CN117579092A

CN117579092A - Multipath V-band signal sampling method and V-band multichannel receiver

Info

Publication number: CN117579092A
Application number: CN202311683398.9A
Authority: CN
Inventors: 徐婕
Original assignee: Nanjing Yuanzheng Information Technology Co ltd
Current assignee: Nanjing Yuanzheng Information Technology Co ltd
Priority date: 2023-12-09
Filing date: 2023-12-09
Publication date: 2024-02-20

Abstract

The invention discloses a multipath V-band signal sampling method and a V-band multichannel receiver, wherein the multipath V-band signal sampling method comprises the following steps: sampling and isolating the echo radio frequency signals through a directional coupler, sending the isolated echo radio frequency signals to an A/D converter for analog-to-digital conversion, outputting a first signal, and sending the first signal to a low-noise amplifier module; filtering noise in the first signal through a low noise amplifier module, and outputting a second signal; the second signal and the local oscillation signal are mixed by the mixing module to generate a third signal, and if the signal frequency band of the third signal is larger than 50GHz, the third signal is sent to the intermediate frequency module to be processed to generate an intermediate frequency signal; otherwise, amplifying the signal by an RF amplifier, and then sending the amplified signal to an intermediate frequency module for processing to generate an intermediate frequency signal; sending the intermediate frequency signal to a signal processing module for signal processing; the invention can realize accurate sampling of multipath V-band signals.

Description

Multipath V-band signal sampling method and V-band multichannel receiver

Technical Field

The invention relates to the technical field of receivers, in particular to a multipath V-band signal sampling method and a V-band multichannel receiver.

Background

Along with the rapid development of modern communication technology, the receiver sets up higher index requirements, the design and implementation processes of receivers with different types and different wave bands are greatly different, and the existing microwave receiver mainly has two ways to realize multichannel observation: the first is to carry out detection frequency scanning and multichannel time-sharing observation by frequency hopping and frequency conversion of the vibration source to a fixed intermediate frequency; and the second is to adopt a filter bank to realize multichannel frequency division and radio frequency direct detection mode for multichannel simultaneous observation, and compared with the first sweep frequency microwave radiometer receiver, the multichannel parallel filter receiver allows the atmospheric temperature and humidity to be measured simultaneously, and the measurement time is reduced to the greatest extent.

However, in the design of the existing microwave receiver, in order to reduce noise of the receiver, a bandpass filter is usually placed before a low noise amplifier, so that a significant insertion loss occurs in the bandpass filter, but the noise of the receiver is deteriorated, the phase resolution is low, and the consistency and stability of the measurement signal are poor.

Disclosure of Invention

This section is intended to outline some aspects of embodiments of the invention and to briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section as well as in the description summary and in the title of the application, to avoid obscuring the purpose of this section, the description summary and the title of the invention, which should not be used to limit the scope of the invention.

The present invention has been made in view of the above-described problems occurring in the prior art.

Therefore, the invention provides a wave band multichannel receiver design method, which can reduce the noise of the receiver and enhance the stability of the receiver.

In order to solve the technical problems, the invention provides the following technical scheme that: sampling and isolating the echo radio frequency signals through a directional coupler, sending the isolated echo radio frequency signals to an A/D converter for analog-to-digital conversion, outputting first signals, and sending the first signals to a low-noise amplifier module; filtering noise in the first signal through a low noise amplifier module, and outputting a second signal; the second signal and the local oscillation signal are mixed by the mixing module to generate a third signal, and if the signal frequency band of the third signal is larger than 50GHz, the third signal is sent to the intermediate frequency module to be processed to generate an intermediate frequency signal; otherwise, the signal is sent to an RF amplifier for amplification, namely the signal intensity of the radio frequency band of the third signal is enhanced, and then the amplified signal is sent to an intermediate frequency module for processing to generate an intermediate frequency signal; sending the intermediate frequency signal to a signal processing module for signal processing to obtain a V-band digital signal; wherein the return loss of the RF amplifier is less than-10 dB.

As a preferable scheme of the multi-path V-band signal sampling method, the invention comprises the following steps: the A/D converter includes: the A/D converter consists of an analog signal sampling unit, an analog signal quantizing unit, a digital signal encoding unit and an STC time sensitivity control unit, wherein the analog signal sampling unit, the analog signal quantizing unit and the digital signal encoding unit are sequentially connected, the output end of the digital signal encoding unit is connected with the STC time sensitivity control unit, and the STC time sensitivity control unit provides a clock signal with high precision and low jitter for the digital signal encoding unit so as to synchronize the output of the digital signal encoding unit; the output end of the STC time sensitivity control unit is configured to be compatible with the input port of the low noise amplifier module and can be directly connected.

As a preferable scheme of the multi-path V-band signal sampling method, the invention comprises the following steps: the low-noise amplification module comprises an LM324 amplifier, an OTL amplifier, a variable attenuator, a filter, a power supply, a plurality of capacitors and a plurality of resistors; the output end of the filter is connected with the input end of the LM324 amplifier through a coupling capacitor, the output end of the LM324 amplifier is connected with the input end of the variable attenuator through a coupling capacitor, the output end of the variable attenuator is connected with the input end of the OTL amplifier through a coupling capacitor, and the emitters of the OTL amplifier are connected with resistors; the power supply pin is connected with a decoupling capacitor, and a local current path is provided for the LM324 amplifier and the OTL amplifier respectively.

As a preferable scheme of the multi-path V-band signal sampling method, the invention comprises the following steps: further comprises: the filter comprises a frequency divider, an oscillator and at least one tunable filter, the tunable filter is used for suppressing in-band interference signals with the radio frequency band larger than 100GHz in the first signal, and then the frequency of the signals output by the tunable filter is reduced by the frequency divider so as to reduce the frequency of the signals, and the signals are fed back to the oscillator to generate a second signal; wherein the center frequency of the tunable filter is set to 60GHz; the low-band cut-off frequency was set to 50GHz and the in-band return loss was set to 20dB.

As a preferable scheme of the multi-path V-band signal sampling method, the invention comprises the following steps: the mixing module comprises a coupler, a tunable oscillator, a balance bridge and a matched load; the output end of the coupler is connected with the input end of the tunable oscillator through a matching load, and the output end of the tunable oscillator is connected with the balance bridge through a coupling capacitor; selecting an IF channel through a coupler and a tunable oscillator to convert the second signal into an RF frequency band, mixing with a local oscillator signal, inputting the mixing result into a balance bridge, and outputting a third signal; the balance bridge consists of four Schottky barrier diodes which are connected end to form a ring shape.

As a preferable scheme of the multi-path V-band signal sampling method, the invention comprises the following steps: the intermediate frequency module comprises an 8-channel power divider, a square-rate detector, an IF band-pass filter and an operational amplifier; the output end of the 8-channel power divider is connected with the input end of the square-rate detector, the input end of the square-rate detector is connected with the input end of the IF band-pass filter, and the output end of the IF band-pass filter is connected with the input end of the operational amplifier; the 8-channel power divider divides the third signal or the signal amplified by the RF amplifier into 8 frequency bands, inputs the 8 frequency bands into the square-rate detector for primary amplification, removes interference signals through the IF band-pass filter, and finally performs secondary amplification through the operational amplifier to output intermediate frequency signals.

As a preferable scheme of the multi-path V-band signal sampling method, the invention comprises the following steps: the signal processing module comprises two FPGA chips and a DSP signal processor; the two FPGA chips are connected with the DSP signal processor through buses, bit quantization selection, matrix transposition and down-conversion processing of signal channels and frequency channels are carried out on intermediate frequency signals through the FPGA chips, and then filtering processing is carried out through the DSP signal processor, so that V-band digital signals are obtained.

As a preferred embodiment of the V-band multichannel receiver of the invention, wherein: comprising the following steps: a directional coupler configured to perform sampling and isolation of the echo signals and transmit the isolated echo radio frequency signals to the a/D converter; the A/D converter is configured to perform analog-to-digital conversion on the isolated echo radio frequency signal, output a first signal and send the first signal to the low-noise amplifier module; the A/D converter consists of an analog signal sampling unit, an analog signal quantizing unit, a digital signal encoding unit and an STC time sensitivity control unit, wherein the analog signal sampling unit, the analog signal quantizing unit and the digital signal encoding unit are sequentially connected, the output end of the digital signal encoding unit is connected with the STC time sensitivity control unit, and the STC time sensitivity control unit provides a clock signal with high precision and low jitter for the digital signal encoding unit so as to synchronize the output of the digital signal encoding unit; the low-noise amplification module is configured to filter noise in the first signal and output a second signal; the frequency mixing module is configured to perform frequency mixing of the second signal and the local oscillation signal to generate a third signal, wherein if the signal frequency band of the third signal is greater than 50GHz, the third signal is sent to the intermediate frequency module; otherwise, send to the RF amplifier; an RF amplifier configured to amplify the third signal having a frequency band less than or equal to 50GHz, i.e., to enhance the signal strength of the radio frequency band of the third signal, and then to transmit the amplified signal to the intermediate frequency module; wherein the return loss of the RF amplifier is less than-10 dB; an intermediate frequency module configured to perform processing of the third signal or the signal pair amplified by the RF amplifier, generating an intermediate frequency signal; the intermediate frequency module comprises an 8-channel power divider, a square-rate detector, an IF band-pass filter and an operational amplifier; the output end of the 8-channel power divider is connected with the input end of the square-rate detector, the input end of the square-rate detector is connected with the input end of the IF band-pass filter, and the output end of the IF band-pass filter is connected with the input end of the operational amplifier; the 8-channel power divider is configured to divide a third signal or a signal amplified by the RF amplifier into 8 frequency bands and input the 8 frequency bands to the square-rate detector for primary amplification, the IF bandpass filter is configured to remove interference signals in the signal output by the square-rate detector, and the operational amplifier is configured to perform secondary amplification on the signal output by the IF bandpass filter and output an intermediate frequency signal; the signal processing module is configured to perform signal processing on the intermediate frequency signal to obtain a V-band digital signal; the signal processing module comprises two FPGA chips and a DSP signal processor; the two FPGA chips are connected with the DSP signal processor through buses, the FPGA chips are configured to execute bit quantization selection on intermediate frequency signals, matrix transposition and down-conversion processing of signal channels and frequency channels, and the DSP signal processor is configured to execute filtering processing on signals output by the FPGA chips to obtain V-band digital signals.

As a preferred embodiment of the V-band multichannel receiver of the invention, wherein: the low-noise amplification module comprises an LM324 amplifier, an OTL amplifier, a variable attenuator, a filter, a power supply, a plurality of capacitors and a plurality of resistors; the output end of the filter is connected with the input end of the LM324 amplifier through a coupling capacitor, the output end of the LM324 amplifier is connected with the input end of the attenuator through a coupling capacitor, the output end of the variable attenuator is connected with the input end of the OTL amplifier through a coupling capacitor, and the emitters of the OTL amplifier are connected with resistors; the power supply pin is connected with a decoupling capacitor, and a local current path is respectively provided for the LM324 amplifier and the OTL amplifier; the filter includes a frequency divider configured to perform frequency division of a signal output from the tunable filter and feed back to the oscillator to generate a second signal, an oscillator, and at least one tunable filter configured to perform suppression of an in-band interference signal in the first signal having a radio frequency band greater than 100 GHz.

As a preferred embodiment of the V-band multichannel receiver of the invention, wherein: the mixing module comprises a coupler, a tunable oscillator, a balance bridge and a matched load; the output end of the coupler is connected with the input end of the tunable oscillator through a matching load, and the output end of the tunable oscillator is connected with the balance bridge through a coupling capacitor; the coupler and the tunable oscillator are used for selecting an IF channel so as to convert the second signal into an RF frequency band, mix the second signal with a local oscillator signal, input the mixing result into the balance bridge and output a third signal; the balance bridge consists of four Schottky barrier diodes which are connected end to form a ring shape.

The invention has the beneficial effects that: according to the invention, each module of the receiver is designed according to the V-band frequency band range, and the noise of the receiver can be greatly reduced through multistage filtering and amplification, so that the accurate sampling of multipath V-band signals is realized.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are needed in the description of the embodiments will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the present invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art. Wherein:

fig. 1 is a flow chart of a method for sampling a multi-path V-band signal according to a first embodiment of the present invention;

fig. 2 is a schematic structural diagram of a radio frequency quadrature coupler according to a first embodiment of the present invention.

Detailed Description

So that the manner in which the above recited objects, features and advantages of the present invention can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to the embodiments, some of which are illustrated in the appended drawings. All other embodiments, which can be made by one of ordinary skill in the art based on the embodiments of the present invention without making any inventive effort, shall fall within the scope of the present invention.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, but the present invention may be practiced in other ways other than those described herein, and persons skilled in the art will readily appreciate that the present invention is not limited to the specific embodiments disclosed below.

Further, reference herein to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic can be included in at least one implementation of the invention. The appearances of the phrase "in one embodiment" in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments.

While the embodiments of the present invention have been illustrated and described in detail in the drawings, the cross-sectional view of the device structure is not to scale in the general sense for ease of illustration, and the drawings are merely exemplary and should not be construed as limiting the scope of the invention. In addition, the three-dimensional dimensions of length, width and depth should be included in actual fabrication.

Also in the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "upper, lower, inner and outer", etc. are based on the orientation or positional relationship shown in the drawings, are merely for convenience of describing the present invention and simplifying the description, and do not indicate or imply that the apparatus or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present invention. Furthermore, the terms "first, second, or third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

The terms "mounted, connected, and coupled" should be construed broadly in this disclosure unless otherwise specifically indicated and defined, such as: can be fixed connection, detachable connection or integral connection; it may also be a mechanical connection, an electrical connection, or a direct connection, or may be indirectly connected through an intermediate medium, or may be a communication between two elements. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art.

Example 1

Referring to fig. 1 to 2, a first embodiment of the present invention provides a multi-path V-band signal sampling method, including:

s1: the echo radio frequency signals are sampled and isolated through the directional coupler, the isolated echo radio frequency signals are sent to the A/D converter for analog-to-digital conversion, a first signal is output, and the first signal is sent to the low-noise amplifier module.

The A/D converter consists of an analog signal sampling unit, an analog signal quantizing unit, a digital signal encoding unit and an STC time sensitivity control unit, wherein the analog signal sampling unit, the analog signal quantizing unit and the digital signal encoding unit are sequentially connected, the output end of the digital signal encoding unit is connected with the STC time sensitivity control unit, and the STC time sensitivity control unit provides high-precision and low-jitter clock signals for the digital signal encoding unit, so that the output of the digital signal encoding unit is synchronous, and the time delay is effectively reduced.

The output end of the STC time sensitivity control unit is configured to be compatible with the input port of the low noise amplifier module and can be directly connected.

S2: and filtering noise in the first signal through the low noise amplifier module, and outputting a second signal.

In processing the echo rf signal, if the receiver is ideal, no noise is generated, but in practice, it is impossible to perform a complete linear processing, and a part of the noise is always generated, so that when designing the receiver, the noise needs to be filtered as much as possible during the signal processing.

In the embodiment, the noise in the first signal is filtered by designing the low-noise amplifying module, so that the sensitivity of the system is improved; specifically, the low-noise amplification module is composed of an LM324 amplifier, an OTL amplifier, a variable attenuator, a filter, a power supply, a plurality of capacitors and a plurality of resistors.

The output end of the filter is connected with the input end of the LM324 amplifier through a coupling capacitor, and preferably, the output end of the filter is connected with the coupling capacitor, so that the direct current component in the first signal can be removed; the LM324 amplifier is a low cost four-way operational amplifier with true differential inputs; in single power applications, the four-way op-amp may operate at supply voltages as low as 3.0V or as high as 32V, with quiescent currents around one fifth of MC1741 (per amplifier), common mode input range including negative power, and no external biasing components are required in many applications.

The filter comprises a frequency divider, an oscillator and at least one tunable filter, the tunable filter is used for suppressing in-band interference signals with the radio frequency band larger than 100GHz in the first signal, and then the frequency of the signals output by the tunable filter is reduced by the frequency divider so as to reduce the frequency of the signals, and the signals are fed back to the oscillator to generate a second signal; wherein the center frequency of the tunable filter is set to 60GHz; the low-band cut-off frequency was set to 50GHz and the in-band return loss was set to 20dB.

The output end of the LM324 amplifier is connected with the input end of the variable attenuator through a coupling capacitor, the output end of the variable attenuator is connected with the input end of the OTL amplifier through a coupling capacitor, and the gain control of the LM324 amplifier and the OTL amplifier is realized through the variable attenuator.

Preferably, the emitters of the OTL amplifier are connected with resistors, so as to provide bias for the OTL amplifier, balance the potential of the input end and prevent the influence of coupling noise on the circuit; the power supply pin is connected with a decoupling capacitor, and a local current path is respectively provided for the LM324 amplifier and the OTL amplifier so as to reduce the peak value of current impact in the circuit and reduce the propagation of switching noise in the circuit.

S3: and mixing the second signal with the local oscillation signal by utilizing a mixing module to generate a third signal.

The embodiment further filters image noise existing in the receiver by designing a mixing module, and specifically, the mixing module comprises a coupler, a tunable oscillator, a balance bridge and a matched load; specific design criteria are shown in table 1.

Table 1: design index of the mixing module.

Design index	Local oscillator signal frequency band	Mirror image suppression degree	Local oscillator signal power
				Numerical value	V-band	＞30dB	12dBm

Referring to fig. 2, the coupler used in this embodiment is a radio frequency quadrature coupler, a is an input end, B and C are output ends, and D is an isolation end; preferably, the radio frequency orthogonal coupler is a broadband coupling device, the frequency bandwidth can be 1.5 octaves, and the isolation in the V wave band can reach-30 dB.

The output end of the coupler is connected with the input end of the tunable oscillator through a matching load, and the output end of the tunable oscillator is connected with the balance bridge through a coupling capacitor; the working principle of the mixing module is as follows: selecting an IF channel through a coupler and a tunable oscillator to convert the second signal into an RF frequency band, mixing with a local oscillator signal, inputting the mixing result into a balance bridge, and outputting a third signal;

the balance bridge consists of four Schottky barrier diodes which are connected end to form a ring shape, and the Schottky barrier diodes are manufactured by utilizing metal-semiconductor (M-S) contact characteristics.

S4: if the signal frequency band of the third signal is larger than 50GHz, the third signal is sent to an intermediate frequency module for processing to generate an intermediate frequency signal; otherwise, the signal is sent to an RF amplifier for amplification, namely the signal intensity of the radio frequency band of the third signal is enhanced, and then the amplified signal is sent to an intermediate frequency module for processing to generate an intermediate frequency signal.

The intermediate frequency module in this embodiment is connected in a cascade manner, so that the frequency selectivity in the V-band bandwidth is better than 0.2%, and specifically, the intermediate frequency module 500 includes an 8-channel power divider, a square-rate detector, an IF band-pass filter and an operational amplifier; the output end of the 8-channel power divider is connected with the input end of the square-rate detector, the input end of the square-rate detector is connected with the input end of the IF band-pass filter, and the output end of the IF band-pass filter is connected with the input end of the operational amplifier.

The 8-channel power divider divides a third signal with a signal frequency band greater than 50GHz or a signal amplified by the RF amplifier into 8 frequency bands (5.2-5.4 GHz, 5.5-5.7 GHz, 5.8-6.0 GHz, 6.1-6.3 GHz, 6.4-6.6 GHz, 6.7-6.9 GHz, 7.0-7.2 GHz and 7.3-7.5 GHz), inputs the third signal or the signal amplified by the RF amplifier into the square-rate detector for primary amplification, removes interference signals through the IF band-pass filter, and finally carries out secondary amplification through the operational amplifier to output intermediate frequency signals.

In order to obtain a sufficiently large signal strength, the present embodiment amplifies an unsatisfactory signal with an RF amplifier having a return loss of less than-10 dB.

S5: and sending the intermediate frequency signal to a signal processing module for signal processing to obtain a V-band digital signal.

The signal processing module comprises two FPGA chips and a DSP signal processor; the two FPGA chips are connected with the DSP signal processor through buses, bit quantization selection, matrix transposition and down-conversion processing of signal channels and frequency channels are carried out on intermediate frequency signals through the FPGA chips, and then filtering processing is carried out through the DSP signal processor, so that V-band digital signals are obtained.

Preferably, a digital signal processing core with the sampling frequency up to 600MHz is provided in the FPGA chip, so that the dynamic range of signal processing is greatly enlarged, and the high-speed processing of the DSP signal processor is facilitated.

Example 2

This embodiment differs from the first embodiment in that a V-band multi-channel receiver is provided, comprising,

a directional coupler configured to perform sampling and isolation of the echo signals and transmit the isolated echo radio frequency signals to the a/D converter;

the A/D converter is configured to perform analog-to-digital conversion on the isolated echo radio frequency signal, output a first signal and send the first signal to the low-noise amplifier module; the A/D converter consists of an analog signal sampling unit, an analog signal quantizing unit, a digital signal encoding unit and an STC time sensitivity control unit, wherein the analog signal sampling unit, the analog signal quantizing unit and the digital signal encoding unit are sequentially connected, the output end of the digital signal encoding unit is connected with the STC time sensitivity control unit, and the STC time sensitivity control unit provides high-precision and low-jitter clock signals for the digital signal encoding unit so as to synchronize the output of the digital signal encoding unit.

The low-noise amplification module is configured to filter noise in the first signal and output a second signal; specifically, the low-noise amplification module comprises an LM324 amplifier, an OTL amplifier, a variable attenuator, a filter, a power supply, a plurality of capacitors and a plurality of resistors;

specifically, the output end of the filter is connected with the input end of the LM324 amplifier through a coupling capacitor, preferably, the output end of the filter is connected with the coupling capacitor, so that direct current components in signals can be removed, the output end of the LM324 amplifier is connected with the input end of the attenuator through the coupling capacitor, the output end of the variable attenuator is connected with the input end of the OTL amplifier through the coupling capacitor, gain control of the LM324 amplifier and the OTL amplifier is realized through the variable attenuator, the emitters of the OTL amplifier are connected with resistors to provide bias for the OTL amplifier, the potential of the input end is balanced, and the influence of coupling noise on a circuit is prevented; the power supply pin is connected with a decoupling capacitor, and a local current path is provided for the LM324 amplifier and the OTL amplifier respectively, so that the peak value of current impact in the circuit is reduced, and the propagation of switching noise in the circuit is reduced.

The filter includes a frequency divider configured to perform frequency division of a signal output from the tunable filter and feed back to the oscillator to generate a second signal, an oscillator, and at least one tunable filter configured to perform suppression of an in-band interference signal in the first signal having a radio frequency band greater than 100 GHz.

The frequency mixing module is configured to perform frequency mixing of the second signal and the local oscillation signal so as to inhibit image noise and generate a third signal, wherein if the signal frequency band of the third signal is greater than 50KHz, the third signal is sent to the intermediate frequency module; otherwise, send to the RF amplifier; specifically, the mixing module comprises a coupler, a tunable oscillator, a balance bridge and a matched load; the output end of the coupler is connected with the input end of the tunable oscillator through a matching load, and the output end of the tunable oscillator is connected with the balance bridge through a coupling capacitor; the coupler and the tunable oscillator are used for selecting an IF channel so as to convert the second signal into an RF frequency band, mix the second signal with a local oscillator signal, input the mixing result into the balance bridge and output a third signal; the balance bridge consists of four Schottky barrier diodes which are connected end to form a ring shape.

An RF amplifier configured to amplify the third signal having a frequency band less than or equal to 50GHz, i.e., to enhance the signal strength of the radio frequency band of the third signal, and then to transmit the amplified signal to the intermediate frequency module; in order to obtain a sufficiently large signal strength, the present embodiment uses the RF amplifier 400 to amplify an unsatisfactory signal, wherein the return loss of the RF amplifier is less than-10 dB.

An intermediate frequency module configured to perform processing of the third signal or the signal pair amplified by the RF amplifier, generating an intermediate frequency signal; the intermediate frequency module comprises an 8-channel power divider, a square-rate detector, an IF band-pass filter and an operational amplifier, and is preferably connected in a cascading manner, so that the frequency selectivity in the v-band bandwidth is better than 0.2%; the output end of the 8-channel power divider is connected with the input end of the square-rate detector, the input end of the square-rate detector is connected with the input end of the IF band-pass filter, and the output end of the IF band-pass filter is connected with the input end of the operational amplifier; the 8-channel power divider is configured to divide a third signal with a signal frequency band greater than 50GHz or a signal amplified by the RF amplifier into 8 frequency bands and input the 8 frequency bands to the square-rate detector for primary amplification, the IF band-pass filter is configured to remove interference signals in the signal output by the square-rate detector, and the operational amplifier is configured to perform secondary amplification on the signal output by the IF band-pass filter and output an intermediate frequency signal.

The signal processing module is configured to perform signal processing on the intermediate frequency signal to obtain a V-band digital signal; the signal processing module comprises two FPGA chips and a DSP signal processor; the two FPGA chips are connected with the DSP signal processor through buses, the FPGA chips are configured to execute bit quantization selection on intermediate frequency signals, matrix transposition and down-conversion processing of signal channels and frequency channels, and the DSP signal processor is configured to execute filtering processing on signals output by the FPGA chips to obtain V-band digital signals.

Example 3

In order to verify and explain the technical effects adopted in the method, the embodiment selects the traditional V-band multichannel receiver and the V-band multichannel receiver designed by adopting the invention to carry out comparison test, and the test results are compared by a scientific demonstration means to verify the true effects of the invention.

The traditional V-band multichannel receiver has obvious insertion loss due to the fact that the filter is directly accessed into the input end of the traditional V-band multichannel receiver, so that the receiver has certain noise, the signal processing result is affected, and the stability is poor.

In order to verify that the invention has higher stability, strong anti-interference capability and larger gain compared with the traditional V-band multichannel receiver, in the embodiment, echo radio frequency signals are respectively input into the traditional V-band multichannel receiver and the V-band multichannel receiver designed by the invention, simulation tests are carried out through a spectrometer and a vector network analyzer, the noise coefficient is adopted to represent the noise size inside the receiver, and the simulation results are shown in the following table.

Table 2: and comparing the noise coefficient of the receiver with the gain test result.

Table 3: and comparing the receiver image rejection degree test results.

Frequency of	Conventional V-band multichannel receiver	V-band multichannel receiver designed by the invention
			50.0GHz	－32.6	－27.3
50.5GHz	－31.8	－25.7
			51.0GHz	－31.4	－23.8
51.5GHz	－30.2	－22.1
			52.0GHz	－29.5	－20.6
52.5GHz	－29.0	－20.2
			53.0GHz	－28.9	－19.4
53.5GHz	－28.7	－18.5

As can be seen from tables 2 and 3, the V-band multichannel receiver designed by the invention has smaller noise coefficient and higher mirror image suppression degree and can better suppress noise compared with the traditional V-band multichannel receiver.

It should be noted that the above embodiments are only for illustrating the technical solution of the present invention and not for limiting the same, and although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solution of the present invention may be modified or substituted without departing from the spirit and scope of the technical solution of the present invention, which is intended to be covered in the scope of the claims of the present invention.

Claims

1. A method for sampling a multipath V-band signal, comprising:

sampling and isolating the echo radio frequency signals through a directional coupler, sending the isolated echo radio frequency signals to an A/D converter for analog-to-digital conversion, outputting first signals, and sending the first signals to a low-noise amplifier module;

filtering noise in the first signal through a low noise amplifier module, and outputting a second signal;

the second signal and the local oscillation signal are mixed by the mixing module to generate a third signal, and if the signal frequency band of the third signal is larger than 50GHz, the third signal is sent to the intermediate frequency module to be processed to generate an intermediate frequency signal; otherwise, the signal is sent to an RF amplifier for amplification, namely the signal intensity of the radio frequency band of the third signal is enhanced, and then the amplified signal is sent to an intermediate frequency module for processing to generate an intermediate frequency signal;

sending the intermediate frequency signal to a signal processing module for signal processing to obtain a V-band digital signal;

wherein the return loss of the RF amplifier is less than-10 dB.

2. The method for sampling a multi-path V-band signal according to claim 1, wherein said a/D converter comprises:

the A/D converter consists of an analog signal sampling unit, an analog signal quantizing unit, a digital signal encoding unit and an STC time sensitivity control unit, wherein the analog signal sampling unit, the analog signal quantizing unit and the digital signal encoding unit are sequentially connected, the output end of the digital signal encoding unit is connected with the STC time sensitivity control unit, and the STC time sensitivity control unit provides a clock signal with high precision and low jitter for the digital signal encoding unit so as to synchronize the output of the digital signal encoding unit;

3. The multi-path V-band signal sampling method according to claim 1 or 2, wherein the low noise amplification module comprises an LM324 amplifier, an OTL amplifier, a variable attenuator, a filter, a power supply, a plurality of capacitors, and a plurality of resistors;

the output end of the filter is connected with the input end of the LM324 amplifier through a coupling capacitor, the output end of the LM324 amplifier is connected with the input end of the variable attenuator through a coupling capacitor, the output end of the variable attenuator is connected with the input end of the OTL amplifier through a coupling capacitor, and the emitters of the OTL amplifier are connected with resistors; the power supply pin is connected with a decoupling capacitor, and a local current path is provided for the LM324 amplifier and the OTL amplifier respectively.

4. The method for sampling a multi-path V-band signal according to claim 3, further comprising:

the filter comprises a frequency divider, an oscillator and at least one tunable filter, the tunable filter is used for suppressing in-band interference signals with the radio frequency band larger than 100GHz in the first signal, and then the frequency of the signals output by the tunable filter is reduced by the frequency divider so as to reduce the frequency of the signals, and the signals are fed back to the oscillator to generate a second signal;

wherein the center frequency of the tunable filter is set to 60GHz; the low-band cut-off frequency was set to 50GHz and the in-band return loss was set to 20dB.

5. The method of claim 4, wherein the mixing module comprises a coupler, a tunable oscillator, a balanced bridge, and a matched load;

the output end of the coupler is connected with the input end of the tunable oscillator through a matching load, and the output end of the tunable oscillator is connected with the balance bridge through a coupling capacitor; selecting an IF channel through a coupler and a tunable oscillator to convert the second signal into an RF frequency band, mixing with a local oscillator signal, inputting the mixing result into a balance bridge, and outputting a third signal;

the balance bridge consists of four Schottky barrier diodes which are connected end to form a ring shape.

6. The method of claim 5, wherein the intermediate frequency module comprises an 8-channel power divider, a square-rate detector, an IF band-pass filter, and an operational amplifier;

the output end of the 8-channel power divider is connected with the input end of the square-rate detector, the input end of the square-rate detector is connected with the input end of the IF band-pass filter, and the output end of the IF band-pass filter is connected with the input end of the operational amplifier; the 8-channel power divider divides the third signal or the signal amplified by the RF amplifier into 8 frequency bands, inputs the 8 frequency bands into the square-rate detector for primary amplification, removes interference signals through the IF band-pass filter, and finally performs secondary amplification through the operational amplifier to output intermediate frequency signals.

7. The multi-path V-band signal sampling method according to claim 6, wherein the signal processing module comprises two FPGA chips and a DSP signal processor;

the two FPGA chips are connected with the DSP signal processor through buses, bit quantization selection, matrix transposition and down-conversion processing of signal channels and frequency channels are carried out on intermediate frequency signals through the FPGA chips, and then filtering processing is carried out through the DSP signal processor, so that V-band digital signals are obtained.

8. A V-band multichannel receiver, comprising:

the A/D converter is configured to perform analog-to-digital conversion on the isolated echo radio frequency signal, output a first signal and send the first signal to the low-noise amplifier module; the A/D converter consists of an analog signal sampling unit, an analog signal quantizing unit, a digital signal encoding unit and an STC time sensitivity control unit, wherein the analog signal sampling unit, the analog signal quantizing unit and the digital signal encoding unit are sequentially connected, the output end of the digital signal encoding unit is connected with the STC time sensitivity control unit, and the STC time sensitivity control unit provides a clock signal with high precision and low jitter for the digital signal encoding unit so as to synchronize the output of the digital signal encoding unit;

the low-noise amplification module is configured to filter noise in the first signal and output a second signal;

the frequency mixing module is configured to perform frequency mixing of the second signal and the local oscillation signal to generate a third signal, wherein if the signal frequency band of the third signal is greater than 50GHz, the third signal is sent to the intermediate frequency module; otherwise, send to the RF amplifier;

an RF amplifier configured to amplify the third signal having a frequency band less than or equal to 50GHz, i.e., to enhance the signal strength of the radio frequency band of the third signal, and then to transmit the amplified signal to the intermediate frequency module; wherein the return loss of the RF amplifier is less than-10 dB;

an intermediate frequency module configured to perform processing of the third signal or the signal pair amplified by the RF amplifier, generating an intermediate frequency signal; the intermediate frequency module comprises an 8-channel power divider, a square-rate detector, an IF band-pass filter and an operational amplifier; the output end of the 8-channel power divider is connected with the input end of the square-rate detector, the input end of the square-rate detector is connected with the input end of the IF band-pass filter, and the output end of the IF band-pass filter is connected with the input end of the operational amplifier; the 8-channel power divider is configured to divide a third signal or a signal amplified by the RF amplifier into 8 frequency bands and input the 8 frequency bands to the square-rate detector for primary amplification, the IF bandpass filter is configured to remove interference signals in the signal output by the square-rate detector, and the operational amplifier is configured to perform secondary amplification on the signal output by the IF bandpass filter and output an intermediate frequency signal;

9. The V-band multichannel receiver of claim 8, wherein said low noise amplification module comprises an LM324 amplifier, an OTL amplifier, a variable attenuator, a filter, a power supply, a plurality of capacitors, and a plurality of resistors;

the output end of the filter is connected with the input end of the LM324 amplifier through a coupling capacitor, the output end of the LM324 amplifier is connected with the input end of the attenuator through a coupling capacitor, the output end of the variable attenuator is connected with the input end of the OTL amplifier through a coupling capacitor, and the emitters of the OTL amplifier are connected with resistors; the power supply pin is connected with a decoupling capacitor, and a local current path is respectively provided for the LM324 amplifier and the OTL amplifier;

10. The V-band multichannel receiver of claim 9, wherein said mixing module comprises a coupler, a tunable oscillator, a balanced bridge, and a matched load;

the output end of the coupler is connected with the input end of the tunable oscillator through a matching load, and the output end of the tunable oscillator is connected with the balance bridge through a coupling capacitor; the coupler and the tunable oscillator are used for selecting an IF channel so as to convert the second signal into an RF frequency band, mix the second signal with a local oscillator signal, input the mixing result into the balance bridge and output a third signal;