High-power low-noise-floor radio frequency feed channel and use method

Abstract

The invention relates to a high-power low-noise-floor radio frequency feed channel and a use method, the radio frequency feed channel comprises a switch band elimination filter assembly and a code word plate, the switch band elimination filter assembly is arranged on a radiation antenna, the code word plate is correspondingly plugged with a control computer, and the code word plate is connected with the switch band elimination filter assembly through a line; the code word board is formed by arranging an input interface, an FPGA, a power supply module and an output interface on a circuit board; the input interface adopts a standard LVDS interface to be connected with a control computer, and the FPGA converts the frequency code, the bandwidth code and the band elimination range of the band elimination filter into a multi-way switch control word to control the switching of the multi-way switch; the switch band elimination filter group comprises a circuit board, the circuit board is sequentially provided with a power amplifier and a pair of multi-way switches, a plurality of band elimination filters are arranged between the multi-way switches, and the left and right ends of the circuit board are respectively provided with a radio frequency input interface and a radio frequency output interface; and the base noise in the active radar working frequency band of the radio frequency feed channel is effectively reduced.

Description

Technical Field

[0001] The present invention relates to the field of semi-physical radio frequency simulation testing, and in particular to a high-power and low-noise radio frequency feeding channel and a use method thereof. Background Art

[0002] The RF simulation antenna array is an important component of the semi-physical RF simulation test system. It is mainly used to radiate the RF signal generated by the signal environment simulation subsystem into the microwave darkroom, and simulate the continuous movement of the radar target in azimuth and elevation by controlling the amplitude and phase of the RF signal under the control of the semi-physical RF simulation test system control computer.

[0003] At present, the antenna array RF feed channels of the semi-physical simulation test system are all broadband designs. According to the technical indicators of the test seeker, a power amplifier is added to the corresponding position of the RF feed channel to meet the signal power requirements of the test seeker. For the active and passive composite guidance seeker, its active part has the characteristics of high receiving antenna gain and high receiver sensitivity. Therefore, in the simulation test, the output signal power requirements of the antenna array RF feed channel are low, but the base noise power generated by the antenna array RF feed channel needs to be strictly controlled to ensure that the base noise signal does not affect the detection of the target signal by the active part; while the passive part of the active and passive composite guidance seeker has relatively low receiving antenna array gain and relatively low receiver sensitivity, so the base noise power control requirements for the output signal of the antenna array RF feed channel are not high, but in order to ensure that the target signal can be detected, the antenna array RF feed channel is required to output a relatively high power signal. While the existing RF feed channel amplifies the signal, it will also generate a large base noise signal, which cannot simultaneously meet the detection of the target signal by the active and passive parts. In order to meet the test needs of the passive part of the subject, the signal needs to be amplified. However, when the channel amplifies the signal, it also amplifies the background noise signal, which affects the detection of the target signal by the active part. In order to meet the test needs of the active part, the power of the background noise signal must be strictly controlled, and the channel gain design cannot be too large, which will result in a small output signal power and fail to meet the test needs of the passive part.

[0004] In view of the above reasons, a high-power and low-noise RF feeding channel and a method of using the same are now developed. Summary of the invention

[0005] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a high-power, low-noise radio frequency feeding channel and a method for using the same. A power amplifier and a switch band-stop filter group are added to the output end of the coarse control unit of the radio frequency simulation antenna array feeding channel. According to the working frequency band of the active part, the band-stop filters of different frequency bands are selected by using a switch, so that the radio frequency feeding channel forms different gains in different frequency bands. The active part has a low gain, so that the base noise power can be effectively controlled. A larger gain is formed in the remaining frequency bands to complete the amplification of the signal power, and the passive part provides a high-power output signal, so that the test needs of the active and passive composite guidance seeker can be met, and the base noise in the working frequency band of the radio frequency feeding channel active radar can be effectively reduced. At the same time, it can be ensured that a sufficiently large output signal power can be achieved outside the band, so that the system can complete the performance identification of the active and passive radar seekers, and the method of adding a codeword conversion board in the control circuit realizes the high-power signal output and low-noise functions of the radio frequency feeding channel, and ensures that the signal power in other frequency bands meets the needs of the passive radar for signal reconnaissance and identification.

[0006] In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a high-power low-noise radio frequency feeding channel, the radio frequency feeding channel includes a switch band-stop filter component and a codeword board, the switch band-stop filter is arranged on the radiation antenna, the codeword board is correspondingly plugged with the control computer, and the codeword board is connected with the switch band-stop filter component through a line; the codeword board is composed of an input interface, an FPGA, a power module and an output interface arranged on a circuit board; the input interface adopts a standard LVDS interface to connect with the control computer, receives the control signal sent by the semi-physical radio frequency simulation system through the LVDS and converts it into a signal that the FPGA can receive; the FPGA converts the frequency code, the bandwidth code and the band-stop range of the band-stop filter into a multi-way switch control word, and latches the control word, and the control word sent by the FPGA is converted by the output interface module into a TTL interface voltage, thereby controlling the multi-way switch to switch; The switch band-stop filter group includes a circuit board, on which a power amplifier and a pair of multi-way switches are arranged in sequence from left to right, and multiple band-stop filters are arranged between the pair of multi-way switches from top to bottom. A radio frequency input interface and a radio frequency output interface are arranged at the left and right ends of the circuit board respectively, and the pair of multi-way switches are electrically connected to the power amplifier, multiple band-stop filters, and the radio frequency output interface respectively; the output interface of the codeword board is connected to the pair of multi-way switches through a line, and the radio frequency input interface is electrically connected to the power amplifier.

[0007] Furthermore, the center frequency and bandwidth of the band-stop filter are determined according to actual needs, the in-band suppression is -30dBc, the out-of-band flatness is ±3dB, and the frequency points between two adjacent band-stop filters are connected to each other.

[0008] Furthermore, the RF input interface and RF output interface use standard female SMA interfaces, with a voltage standing wave ratio of 2:1 and a maximum input power of 0dBm; a standard TTL interface is used between the multi-way switch and the codeword board, with a low voltage of 0.2V and a high voltage of 4.6V.

[0009] The invention discloses a method for using a high-power and low-noise radio frequency feeding channel. A radiation source signal simulator outputs a radar radiation source simulation signal for evaluating the signal sorting and identification capability of a passive radar. A target echo simulator outputs a radar target echo signal for evaluating the target detection and identification capability of an active radar. The two signals are combined into one signal by a combiner and then simultaneously input into a switch band-stop filter group. During the test, the frequency of the radar radiation source is set and the out-of-band frequency point of the corresponding band-stop filter is selected. The input radar radiation source simulation signal and radar target echo signal are first amplified by a power amplifier to ensure that the output signal power can meet the requirements of the passive radar for signal sorting and identification. The multi-way switches in the switch band-stop filter group realize synchronous switching under the control of the same control word, so that the radio frequency signal passes through the band-stop filter corresponding to the working frequency of the active radar, and the band-stop filter reduces the base noise power in the working frequency band of the active radar. At the same time, it can ensure that the out-of-band signal passes with a small attenuation, which can meet the requirements of the passive radar for signal power.

[0010] The beneficial effects of the present invention are as follows: The present invention is based on the combined construction of existing mature commercial devices, and by adding a power amplifier and a switch band-stop filter group to the output end of the coarse control unit of the RF simulation antenna array feeding channel, according to the working frequency band of the active part, the switch is used to select the band-stop filters of different frequency bands, so that the RF feeding channel forms different gains in different frequency bands, the active part has a low gain, thereby effectively controlling the base noise power, and forming a larger gain in the remaining frequency bands to complete the amplification of the signal power, while the passive part provides a larger output signal, thereby being able to meet the testing needs of the active and passive composite guidance seeker, effectively reducing the base noise within the working frequency band of the active radar of the RF feeding channel, and at the same time ensuring that a sufficiently large output signal power can be achieved outside the band, ensuring that the system can complete the performance identification of the active and passive radar seekers, and adding a codeword conversion board in the control circuit to realize the high-power signal output and low-noise functions of the RF feeding channel, ensuring that the signal power in other frequency bands meets the needs of passive radar for signal reconnaissance and identification; the parts not described in detail in the present invention are existing common technologies. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The present invention will be further described below in conjunction with the accompanying drawings: Figure 1 It is a block diagram of the high-power low-noise RF feed channel; Figure 2 This is a schematic diagram of the installation position of the switch band-stop filter group. DETAILED DESCRIPTION

[0012] The present invention is further described in detail below in conjunction with embodiments and specific implementation modes: Example 1

[0013] like Figure 1 As shown, a high-power low-noise radio frequency feeding channel, the radio frequency feeding channel includes a switch band-stop filter component and a codeword board, the switch band-stop filter is arranged on the radiation antenna, the codeword board is correspondingly plugged with the control computer, and the codeword board is connected to the switch band-stop filter component through a line; the codeword board is composed of an input interface, an FPGA, a power module and an output interface arranged on a circuit board; the input interface adopts a standard LVDS interface to connect with the control computer, receives the control signal sent by the semi-physical radio frequency simulation system through the LVDS and converts it into a signal that the FPGA can receive; the FPGA converts the frequency code, the bandwidth code and the band-stop range of the band-stop filter into a multi-way switch control word, and latches the control word, and the control word sent by the FPGA is converted by the output interface module into a TTL interface voltage, thereby controlling the multi-way switch to switch; The switch band-stop filter group includes a circuit board, on which a power amplifier and a pair of multi-way switches are arranged in sequence from left to right, and multiple band-stop filters are arranged between the pair of multi-way switches from top to bottom. A radio frequency input interface and a radio frequency output interface are arranged at the left and right ends of the circuit board respectively, and the pair of multi-way switches are electrically connected to the power amplifier, multiple band-stop filters, and the radio frequency output interface respectively; the output interface of the codeword board is connected to the pair of multi-way switches through a line, and the radio frequency input interface is electrically connected to the power amplifier.

[0014] Furthermore, the center frequency and bandwidth of the band-stop filter are determined according to actual needs, the in-band suppression is -30dBc, the out-of-band flatness is ±3dB, and the frequency points between two adjacent band-stop filters are connected to each other.

[0015] Furthermore, the RF input interface and RF output interface use standard female SMA interfaces, with a voltage standing wave ratio of 2:1 and a maximum input power of 0dBm; a standard TTL interface is used between the multi-way switch and the codeword board, with a low voltage of 0.2V and a high voltage of 4.6V. Example 2

[0016] like Figure 2As shown, a method for using a high-power, low-noise-bottom RF feeding channel is provided, wherein a radiation source signal simulator outputs a radar radiation source simulation signal for evaluating the signal sorting and identification capability of a passive radar; a target echo simulator outputs a radar target echo signal for evaluating the target detection and identification capability of an active radar, and the two signals are combined into one signal by a combiner and simultaneously input into a switch band-stop filter group. During the test, the frequency of the radar radiation source is set, and the out-of-band frequency point of the corresponding band-stop filter is selected; the input radar radiation source simulation signal and the radar target echo signal are first amplified by a power amplifier to ensure that the output signal power can meet the requirements of the passive radar for signal sorting and identification; the multi-way switches in the switch band-stop filter group are synchronously switched under the control of the same control word, so that the RF signal passes through the band-stop filter corresponding to the working frequency of the active radar, and the band-stop filter reduces the base noise power in the working frequency band of the active radar; at the same time, it can ensure that the out-of-band signal passes with a small attenuation, which can meet the requirements of the passive radar for signal power.

[0017] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A high-power, low-noise RF feed channel, characterized in that: The RF feeding channel includes a switch band-stop filter component and a codeword board. The switch band-stop filter is arranged on the radiation antenna. The codeword board is correspondingly plugged into the control computer. The codeword board is connected to the switch band-stop filter component through a line. The codeword board is composed of an input interface, an FPGA, a power module and an output interface arranged on a circuit board. The input interface adopts a standard LVDS interface to connect to the control computer, receives a control signal sent by a semi-physical RF simulation system through LVDS and converts it into a signal that the FPGA can receive. The FPGA converts the frequency code, bandwidth code and the band-stop range of the band-stop filter into a multi-way switch control word, and latches the control word. The control word sent by the FPGA is converted into a TTL interface voltage after being converted by the output interface module, thereby controlling the multi-way switch to switch. The switch band-stop filter group includes a circuit board, on which a power amplifier and a pair of multi-way switches are arranged in sequence from left to right, a plurality of band-stop filters are arranged between the pair of multi-way switches from top to bottom, a radio frequency input interface and a radio frequency output interface are arranged at the left and right ends of the circuit board respectively, and the pair of multi-way switches are electrically connected to the power amplifier, the plurality of band-stop filters, and the radio frequency output interface respectively; The output interface of the codeword board is connected to a pair of multi-way switches through lines, and the radio frequency input interface is electrically connected to the power amplifier.

2. A high-power, low-noise RF feed channel according to claim 1, characterized in that: The center frequency and bandwidth of the band-stop filter are determined according to actual needs, the in-band suppression is -30dBc, the out-of-band flatness is ±3dB, and the frequency points between two adjacent band-stop filters are connected to each other.

3. The high-power, low-noise RF feed channel according to claim 1, characterized in that: The RF input interface and RF output interface adopt standard female SMA interface, with voltage standing wave ratio of 2:1 and maximum input power of 0dBm; the multi-way switch and the codeword board adopt standard TTL interface, with low voltage of 0.2V and high voltage of 4.6V.

4. A method for using the high-power, low-noise RF feed channel as described in claim 1, characterized in that: The radiation source signal simulator outputs a radar radiation source simulation signal, which is used to assess the passive radar's signal sorting and identification capabilities; the target echo simulator outputs a radar target echo signal, which is used to assess the active radar's target detection and identification. The two signals are combined into one signal through a combiner and then simultaneously input into the switch band-stop filter group. During the test, the frequency of the radar radiation source is set, and the out-of-band frequency of the corresponding band-stop filter is selected; the input radar radiation source simulation signal and radar target echo signal are first amplified by a power amplifier to ensure that the output signal power can meet the passive radar's signal sorting and identification requirements; the multi-way switches in the switch band-stop filter group are synchronously switched under the control of the same control word, so that the radio frequency signal passes through the band-stop filter corresponding to the active radar's operating frequency, and the band-stop filter reduces the base noise power within the active radar's operating frequency band; at the same time, it can ensure that the out-of-band signal passes with less attenuation, which can meet the passive radar's signal power requirements.

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