixer in the receiving channel as a result of conversion in a third mixer of the heterodyne signal and the signal of the driving generator of the transmitting channel to obtain a second heterodyne signal at a differential frequency.

EFFECT: noise-immunity of the transceiver from targeted frequency interference.

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Description

The present invention relates to short-range radar devices and can be used as a transceiver (PDU) for a coherent-pulse (pulse-Doppler) type radio range finder, the principle of which is described in [1, pp. 120-121].

Known "Method and device for data collection, detection and (or) analysis of at least one object" [2], "Method and device for generating RF signals to determine the distance and / or speed of the object" [3]. The closest analogue to the proposed device is the "Method and device for generating RF signals to determine the distance and / or speed of the object."

The prototype [3] contains the first self-oscillator (AG) 1, the first directional coupler (HO), the second AG 2, the second HO, the first mixer (M 1), the first input of which is connected to the first output of the first NO, and the second input is connected to the first output the second BUT, a bandpass filter (PF) 7, the input of which is connected to the output of the first mixer M 1, the first amplitude control device (AMC) 8, the first input of which is connected to the output of the PF 7, a transmitting antenna 20, the input of which is connected to the output of the first AMC 8 , receiving antenna 22, low noise amplifier (LNA) 14, the input of which is Inonii yield receiving antenna 22, a second mixer M2, a first input of which is connected to the second output of the first NO, and a second input connected to the output of the LNA 14, intermediate frequency amplifier (IF amplifier) 14 ¹ whose input is coupled to an output of the second mixer M2, the second UAA 15, the first input of which is connected to the output of the UPCH 14 ¹ , the third NO, the input of which is connected to the output of the second UAA 15, the third mixer M 3, the first input of which is connected to the second output of the second NO, and the second input is connected to the first output of the third NO Doppler frequency signal amplifier 16, the input of which is connected to the output of the third mixer M 3, and the output is a coherent output 23 of the device, an amplitude detector (HELL) 17, the input of which is connected to the second output of the third BUT, a pulse broadband amplifier (EAR) 18 [4, p.693], input which is connected to the output of the HELL 17, and the output 22 is an incoherent output of the device, the first modulator 12, the output of which is connected to the second input of the second UAA 15, the second modulator 13, the output of which is connected to the second input of the first UAA 8, control unit (BU) 11, whose output is connected to the inputs of the first the first 12 and second 13 modulators.

The prototype [3] of the coherent-pulse type works with double frequency conversion in the receiver. At the output of the first mixer M 1, as a result of mixing highly stable sinusoidal signals of the first AG 1 with a frequency f _{G1 of the} second AG 2 with a frequency f _G2 , sinusoidal signals of total and difference frequencies (f _G1 ± f _G2 ) are formed. The carrier frequency signal f _C = (f _G1 + f _G2 ) is allocated at the output of the PF 7, after the first ASU 8, the radio pulses through the antenna transmitting 20 are emitted into space. The delayed radio pulses from the output of the receiving antenna 22 through the LNA 14 are fed to the second input of the second mixer M 2, the first input of which receives a local oscillation signal with a frequency f _G1 . From the output of the second mixer M 2, the radio pulses with the first intermediate frequency f _Г2 are fed to the input of the amplifier 14 ¹ and then through the third НО 15 from the first output to the second input of the third mixer М 3, the heterodyne signal with the frequency f _Г2 is fed to the second input of it. At the output of the third mixer M 3, after the second frequency conversion, delayed video pulses are emitted relative to the emitted radio pulses for the time the signal propagates in space to the target and back, the amplitude of which varies according to the cosine law with the Doppler frequency. The video pulses are amplified by a Doppler frequency amplifier 16 and are supplied to the coherent output 23 of the device. At the output of HELL 17, delayed video pulses are allocated, which are fed to the input of the EAR 18 and then to the incoherent output 22 of the device. The disadvantage of the above device should be attributed to the lack of noise immunity from interference-oriented interference-frequency interference of any type.

The aim of the invention is to provide noise immunity PPU from aiming frequency interference.

This goal is achieved by the fact that in the PUF containing the first AG, the first BUT, the input of which is connected to the output of the first AG, the first mixer (Cm), the first input of which is connected to the first output of the first BUT, the second AG, the second BUT, the input of which is connected to the output of the second AG, the transmitting antenna, the first UAA, the first IFA, the second CM, EAR, the output of which is connected to the output of the control panel, the control unit, the input of which is connected to the first input of the control panel, the first PF, the transmitting antenna, LNA, the second CC, the third See, additionally introduced a valve whose input is connected to the second output of the first BUT, a phase shifter (PV), the first input of which is connected to the output of the valve, the second input is connected to the third output of the control unit, and the output is connected to the first input of the first AC, power amplifier (PA), the input of which is connected to the output of the first AC, and the output is connected to the input of the transmitting antenna, a low-pass filter (LPF), the input of which is connected to the output of the second CM, and the output is connected to the input of the EAR, the second PF, the input of which is connected to the second output of the second BUT, and the output is connected to the second input of the third Cm, the third PF, the input of which is connected to the output of the receiving antenna oh, a protective device (memory), the input of which is connected to the output of the third PF, the first attenuator (At), the first input of which is connected to the output of the memory, the second input is connected to the fourth input of the control panel, and the output is connected to the input of the LNA, the fourth PF, the input of which is connected with the output of the second AC, and the output is connected to the first input of the third CM, the fifth PF, the input of which is connected to the output of the third CM, the second amplifier, the input of which is connected to the output of the fifth PF, the second At, the first input of which is connected to the output of the second IF, the second input connected to the fifth input of the PPU, and the output is connected nen with the first input of the second CM, and the input of the first amplifier is connected to the output of the first CM, and the output is connected to the second input of the second CM, the first output of the control unit is connected to the second input of the first AC, and the second output is connected to the second input of the second AC, the input of the first PF is connected with the first output of the second BUT, and the output is connected to the second input of the first CM, the input of the first AG is connected to the second input, and the input of the second AG is connected to the third input of the control panel, the LNA output is connected to the first input of the second AC.

The proposed PPU coherent-pulse type, by analogy with the prototype, works with double frequency conversion in the receiving channel. The first voltage-controlled oscillator (AGGN) operates at the carrier frequency as a pathogen in the transmitting channel to generate the emitted radio signal. The second AGUN works in the receiving channel to form the reference signal of the third cm at a frequency exceeding the frequency of the emitted radio signal by the value of the first intermediate frequency. After the first conversion, the radio pulses at the output of the third Cm are transferred to the first intermediate frequency. The reference signal for the second CM at the first intermediate frequency is formed after converting the signals of the first AGUN and the second AGUN at the output of the first See. After the second conversion, the radio pulses at the first intermediate frequency are converted at the output of the second CM into video pulses. The principle of phase formation of the reference signal of the second cm as the phase difference of the second AGUN and the first AGUN during their synchronous tuning allows you to keep the first intermediate frequency of the converted radio pulses constant and provides coherent processing of the received radio signal. Interference immunity from interference-frequency-sensing interference is ensured as a result of synchronous tuning of the frequency of the first and second AGUN so that the interference signal is output outside the passband of the fifth PF at the output of the third cm and a low-pass filter (low-pass filter) at the output of the second See. A comparative analysis with the prototype shows that the claimed device is characterized by the presence of new blocks, the connections between the blocks. Thus, we can conclude that the claimed device meets the criteria of "novelty" and "significant differences".

Figure 1 shows the block diagram of the PPU. Figure 2 - diagrams explaining the operation of the PUF.

PPU contains a transmitting antenna 1, UM 2, the output of which is connected to the input of the transmitting antenna 1, the first UUA 3, the output of which is connected to the input of the UM 2, FV 4, the output of which is connected to the first input of the first UUA 3, valve 5, the output of which is connected to the first input of the PV 4, the first HO 6, the second output of which is connected to the input of the valve 5, the first Cm 7, the first input of which is connected to the second output of the first HO 6, the first IF 8, the input of which is connected to the output of the first Cm 7, second Cm 9, the second input of which is connected to the output of the first UPCH 8, low-pass filter 10, the input of which is connected to the output of the second cm 9, ears 11, the input of which is connected to the output of the low-pass filter 10, and the output is connected to the output of the control panel, control unit 12, the input of which is connected to the first input of the control panel, the first output is connected to the second input of the first UUA 3, and the third output is connected to the second the input FV 4, the first AGUN 13, the input of which is connected to the second input of the PPU, and the output is connected to the input of the first HO 6, the second AGUN 15, the input of which is connected to the third input of the CPU, and the output is connected to the input of the second HO 16, the first PF 14, the input of which is connected to the first output of the second HO 16, and the output is connected to the second input of the first See 7, the second PF 17, the input of which is connected to the second output of the second HO 16, the receiving antenna 18, the third PF 19, the input of which is connected to the output of the receiving antenna 18. ZU 20, the input of which is connected to the output of the third PF 19, the first attenuator (At ) 21, the first input of which is connected to the output of the memory device 20, and the second input is connected to the fourth input of the control panel, LNA 22, the input of which is connected to the output of the first At 21, the second CMA 23, the first input of which is connected to the output of the LNA 22, and the second input is connected with the second output of BU 12, the fourth PF 24, the input of which is connected by the output of the second UUA 23, tr circuit 25, the first input of which is connected to the output of the fourth PF 24, and the second input is connected to the output of the second PF 17, the fifth PF 26, the input of which is connected to the output of the third Sm 25, the second UHF 27, the input of which is connected to the output of the fifth PF 26, the second At 28, the first input of which is connected to the output of the second UPCH 27, the second input is connected to the fifth input of the control panel, and the output is connected to the first input of the second CM 9.

PPU works as follows. The first AGUN 13 with frequency tuning by a varicap [4, p. 335] is controlled by the external voltage coming from the second input of the control panel from the processing unit (BO) of the radio range finder. The phase of the signal at the output of AGUN 13 is written as:

Where

π = 180 °;

f _N is the lower frequency value of the first AGUN 13;

k = 0, 1, 2, ... - the number of letters, the number of letters is determined by the band and discrete frequency tuning AGUN 13;

Δf - discrete frequency tuning AGUN 13;

t is the time;

Ф ₀₁ - the initial phase of the signal of the first AGUN 13.

In the future, for simplicity of exposition, the constant phase incursion in the elements of the transmitting and receiving paths will be neglected and only the initial phases of the signals of the first AGUN 13 and the second AGUN 15 will be taken into account. A sinusoidal signal from the output of the first AGUN 13 is fed to the input of the first HO 6 [5, p. 130- 137] and then from the second output of HO 6 through valve 5 [4, p. 277] to the first input of discrete PV 4 [6, p. 128]. The input BU 12 from the first output of the PPU receives a periodic sequence of rectangular pulses (figa). Under the action of the control voltage (figb), coming from the third output of the control unit 12, the phase of the signal at the output of the PV 4 switches from period to period within (0-π / 2). The phase of the signal at the output of the discrete PV 4 is written in the form:

Where

m is the number of the repetition period of rectangular pulses;

T _P - the repetition period of rectangular pulses;

T _And - the duration of the rectangular pulses.

The phase-manipulated signal from the output of the PV 4 is fed to the first input of the first AS 3 [5, p.148-157]. The control unit 12 generates a control signal of the required amplitude and duration (Fig.2c), which from the first output of the control unit 12 is supplied to the second input of the first CID 3. At the output of the first CID 3, a periodic sequence of radio pulses of the required duration and power is formed. The radio pulses from the output of the first UAA 3 are fed to the input of the PA 2 with external excitation [4, p. 339-346]. From the output of the PA 2, the radio pulses of the required power are fed to the input of the transmitting antenna 1 and radiated into space. The radio signal at the output of the transmitting antenna 1 is written as:

Where

U _C is the amplitude of the radio signal;

In the future, for simplicity of presentation, we will assume the transmission coefficients of the elements of the receiving path equal to 1. The radio pulses reflected from the target from the output of the receiving antenna 18 through the third PF 19, designed to protect the receiver from powerful out-of-band interference, are fed to the input of the memory 20 [5, p. 165-169]. From the output of the memory 20, the radio pulses arrive at the first input of the first At 21 [5, p. 158-164] and then to the input of the LNA 22. The memory 20 is designed to protect the LNA 22 from powerful interference in the operating frequency range, and the first AT 21 is designed to prevent overload of LNA 22 with a limited interference signal from the output of the charger 20. The second input of the first At 21 receives the control voltage from the fourth input of the control panel, which smoothly adjusts the power of the radio pulses and the noise at the output of At 21. The radio pulses from the output of the first At 21 go to the first input second AMC 23, to the second input of which the pulses of the blank (FIG. 2d) from the second output of the control unit 12 coincide in time with the control pulses (FIG. 2c) of the first ACM 3. At the moment of receipt of the pulses of the form, the second ACM 23 is locked, while overloading of the receiving path emitted radio pulses that enter the receive path due to the final isolation between the transmitting 1 and receiving 18 antennas. The radio pulses from the output of the second UAA 23 through the fourth PF 24, designed to eliminate the influence on the sensitivity of the receiving path of noise LNA 22 in the range of specular frequencies, are fed to the first input of the third cm 25. We write the radio signal at the first input of the third cm 25 in the form:

Where

R is the range to the target;

V - speed of approach (-) or removal (+) of the target;

c is the speed of light.

From the output of the second AGUN 15 through the second HO 16 and the second PF 17 to the second input of the third Cm 25 as a heterodyne signal with a phase determined by the ratio:

Where

f _IF1 is the first intermediate frequency;

F ₀₂ - the initial phase of the second AGUN 15.

Using relations (2, 6, 8), the converted signal at the output of the third cm 25 is written in the form:

The radio pulses at the first intermediate frequency through the fifth PF 26 and the second UPCH 27 are fed to the first input of the second adjustable At 28, the second input of which receives control voltage from the fifth input of the PPU, under the influence of which the power of the radio pulses at the output of the second At 28 is continuously adjusted. Fifth PF 26 is designed to attenuate the interference signal when the frequency of the second AGUN 15 is tuned to a level that excludes the overload of the second IF 27. Under the influence of an external control voltage, the attenuators At 21 and At 28, which are input t into the automatic gain control loop, smoothly adjust the power level of the received radio pulses in such a way as to maintain the amplitude of the signal at the output of the USHI 11 constant over the entire range of measured ranges. From the output of the second At 28, the radio pulses at the first intermediate frequency are fed to the first input of the second Cm 9, the second input of which as a heterodyne signal is received from the output of the first Cm 7 through the first amplifier 8. The signal of the first intermediate frequency at the output of the first Cm 7 is generated by mixing the heterodyne signal supplied to the second input of CM 7 from the output of the second AGUN 15 through the second HO 16 and the first PF 14, as well as the signal from the output of the first AGUN 13 supplied to the first input of the second Sm 7 from the first output of the first HO 6. The first PF 14 and second PF 17 are tuned in the operating frequency range of the second AGUN 15 and are designed to attenuate to the required minimum level of the leaky signal of the first AGUN 13 from the first input of the first Sm 7 to the second input of the third Sm 25. Using relations (1, 8), the phase of the heterodyne signal entering the second the input of the second cm 9, we write in the form:

Using the relations (9, 10), the converted signal at the output of the second cm 9 is written in the form:

Using relations (7, 11), the signal at the output of the second cm 9 after the transformations is written in the form:

Where

At the output of the second Cm 9, the received signal can be considered as two periodic sequences of video pulses with a repetition period of 2 T _P , the envelope of which changes respectively according to the cosine (Fig.2d) law for odd periods and the sinusoidal (Fig.2e) law for even periods. The presence of two sequences of video pulses, the envelope of which is in quadrature, allows signal processing not to lose contact with a slowly moving target when the Doppler frequency is close to zero. The resulting signal (Fig.2g) from the output of the second Cm 9 through the low-pass filter 10 and ears 11 is fed to the output of the PUF and then to the BO of the radio range finder. The low-pass filter 10 is designed to attenuate the power of the interference signal tuned in frequency to a level not exceeding the intrinsic noise at the output of the ears 11.

Thus, in the proposed PPU, in comparison with the prototype, the frequencies of the first AGUN 13 and the second AGUN 15 are synchronously tuned, while the interference is removed from the passband of the receiving channel, as a result of which the PPU is immune to interference from interference-oriented interference frequencies.

Bibliography

1. Handbook of electronic systems, volume 2. Edited by the candidate of technical sciences B.Kh. Krivitsky. Moscow, Energy, 1979.

2. “Invention of the countries of the world” No. 3 - 2007, p. 85. “A method and apparatus for collecting data, detecting and (or) analyzing at least one object” (US Application No. 978132 of 10/29/2004).

3. “Invention of the countries of the world” No. 8 - 2007, p. 75. “A method and apparatus for generating RF signals for determining the distance and (or) the speed of an object” ”(US Application No. 491089 of 03/29/2004).

4. “Radio engineering”. "Encyclopedia". Edited by Yu.L. Mazora, E.A. Machussky, V.I. The truth. Moscow, Dodeka XXI Publishing House, 2002.

5. A.V. Morozov, P.N. Naumov, A.N. Nyrtsov. Microwave Devices and Antennas, Part 1. Radiotekhnika Publishing House, Moscow - 2009.

6. N.T. Bova, P.A. Stukalo, V.A. Temples. Microwave control devices. Publishing house "Technique", Kiev - 1973.

Claims (1)

A transceiver comprising a first oscillator, a first directional coupler, the input of which is connected to the output of the first oscillator, a first mixer, the first input of which is connected to the first output of the first directional coupler, a second oscillator, a second directional coupler, the input of which is connected to the output of the second oscillator, a transmitting antenna , a first amplitude control device, a first intermediate frequency amplifier, a second mixer, a broadband pulse amplifier, the output of which connected to the output of the transceiver device, a control unit, the input of which is connected to the first input of the transceiver device, a first bandpass filter, a transmitting antenna, a low noise amplifier, a second amplitude control device, a third mixer, characterized in that the input of the first intermediate frequency amplifier is connected to the output of the first mixer and the output is connected to the second input of the second mixer, the first output of the control unit is connected to the second input of the first amplitude control device, and the second output is connected is connected to the second input of the second amplitude control device, the input of the first bandpass filter is connected to the first output of the second directional coupler, and the output is connected to the second input of the first mixer, the input of the first oscillator is connected to the second input, and the input of the second oscillator is connected to the third input of the transceiver, output low-noise amplifier is connected to the first input of the second amplitude control device, an additional valve is introduced, the input of which is connected to the second output of the first directional of the second coupler, a phase shifter, the first input of which is connected to the output of the valve, the second input is connected to the third output of the control unit, and the output is connected to the first input of the first amplitude control device, the power amplifier, the input of which is connected to the output of the first amplitude control device, and the output is connected to the input of the transmitting antenna, a low-pass filter, the input of which is connected to the output of the second mixer, and the output is connected to the input of the broadband pulse amplifier, the second band-pass filter, the input of which is connected with the second output of the second directional coupler, and the output is connected to the second input of the third mixer, the third bandpass filter, the input of which is connected to the output of the receiving antenna, a protective device, the input of which is connected to the output of the third bandpass filter, the first attenuator, the first input of which is connected to the output of the protective device , the second input is connected to the fourth input of the transceiver, and the output is connected to the input of a low-noise amplifier, the fourth band-pass filter, the input of which is connected to the output of the second device amplitude control, and the output is connected to the first input of the third mixer, the fifth bandpass filter, the input of which is connected to the output of the third mixer, the second intermediate frequency amplifier, the input of which is connected to the output of the fifth bandpass filter, the second attenuator, the first input of which is connected to the output of the second amplifier intermediate frequency, the second input is connected to the fifth input of the transceiver, and the output is connected to the first input of the second mixer.

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