CN210327547U

CN210327547U - Real-time frequency spectrum monitoring equipment

Info

Publication number: CN210327547U
Application number: CN201921910594.4U
Authority: CN
Inventors: 沙文祥; 张明珠
Original assignee: Nanjing Glarun Atten Technoogy Co ltd
Current assignee: Nanjing Glarun Atten Technoogy Co ltd
Priority date: 2019-11-07
Filing date: 2019-11-07
Publication date: 2020-04-14
Anticipated expiration: 2029-11-07

Abstract

The utility model discloses a real-time frequency spectrum monitoring facilities, including receiving channel module, frequency synthesis module, digital circuit module, the frequency synthesis module is connected with the receiving channel module, the receiving channel module is used for receiving various radio-frequency signal and local oscillator signal mixing, the receiving channel module is connected with the digital circuit module, the receiving channel module is used for carrying out signal analysis with signal processing back input digital circuit module. The utility model discloses real-time test, temperature range are wide, measurement accuracy is high, the phase noise is low, the modularized design, the spectrum monitoring facilities that the reliability is high.

Description

Real-time frequency spectrum monitoring equipment

Technical Field

The utility model relates to a radar, communication, spectrum monitoring technology field, especially a real-time spectrum monitoring facilities.

Background

With the development of communication technology, radar, electronic countermeasure and related technologies, higher and more comprehensive demands are made on spectrum monitoring equipment. The monitoring equipment is required to have higher measurement precision, more accurate frequency resolution, wider power range, better phase noise and richer functions. At present, special radio frequency spectrum monitoring equipment which is good in instantaneity, low in power consumption, small in size, modularized and functional is not released temporarily.

Disclosure of Invention

To the problem that exists among the prior art, the utility model provides a frequency spectrum monitoring facilities that real-time test, temperature range are wide, measurement accuracy is high, the phase noise is low, the modularized design, the reliability is high.

The purpose of the utility model is realized through the following technical scheme.

A real-time frequency spectrum monitoring device comprises a receiving channel module, a frequency synthesis module and a digital circuit module, wherein the frequency synthesis module is connected with the receiving channel module, the receiving channel module is used for receiving various radio-frequency signals and local oscillator signal mixing, the receiving channel module is connected with the digital circuit module, and the receiving channel module is used for inputting the processed signals into the digital circuit module for signal analysis.

The receiving channel module performs frequency preselection, frequency conversion and amplification on the received radio frequency signal and provides an intermediate frequency signal;

the frequency synthesis module provides local oscillation signals required by frequency conversion;

the digital circuit module receives the intermediate frequency signal and processes the frequency, phase noise, power and stray indexes of the signal in real time through the FPGA.

The receiving channel module comprises a front-end circuit and a low-waveband channel, wherein the front-end circuit is used for sorting input radio-frequency signals into different channels, and the low-waveband channel is used for converting the sorted radio-frequency signals into intermediate-frequency signals through frequency conversion and outputting the intermediate-frequency signals by utilizing the superheterodyne principle.

The front-end circuit comprises a high-speed switch and filters with different wave bands, and an attenuator, a low-pass filter, a first mixer, a first amplifier, a band-pass filter, a second mixer and a second amplifier are sequentially arranged on a low-wave band channel.

Compared with the prior art, the utility model has the advantages of: the utility model discloses through high-speed cable between each module, fiber cable carries out reliably, stable communication is connected, it is high through shielding nature, the standing wave is good, insert the transmission that the little semi-flexible cable of loss carries out radio frequency signal, through the various spurs of receiving channel module preselection signal filtering, produce high phase noise through the frequency synthesis module, low spurious local oscillator signal, FPGA processing information through the high-speed high performance of digital circuit module, thereby realized index measurement accuracy such as phase noise, power, frequency, spurs is good, the high real-time supervision of measuring accuracy. To sum up, the utility model discloses real-time test, temperature range are wide, measurement accuracy is high, the phase noise is low, the modularized design, and the reliability is high.

Drawings

Fig. 1 is a schematic block diagram of a novel real-time spectrum monitoring device.

Fig. 2 is a block diagram of a receiving channel of the novel real-time spectrum monitoring device.

Fig. 3 is a schematic block diagram of a front-end circuit of the novel real-time spectrum monitoring device.

Fig. 4 is a schematic block diagram of a low channel band of the novel real-time spectrum monitoring device.

Fig. 5 is a schematic block diagram of frequency synthesis of the novel real-time spectrum monitoring device.

Fig. 6 is a schematic block diagram of a digital circuit of the novel real-time spectrum monitoring device.

Detailed Description

The invention is described in detail below with reference to the drawings and specific examples.

As shown in fig. 1, this is a schematic diagram of the overall operation principle of the real-time spectrum monitoring device. The real-time frequency spectrum monitoring equipment is composed of a receiving channel module, a frequency synthesis module and a digital circuit module respectively, and receives a signal command through an optical fiber and transmits a monitoring measurement result through the optical fiber. The receiving channel module receives various radio frequency signals and local oscillation signals generated by the frequency synthesis module for frequency mixing, and the signals are processed and then input into the digital circuit module for signal analysis, so that the indexes of frequency, phase noise, power, stray and the like of a signal frequency spectrum are processed in real time. The receiving channel module performs frequency preselection, frequency conversion and amplification on the received radio frequency signal. Providing a high-performance and high-quality intermediate frequency signal; the frequency synthesis module provides local oscillation signals with high phase noise and low stray indexes required by frequency conversion; the digital circuit module receives the intermediate frequency signal, and the high-speed and high-performance FPGA is used for processing indexes such as frequency, phase noise, power, stray and the like of the signal in real time. The specific implementation of the real-time spectrum monitoring device is as follows: the signal receiving process is divided into two parts, one part is that a control command and a synchronous signal are received through an optical fiber interface and sent to a digital circuit module for processing, and a receiving channel module and a frequency synthesis module are controlled after the command is converted; the other part is that the monitored radio frequency signal is received through a radio frequency interface, the monitored radio frequency signal firstly passes through a receiving channel module, frequency preselection is carried out in the receiving channel module through a front end circuit, then frequency mixing is carried out in a low channel wave band with a local oscillation signal generated by a frequency synthesis module, and an intermediate frequency signal after frequency mixing enters a digital circuit module to carry out signal analysis, extraction, judgment and result obtaining.

As shown in fig. 2, the receiving channel module mainly includes a front-end circuit and a low-band channel. The front-end circuit is responsible for sorting input radio frequency signals into different channels, and the low-waveband channel is responsible for converting the sorted radio frequency signals into intermediate frequency signals through frequency conversion and outputting the intermediate frequency signals by utilizing the superheterodyne principle.

As shown in fig. 3, the front-end circuit is mainly composed of a high-speed switch and various filters of different bands. The front-end circuit determines standing wave ratio of input signals, input frequency preselection, and indexes such as frequency response time and noise coefficient which are mainly influenced. Therefore, a circuit with low insertion loss, low standing wave, fast response time and good channel filtering is designed. Meanwhile, reverse signal isolation is considered, and the filter is added to filter signals generated by the module, so that the signals are prevented from being reversely connected back to the tested equipment to influence the tested equipment.

As shown in fig. 4, the low-band channel first mixes the radio frequency signal with the first local oscillator signal to obtain a first intermediate frequency, and the first intermediate frequency is amplified and filtered to filter out various clutter of the mixed signal and sent to the second mixer. And then the second intermediate frequency signal is obtained by mixing with a second local oscillation signal, and then the second intermediate frequency signal is output to a digital circuit module for digital signal processing after passing through a band-pass filter and a variable gain amplifier to filter stray and amplify the signal.

As shown in fig. 5, the frequency synthesis module mainly generates a local oscillation signal. The frequency source is divided into 2 independent frequency sources, and each frequency source is obtained by a high-performance phase-locked loop. The frequency sweep bandwidth is ensured by the phase-locked loop, the high-phase noise index of the whole frequency synthesis module is ensured by nested frequency mixing of a plurality of phase-locked loops, the stray suppression index of the frequency synthesis module is ensured by proper loop filtering, the power requirement of the output local oscillator is ensured by the amplifier, and finally the local oscillator frequency is output.

As shown in fig. 6, after the rf signal is processed by the receiving channel module, the differential signal output by the intermediate frequency directly enters the ADC of the digital circuit module; the ADC samples with a 400MHz clock, and provides sampling data and a synchronous clock to the FPGA; the FPGA mainly completes the realization of Digital Down Conversion (DDC), FFT, control logic and interface protocol; and the DSP assists the FPGA to complete related intermediate frequency processing and control.

This kind of novel real-time spectrum monitoring equipment is through high-speed cable between each module, fiber optic cable carries out reliably, stable communication is connected, it is high through shielding nature, the standing wave is good, the little semi-flexible cable of insertion loss carries out the transmission of radio frequency signal, through the various strays of receiving channel module pre-selected signal filtering, produce high phase noise through the frequency synthesis module, low spurious local oscillator signal, through the high-speed high performance's of digital circuit module FPGA processing information, thereby realized to phase noise, power, frequency, index measurement accuracy such as strays is good, the high real-time supervision of measurement accuracy.

The novel real-time spectrum monitoring device is mainly used for monitoring the spectrum of a radio frequency signal in real time, realizes the collection and analysis of important data in the monitoring process, has the function of auxiliary fault diagnosis, and provides an important means for the monitoring, the detection and the maintenance of equipment such as radars, communication and the like.

Claims

1. A real-time frequency spectrum monitoring device comprises a receiving channel module, a frequency synthesis module and a digital circuit module, and is characterized in that the frequency synthesis module is connected with the receiving channel module, the receiving channel module is used for receiving various radio frequency signals and local oscillator signal mixing, the receiving channel module is connected with the digital circuit module, and the receiving channel module is used for processing the signals and inputting the processed signals into the digital circuit module.

2. The apparatus according to claim 1, wherein the receiving channel module performs frequency preselection, frequency conversion, amplification on the received rf signal, and provides an if signal;

3. The apparatus according to claim 1 or 2, wherein the receiving channel module comprises a front-end circuit and a low-band channel, the front-end circuit is configured to sort the input rf signals into different channels, and the low-band channel is configured to convert the sorted rf signals into the if signals by frequency conversion using superheterodyne principle.

4. The apparatus according to claim 3, wherein said front-end circuit comprises a high-speed switch and filters of different bands, and said low band channel is provided with an attenuator, a low-pass filter, a first mixer, a first amplifier, a band-pass filter, a second mixer, and a second amplifier in sequence.