RU2440672C1 - Transmitting device of helicopter radar station - Google Patents

Abstract

FIELD: radio engineering. ^ SUBSTANCE: transmitting device of helicopter radar station includes travelling-wave tube (TWT), high-voltage rectifier, voltage divider, collector power source, anode power source, modulator, as well as filament voltage power source, transformer, rectifier, the first switching device, the second switching device, input path, output path, waveguide of input microwave signal W1, waveguide of output microwave signal W2, waveguide connection W3, waveguide connection W4, plug pin of input pulse of transmitter start-up, plug pin for transfer of input alternating supply voltage of phase A, plug pin for supply of input alternating supply voltage of phase B, plug pin for supply of input alternating supply voltage of phase C, and plug pin for supply of input direct supply voltage. At that, modulator consists of the first stabiliser, control diagram, the second stabiliser and switching device. ^ EFFECT: improving operating reliability of transmitting device of helicopter radar station in millimetre wave range so that inconsiderable mass and dimension characteristics can be provided. ^ 1 dwg

Description

The invention relates to the field of radar and can be used in helicopters.

The microwave transmitter is known from the prior art (patent RU No. 2208909, published 2003.07.20, IPC Н04В 1/00, Н05K 7/20). The microwave transmitter contains a master oscillator, a p-i-n attenuator, a decoupling device, a microwave amplifier, a load, a current source, a discriminator, a power source and a modulator, and a closed-loop cooling system. This microwave transmitter can improve operating efficiency by improving the heat removal from the transmitter units and improving the overall dimensions, but does not solve the problem of ensuring operability in the millimeter wave range.

A known microwave transmitter (patent RU No. 2187880, published 2002.08.20, IPC Н03В 9/06). A microwave transmitter between the second output of the master oscillator and the control input p-i-n of the attenuator includes a frequency discriminator and a current source controlled from the discriminator. The current source provides direct current stabilization through the p-i-n attenuator and, as a result, stabilizes the input power and reduces the noise level of the microwave amplifier. The current source is controlled by a discriminator, which generates a frequency-dependent voltage control current p-i-n attenuator. Optimum input power control is automatic and with sufficient speed. The disadvantages of this microwave transmitter include the fact that when obtaining the optimal output power in the frequency range and reducing the level of amplitude and phase noise, it is not possible to improve the overall dimensions of the transmitter.

Closest to the claimed technical essence is a pulsed microwave power amplifier (certificate for utility model No. 16238, published 2000.12.10, IPC H03F 3/58) containing a traveling wave lamp (TWT), the collector terminal of which is connected to the positive bus of the collector source power supply, and the negative bus of the collector power supply is connected to the TWT cathode, the anode power supply. In this case, the negative bus of the anode power source is connected to the positive bus of the collector power source. The positive bus of the anode power source is connected to the positive terminal of the high-voltage stabilizer regulator stage, the negative terminal of which is connected to the housing, and the control input is with the regulating output of the voltage divider, one terminal of which is connected to the TWT cathode and the second to the housing. The common output of the modulator power source is connected to the TWT cathode. The negative bus of the modulator power supply is connected to the output of the first key, and the positive bus is connected to the inputs of the second and third keys. The input of the first key is connected to the output of the third key, the second TWT control grid and, through the isolation diode, with the first TWT control grid, which is connected to the anode of the separation diode, with the output of the second key and through the discharge resistor with the output of the first key. The control input of the first key is connected to the output of the first starting device, the input of which is connected to the output of the switch. The control input of the second key is connected to the output of the second starting device, the input of which is connected to the first input of the switch and the connector of "short" pulses. The control input of the third key is connected to the output of the third starting device, the input of which is connected to the output of the inverter. The inverter input is connected to the trigger connector for long pulses and the second input of the switch. This amplifier pulsed microwave power expands the functionality of the amplifier, but does not improve the overall dimensions of the amplifier and increase its reliability.

The technical result of the proposed technical solution is aimed at improving the reliability of the transmitting device of a helicopter radar station (radar) in the millimeter wavelength range, with the possibility of ensuring minor weight and size characteristics.

The specified technical result is achieved by the fact that the transmitting device of a helicopter radar station contains TWT, a high-voltage rectifier, a voltage divider, a collector power source, an anode power source, and a modulator. Moreover, it differs from the prototype in that it further comprises a glow voltage power source, a transformer, a rectifier, a first switching device, a second switching device, an input path, an output path, an input microwave signal waveguide W1, an output microwave waveguide W2, a waveguide connection W3, waveguide connection W4, contact of the input terminal of the input pulse to start the transmitter, contact of the connector for supplying an input AC voltage of phase A, contact of the connector for supplying an input AC voltage of supply phase B, the contact of the connector for supplying the input alternating voltage of the supply of phase C, the contact of the connector for supplying the input constant voltage of the supply, the modulator consisting of the first stabilizer, control circuit, second stabilizer, switch.

In this case, the first input of the high-voltage rectifier is connected to the third input of the first switching device and the terminal of the connector for supplying an input phase C alternating voltage.

The second input of the high voltage rectifier is connected to the first output of the first switching device. The third input of the high voltage rectifier is connected to the second output of the first switching device. The first output of the high voltage rectifier is connected to the input of the voltage divider. The second output of the high-voltage rectifier is connected to the third input of the modulator. The third output of the high-voltage rectifier is connected to the first input of the modulator.

The first output of the voltage divider is connected to the input of the collector power source. The output of the collector power source is connected to the collector TWT. The second output of the voltage divider is connected to the input of the anode power source. The output of the anode power source is connected to the TWT cathode, with the first output of the glow voltage power source, with the fourth input of the modulator. The contact of the connector for supplying the input phase A alternating voltage is connected to the first input of the first switching device, to the first input of the glow voltage power source, to the second input of the transformer. The contact of the connector for supplying an input AC voltage of phase B is connected to the second input of the first switching device, to the second input of the glow voltage power source, to the first input of the transformer. The second output of the glow voltage power supply is connected to the TWT heater. The first output of the transformer is connected to the first input of the rectifier. The second output of the transformer is connected to the second input of the rectifier. The rectifier output is connected to the input of the second switching device. The output of the second switching device is connected to the output of the modulator and to the TWT control electrode. The second input of the modulator is connected to the terminal of the input pulse of the transmitter start trigger. The fourth input of the first switching device is connected to the terminal connector for supplying an input DC voltage. The waveguide of the input microwave signal W1 is connected to the input of the waveguide connection W3. The output of the waveguide connection W3 is connected to the input of the input path. The output of the input path is connected to the input of the TWT. The TWT output is connected to the input of the waveguide connection W4. The output of the waveguide connection W4 is connected to the input of the output path. The output of the output path is connected to the waveguide of the output signal W2. The TWT anode is connected to the housing. The first input of the modulator is connected to the first input of the first stabilizer. The second input of the modulator is connected to the input of the control circuit. The third input of the modulator is connected to the first input of the second stabilizer. The fourth input of the modulator is connected to the second input of the first stabilizer and to the second input of the second stabilizer. The output of the control circuit is connected to the second input of the switch. The output of the first stabilizer is connected to the first input of the switch. The output of the second stabilizer is connected to the third input of the switch. The output of the switch is connected to the output of the modulator.

The drawing shows a structural diagram of the proposed transmitter, which includes: a traveling wave lamp (TWT) 1, a high voltage rectifier 2, a voltage divider 3, a collector power supply 4, an anode power supply 5, a modulator 6, a power supply voltage 7, a transformer 8, a rectifier 9, second switching device 10, first switching device 11, waveguide connection W4 12, output path 13, input path 14, waveguide of the output microwave signal W2 15, waveguide of the input microwave signal W1 16, waveguide connection W3 17, connector terminal To supply the input AC phase A voltage supply phase A 18, the terminal connector for the input AC phase voltage supply of the phase B 19, the terminal connector for the input AC phase voltage supply of the phase 20, the contact of the helicopter radar transmitter connector for supplying the input DC voltage 21, the terminal contact transmitter input trigger pulse 22.

Modulator 6 contains: a first stabilizer 23, a second stabilizer 24, a control circuit 25, a switch 26.

In this case, the first input of the high-voltage rectifier 2 is connected to the third input of the first switching device 11 and the terminal connector for supplying an input AC voltage of phase C 20. The second input of the high-voltage rectifier 2 is connected to the first output of the first switching device 11. The third input of the high-voltage rectifier 2 is connected to the second the output of the first switching device 11. The first output of the high voltage rectifier 2 is connected to the input of the voltage divider 3. The second output of the high voltage rectifier 2 is connected to the third input modulator 6. The third output of the high-voltage rectifier 2 is connected to the first input of the modulator 6. The first output of the voltage divider 3 is connected to the input of the collector power supply 4. The output of the collector power supply 4 is connected to the collector 4 of TWT 1. The second output of the voltage divider 3 is connected to the input of the anode power source 5. The output of the anode power source 5 is connected to the cathode 1 TWT 1, with the first output of the glow voltage power source 7, with the fourth input of the modulator 6. Contact of the connector for supplying the input AC voltage phase A 18 power supply is connected to the first input of the first switching device 11, to the first input of the glow voltage power supply 7, to the second input of the transformer 8. The terminal connector for supplying the input alternating voltage supply of phase B 19 is connected to the second input of the first switching device 11, with the second input of the power source of the voltage 7, with the first input of the transformer 8. The second output of the power source of the voltage 7 is connected to the heater 3 TWT 1. The first output of the transformer 8 is connected to the first input of the rectifier 9 The second output of the transformer 8 is connected to the second input of the rectifier 9. The output of the rectifier 9 is connected to the input of the second switching device 10. The output of the second switching device 10 is connected to the output of the modulator 6 and to the control electrode 2 TWT 1. The second input of the modulator 6 is connected to the contact of the input connector transmitter start pulse (PPI) 22. The fourth input of the first switching device 11 is connected to the terminal connector for supplying an input DC voltage 21. The waveguide of the input microwave signal W1 16 is connected to the input of the waveguide with connections W3 17. The output of the waveguide connection W3 17 is connected to the input of the input path 14. The output of the input path 14 is connected to the input of the TWT 1. The output of the TWT 1 is connected to the input of the waveguide W4 12. The output of the waveguide connection W4 12 is connected to the input of the output path 13. Output the output path 13 is connected to the waveguide of the output signal W2 15. The anode 5 of the TWT 1 is connected to the housing. The first input of modulator 6 is connected to the first input of the first stabilizer 23. The second input of modulator 6 is connected to the input of the control circuit 25. The third input of modulator 6 is connected to the first input of the second stabilizer 24. The fourth input of modulator 6 is connected to the second input of the first stabilizer 23 and to the second input second stabilizer 24.

The output of the control circuit 25 is connected to the second input of the switch 26. The output of the first stabilizer 23 is connected to the first input of the switch 26. The output of the second stabilizer 24 is connected to the third input of the switch 26. The output of the switch 26 is connected to the output of the modulator 6.

Helicopter radar requires high resolution and negligible weight and size characteristics. Therefore, helicopter radars operate in the eight-millimeter wavelength range. The use of the eight-millimeter wavelength range on helicopter radars makes it possible to detect power wires and meteorological formation hazardous for flight in the low-altitude flight mode. Helicopter radars have a high level of vibration loads, so the transmitter must be resistant to mechanical and climatic factors of group 2U _C GOST RV 20.39.414.1-97. This transmitter provides amplification of the microwave signal in the eight-millimeter wavelength range with an operating frequency band of about 2 GHz, and a low level of intrinsic noise. The commensurability of the geometric dimensions of the elements and components of the transmitter with wavelengths of the microwave range leads to significant changes in the occurring physical phenomena and to significant quantitative and qualitative changes in the electrical properties of the elements used. (Edited by AM Chernushenko. Design of Microwave Devices and Screens. M.: Radio and Communications, 1983, p. 4-8.)

At microwave, the time of flight of electrons between the electrodes becomes comparable with the period of amplified oscillations. During the flight, the alternating voltage at the electrodes manages to noticeably change. This leads to a weakening of the electron flux density, a sharp drop in net power, gain and efficiency. On the microwave, the influence of the inductance of the leads, interelectrode capacitances, losses in the material of the electrodes is very pronounced. (Fedorov N.D. Microwave electronic devices and quantum devices. - M.: ATOMIZDAT, 1979, p. 5-9; MV Vambersky. Microwave transmitting devices. - M.: Higher school, 1984, p. .14-111.)

TWT in terms of the combination of the most important parameters, including the operating frequency bandwidth, gain, average power, efficiency, high frequency and phase stability, low noise, a significant attenuation of the output signal in the pause between pulses, the strength and compactness of the structure, surpass other types of amplification devices Microwave The main advantage of TWT is the ability to receive amplification in a wide band of operating frequencies. (Kukarin S.V. Electronic microwave devices. - M.: Radio and communications, 1981, p. 64-100; Katsman Yu.A. Microwave devices. - M.: Higher school, 1983, p.196 -264; Edited by M. Skolnik, Radar Handbook, Vol. 3. M: Soviet Radio, 1979, pp. 7-127.) Therefore, a small-sized pulsed TWT of type O of the eight-millimeter wavelength range was used as the output amplifier stage of the transmitter. with dynamic electronic flow control, low noise, with a spiral deceleration system to obtain a wide band of operating frequencies, resistant to impact Mechanical Protection and climatic factors 2Y group _C RV GOST 20.39.414.1-97. In TWT, the rigidity of the structure is significantly increased. The overall dimensions of the TWT are not more than 205 × 65.5 × 37 mm, the mass is not more than 660 g, and the output power is not less than 18 W.

To amplify the input microwave signal in the TWT, it is necessary that the electron stream in the TWT created by the electron gun interacts with the input electromagnetic field of the microwave signal for a long time. For long-term interaction of electrons with an electromagnetic field, the synchronism condition must be observed:

v _about > v _f , by 5-10%,

Where

v _f - phase wave velocity,

v _o is the initial electron velocity.

This leads to very stringent requirements for the operation of pulsed TWTs of the millimeter wavelength range (Vambersky M.V. Microwave Transmitting Devices. - M.: Higher School, 1984, p. 14-111).

The reliability of the transmitter to a large extent depends on the reliable operation of the TWT. One of the main requirements for ensuring the reliable operation of TWTs is: introduction of TWT protection schemes, ensuring the inclusion of TWTs. Failure to comply with the above conditions leads to a violation of the focusing conditions of the electron beam and the TWT to fail (OST 110348-86; Fedorov ND Electronic microwave devices and quantum devices.- M .: ATOMIZDAT, 1979, p. 62-78; Minaev MI Radio-frequency transmitters of super-high frequencies. - Minsk, Higher School, 1978, p.40-93).

The transmitting device of a helicopter radar operates as follows. From the waveguide input W1 16 through the waveguide connection W3 17, the microwave signal is fed to the input of the input path 14. From the output of the input path 14, the microwave signal is fed to the input 1 TWT 1, the output 1 TWT 1 is amplified microwave signal through the waveguide connection W4 12, the output path 13 , the waveguide W2 15 goes to the output of the transmitter (Vambersky M.V. Microwave Transmitting Devices. - M.: Higher School, 1984, p. 404-430; edited by A.M. Chernushenko Design of microwave devices and screens. M. : Radio and communications, 1983, pp. 78-207; Edited by M. Skolnik, Radar Handbook, vol. 3. M .: Soviet radio, 197 9 g., P. 400-442). For stable TWT operation, it is required that the value of the rise time constant of the blocking voltage on the control electrode is less than the rise time constant on the retardation system (OST 11 0348-86). It is necessary to provide a delay in switching on the voltage at the anode with respect to the blocking voltage at the TWT 1 control electrode. This requirement in transmitting devices is fulfilled by the use of two high-voltage transformers that turn on and off at the same time. But high-voltage transformers have a large weight and dimensions, and a helicopter radar requires insignificant mass and dimensional characteristics of the transmitter. To ensure this mode, it is proposed to use one high-voltage transformer and the proposed circuit solution.

When the radar is switched on, a three-phase voltage of 200 V, 400 Hz and 27 V is applied to the transmitter input. Initially, two phases of the voltage of 200 V, 400 Hz, FA 18 and 200 V, 400 Hz, FV 19 are supplied to the power source of the glow voltage 7 and transformer 8, and the voltage 200 V, 400 Hz FS 20 - to the first input of a high-voltage rectifier 2. Using a power source of a filament voltage 7, a filament voltage is generated, which is fed to the cathode of the TWT 1. On the transformer 8 and rectifier 9, a blocking voltage is generated by the control electrode - Upr _z.1 which through the second comm device Station 10 is fed to the control electrode 2 TWT 1 before applying the anode voltage and pre-closes TWT 1.

A voltage of 27 V is supplied to the first switching device 11, which allows the passage of two phases of voltage 200 V, 400 Hz FA and 200 V, 400 Hz PV through the first switching device 11 to the high-voltage rectifier 2 and it starts to work.

Then, a voltage of 27 V (with a delay relative to the voltage of 200 V, 400 Hz) is supplied to the transmitter from the radar power supply to the first switching device 11, which allows the passage of two phases of the voltage 200 V, 400 Hz FA and 200 V, 400 Hz PV through the first device switching 11 to the high-voltage rectifier 2 and it starts to work.

A high-voltage rectifier 2 through a voltage divider 3, a collector power supply 4, an anode power supply 5 provides the required value of the anode, collector voltage on the TWT 1, while the collector power supply 4 through a voltage divider 3 and a high-voltage rectifier 2 is connected in series with the anode power source. This allows you to ensure the operation of the collector power source 4 with energy recovery (Katsman Yu.A. Microwave devices. - M .: Higher school, 1983, from 165, 196-264).

A stabilized high voltage is supplied to the cathode 1 of the TWT 1 relative to the anode 5 of the TWT 1, which is structurally connected to the transmitter housing.

From the high-voltage rectifier 2 also supply voltages for the first 23 and second 24 stabilizers of the modulator 6. The first stabilizer 23 generates a stabilized voltage of the control electrode - Uupr, which opens TWT 1. The second stabilizer 24 forms the passport value of the locking voltage across the control electrode - Uupr. _{2 while} Ucont _z.2> Ucont _z.1. The voltages Uupr and Uprp.2 _are supplied to the switch 26. The input of the control circuit 25 is supplied from the terminal of the input pulse of the transmitter start-up (UHF) 22 pulse of the UHF to control the switch 26. The switch 26, depending on the pulse of the UHF, supplies Uupr _h.2 or Uupr (in the presence of SSI - opens TWT 1, in the absence of SSI - closes TWT 1). In the absence of an ISF, the voltage Upr ₃ from the output of the modulator 6 closes the second switching device 10 and enters the control electrode 2 TWT 1, closing the TWT 1. The pulse of the ISP is fed to the transmitter input with a delay relative to the voltage supply time of 27 V. As a result, the turn-on delay is provided voltage at the anode with respect to the blocking voltage at the control electrode LBV 1 (Kostikov V.G. Power sources of high voltage REA. - M.: Radio and communications, 1986, p.1-95; N. Naivelt G.S. Power sources REA. - M.: Radio and St. bond, 1986, at s.121-208, J. Kar. Designing and manufacturing of electronic equipment. M .: Mir, 1980, at s.299-319).

In case of failure of the high-voltage rectifier 2 disappears Ucont _z.2, so called second switching unit 10 and delivers to the control electrode of TWT 1 2 Ucont _z.1 voltage, for locking TWT 1, preventing its failure (Katzman YA Devices Microwave - M .: Higher School, 1983, p.196-264). Otherwise, due to the lack of blocking voltage at the control electrode 2, TWT 1 can go into continuous mode and fail.

High-voltage rectifier 2 consists of a high-voltage transformer, several rectifiers on semiconductor diodes, which rectify AC voltage and smoothing filters, which reduce ripple of rectified voltages. The divider consists of a set of resistors and capacitors. (Nivevelt G.S. Power sources of REA. - M.: Radio and communications, 1986, p. 121-208; Edited by M. Skolnik. Handbook on radar. T.3. M.: Soviet radio, 1979, p.118-127; V.N. Gaevich. Radio engineering. M.: Military publishing house of the Ministry of Defense of the USSR, p.204-218).

The control circuit 25 provides control of the switch 26 and the transfer of the SPD from the common wire of the modulator to the voltage potential of the anode, providing isolation from the potential. The switch 26 consists of two electronic keys. In the first switching device 11, switching is carried out using a relay, and in the second switching device 10 using a diode (Vambersky M.V. Transmitting devices Microwave. - M.: Higher school, 1984, p. 384-390; J. Kar. Design and manufacture of electronic equipment. M: Mir, 1980, p. 82-103, 258-270).

Improvement of technical parameters is achieved through the use of a low-voltage transformer 8, a rectifier 9, and a second switching device 10 to generate the locking voltage of the TWT 1 - Upr _s.1 at the initial moment of supplying a three-phase voltage of 200 V, 400 Hz to the transmitter and in case of failure of the high-voltage rectifier.

This makes it possible at the moment of switching on the transmitter to provide a delay in switching on the voltage at the anode with respect to the blocking voltage at the TWT 1 control electrode, as well as to prevent the failure of the expensive TWT in the event of a high-voltage rectifier failure. Improvement of technical parameters is carried out due to:

- the use of an eight-millimeter wavelength range for the transmitter, which makes it possible to detect power wires and meteorological hazards for helicopters in low-altitude flight mode;

- protection of expensive TWT in the event of a high-voltage rectifier failure in the transmitter;

- the use of a low-voltage transformer 8, rectifier 9, second switching device 10 to generate the locking voltage of the TWT 1 - Upr _s.1 at the initial moment of supplying the three-phase voltage of 200 V, 400 Hz to the transmitting device of the helicopter radar, that is, before applying voltage to the anode, which increases the reliability of the TWT, while maintaining minor weight and size characteristics.

Claims (1)

A transmitting device for a helicopter radar station containing a traveling wave lamp (TWT), a high voltage rectifier, a voltage divider, a collector power supply, an anode power supply, a modulator, characterized in that it further comprises a glow voltage power supply, a transformer, a rectifier, a first switching device, and a second switching device, input path, output path, waveguide of the input microwave signal W1, waveguide of the output microwave signal W2, waveguide connection W3, waveguide connection W4, circuit t of the input terminal of the input pulse for starting the transmitter, the terminal connector for supplying the input alternating voltage of the phase A power supply, the terminal terminal for supplying the input alternating voltage of the phase B, the terminal terminal for supplying the input alternating voltage of the phase C, the terminal terminal for supplying the input constant voltage, the modulator consists of a first stabilizer, a control circuit, a second stabilizer, a switch, while the first input of the high-voltage rectifier is connected to the third input of the first device two switching inputs and a terminal connector for supplying an input AC voltage of phase C supply, the second input of the high-voltage rectifier is connected to the first output of the first switching device, the third input of the high-voltage rectifier is connected to the second output of the first switching device, the first output of the high-voltage rectifier is connected to the input of the voltage divider, second output a high-voltage rectifier is connected to the third input of the modulator, the third output of the high-voltage rectifier is connected to the first input of the modulator, the first the stroke of the voltage divider is connected to the input of the collector power supply, the output of the collector power supply is connected to the collector of TWT, the second output of the voltage divider is connected to the input of the anode power supply, the output of the anode power supply is connected to the cathode of the TWT, with the first output of the glow voltage power supply, with the fourth input modulator, the contact of the connector for supplying an input AC phase A voltage is connected to the first input of the first switching device, to the first input of the voltage power source Akala, with the second input of the transformer, the contact of the connector for supplying the input alternating voltage of the phase B power supply is connected to the second input of the first switching device, to the second input of the glow voltage power supply, to the first input of the transformer, the second output of the glow voltage power supply is connected to the TWT heater, the first the transformer output is connected to the first input of the rectifier, the second output of the transformer is connected to the second input of the rectifier, the output of the rectifier is connected to the input of the second switching device, the output of the second switching device is connected to the output of the modulator and to the TWT control electrode, the second input of the modulator is connected to the connector terminal of the input pulse of the transmitter start, the fourth input of the first switching device is connected to the connector terminal for supplying the input DC voltage, the waveguide of the input microwave signal W1 is connected to the input waveguide connection W3, the output of the waveguide connection W3 is connected to the input of the input path, the output of the input path is connected to the input of the TWT, the output of the TWT is connected to the input of the wave one connection W4, the output of the waveguide connection W4 is connected to the input of the output path, the output of the output path is connected to the waveguide of the output signal W2, the TWT anode is connected to the housing, the first input of the modulator is connected to the first input of the first stabilizer, the second input of the modulator is connected to the input of the control circuit, the third the modulator input is connected to the first input of the second stabilizer, the fourth modulator input is connected in parallel with the second input of the first stabilizer and the second input of the second stabilizer, the output of the control circuit is Inonii the second input of the switch, the first regulator outlet is connected to the first input of the switch, the second regulator output is connected to the third input of the switch, the switch output is connected with the output of the modulator.