Pass-type spectrum analysis device

Abstract

The utility model provides a pass-type spectrum analysis device, which comprises a spectrum analysis module and a coupling module, and the coupling module can directly pass through a high-power or super-power radio frequency signal and couple a small part to the spectrum analysis module. The frequency spectrum analysis module carries out amplification and frequency division sampling operation on the small part of radio frequency signals and then inputs the signals to the signal sampling analysis unit, the signal sampling analysis unit converts analog signals into frequency domain information, and the frequency spectrum analysis of the large-power radio frequency signal part frequency band is achieved by correcting the coupling degree. The frequency division sampling operation is repeated, so that the frequency spectrum information of other different frequency bands in the high-power radio frequency signal can be continuously obtained, and the complete test of the frequency spectrum characteristic of the high-power radio frequency signal is realized. In addition, the pass-type spectrum analysis device further integrates a display part, a power supply part and a communication part, and is simple in structure, small in size, high in integration level and suitable for outfield testing.

Description

Technical Field

[0001] The utility model belongs to the technical field of radio spectrum signal management, and in particular relates to a through-type spectrum analysis device. Background Art

[0002] A spectrum analyzer is an instrument for studying the spectrum characteristics of high-frequency electrical signals. It is used to measure signal parameters such as signal distortion, modulation, spectrum purity, frequency stability and intermodulation distortion. It is a multi-purpose general electronic measuring instrument.

[0003] Currently, spectrum analyzers on the market are all single-port absorption devices. The energy of the connected measured signal is eventually absorbed by the spectrum analyzer, and the maximum input power allowed is generally only 1W. Some high-power spectrum analyzers can analyze larger high-power signals because they have integrated attenuators, but the weight and volume will also increase a lot, and the greater the power, the greater the weight and volume, even up to 100kg, which is very inconvenient to carry. With the development of radio frequency microwave technology, the radio frequency energy (power) used in the fields of communication, radar and semiconductor processing is getting larger and larger, usually reaching the kilowatt level. In order to conveniently and quickly measure the spectrum characteristics of high-power radio frequency, especially in the field background, such as field communication base stations, a small and portable instrument that can directly measure the spectrum characteristics of high-power radio frequency signals is essential. Utility Model Content

[0004] The utility model provides a through-type spectrum analysis device, which can directly access and measure high-power radio frequency signals or microwave signals and analyze the spectrum characteristics thereof.

[0005] The utility model provides a through-type spectrum analysis device, comprising: a spectrum analysis module and a coupling module;

[0006] The spectrum analysis module includes: a first signal processing unit, a switch wave selection unit and a signal sampling and analysis unit;

[0007] The coupling module couples part of the radio frequency signal to the first signal processing unit within the analysis frequency band, and the first signal processing unit processes the radio frequency signal and then inputs the radio frequency signal to the switch wave selection unit;

[0008] After the switch wave selection unit divides the radio frequency signal into different frequency bands, the frequency division signals of different frequency bands are switched to the signal sampling and analysis unit, and the signal sampling and analysis unit performs spectrum analysis on the frequency division signals.

[0009] Further, the coupling unit includes a coupling cavity;

[0010] The coupling cavity is used to guide the radio frequency signals within the analysis frequency band to pass through, and couple out part of the radio frequency signals within the analysis frequency band.

[0011] Further, the first signal processing unit includes a low noise amplifier;

[0012] The low noise amplifier is used to amplify the radio frequency signal and input the radio frequency signal to the switch wave selection unit.

[0013] Furthermore, the signal sampling and analysis unit includes a filter group and a switching switch; the filter group is used to divide the radio frequency signal into multiple frequency bands; and the switching switch is used to control the filter group to output frequency-divided signals of different frequency bands.

[0014] Furthermore, the spectrum analysis module also includes a frequency conversion unit, and the frequency conversion unit is used to perform frequency conversion processing on the frequency-divided signal.

[0015] Furthermore, the frequency conversion unit includes: a mixer and a local oscillator signal source;

[0016] The local oscillator signal source is used to provide a local oscillator signal;

[0017] The mixer is used to mix the local oscillator signal with the frequency-divided signal, and down-convert the frequency-divided signal into an intermediate frequency signal.

[0018] Furthermore, the spectrum analysis module also includes a second signal processing unit, and the second signal processing unit is used to perform signal amplification and filtering processing on the intermediate frequency signal.

[0019] Furthermore, the second signal processing unit includes: an intermediate frequency amplifier and an intermediate frequency filter;

[0020] The intermediate frequency amplifier is used to amplify the intermediate frequency signal;

[0021] The intermediate frequency filter is used to filter out clutter in the intermediate frequency signal.

[0022] Furthermore, the signal sampling and analysis unit includes an ADC acquisition unit; the ADC acquisition unit is used to convert the intermediate frequency signal into a digital signal.

[0023] Furthermore, the signal sampling and analysis unit also includes an FPGA data processing unit;

[0024] The FPGA data processing unit is used to control the switch wave selection unit to output frequency-divided signals of different frequency bands to the frequency conversion unit, and control the frequency conversion unit to perform frequency conversion processing on the frequency-divided signals;

[0025] The FPGA data processing unit is also used to convert the digital signal output by the ADC acquisition unit into frequency domain information.

[0026] Compared with the prior art, the utility model has at least the following technical effects:

[0027] The through-type spectrum analysis device provided by the utility model includes a spectrum analysis module and a coupling module. The coupling module can directly pass the high-power RF signal and couple a small part of the RF signal to the spectrum analysis module. The spectrum analysis module amplifies and performs frequency division sampling operations on this small part of the RF signal and then inputs it into the signal sampling and analysis unit. The signal sampling and analysis unit converts the analog signal into frequency domain information to realize the analysis of some frequency bands of the high-power RF signal. By repeating the frequency division sampling operation, the information of the remaining different frequency bands in the high-power RF signal can be continuously obtained, and the complete test of the high-power RF signal including the spectrum characteristics and power information can be realized. The above-mentioned through-type spectrum analysis device has a simple structure and is suitable for field testing. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of the structure of each module in a through-type spectrum analysis device in an embodiment;

[0029] Figure 2 A spectrum diagram measured and displayed by a through-type spectrum analyzer when a high-power signal passes through in an embodiment;

[0030] Figure 3 FIG. 1 is a signal spectrum diagram displayed on a spectrum analyzer when a high-power signal passes through in an embodiment. DETAILED DESCRIPTION

[0031] A through-type spectrum analysis device of the present invention will be described below in conjunction with a schematic diagram, wherein a preferred embodiment of the present invention is shown. It should be understood that those skilled in the art can modify the present invention described herein and still achieve the beneficial effects of the present invention. Therefore, the following description should be understood as being widely known to those skilled in the art and not as a limitation to the present invention.

[0032] The present invention is described in more detail in the following paragraphs by way of example with reference to the accompanying drawings. The advantages and features of the present invention will become more apparent from the following description. It should be noted that the accompanying drawings are in very simplified form and in non-precise proportions, and are only used to facilitate and clearly illustrate the embodiments of the present invention.

[0033] Please refer to Figure 1 This embodiment provides a through-type spectrum analysis device, including a spectrum analysis module 1 and a coupling module 2.

[0034] The coupling module 2 is used to couple a small portion of the radio frequency signal from the passing high-power radio frequency signal to the spectrum analysis module 1, and the spectrum analysis module 1 is used to perform signal processing and signal analysis on the coupled radio frequency signal.

[0035] Specifically, the spectrum analysis module 1 includes: a first signal processing unit, a switch selection unit and a signal sampling and analysis unit; the coupling module 2 couples part of the RF signal to the signal amplification unit within the analysis frequency band, and the first signal processing unit performs signal processing on the RF signal and then inputs the RF signal to the switch selection unit; the switch selection unit divides the RF signal into different frequency bands and then switches the divided frequency signals of different frequency bands to the signal sampling and analysis unit, and the signal sampling and analysis unit performs spectrum analysis on the divided frequency signal.

[0036] The coupling module 2 provided in the above-mentioned through-type spectrum analysis device can directly pass high-power radio frequency signals, such as 10 kW and 30 kW radio frequency signals, and couple a small part to the spectrum analysis module 1. The spectrum analysis module 1 amplifies and samples the small part of the radio frequency signal in turn, and then inputs it into the signal sampling and analysis unit to convert it into frequency domain information. The through-type spectrum analysis device can measure the signal characteristics of high-power radio frequency signals exceeding 1 watt in sections, and has a simple structure, which is suitable for field testing.

[0037] In a specific embodiment, the spectrum analysis module 1 and the coupling module 2 are integrated into one body to form a miniaturized spectrum analysis device, which is convenient for off-site carrying.

[0038] In another specific embodiment, the spectrum analysis module 1 can measure high-power radio frequency signals exceeding 1 kilowatt, and can also measure low-power and micro-power radio frequency signals, such as radio frequency signals of -40dBm to +10dBm.

[0039] In another specific embodiment, the spectrum analysis module 1 can measure, including but not limited to, signal frequency, signal amplitude, signal power, signal distortion, modulation, spectrum purity and frequency stability.

[0040] In another specific embodiment, the coupling unit includes a coupling cavity, and the cavity has a special electromagnetic field distribution inside, which can smoothly guide the RF signal in the analysis frequency band to pass through, and couple out part of the RF signal in the analysis frequency band. The coupling method is not specifically limited here, for example, a specific port or antenna is set at the edge of the coupling cavity to extract this part of the weak RF signal.

[0041] In another specific embodiment, the first signal processing unit includes a low noise amplifier; the low noise amplifier is used to amplify the small radio frequency signal extracted by the coupling cavity, and input the radio frequency signal to the switch wave selection unit.

[0042] In another specific embodiment, the signal sampling and analysis unit includes a filter group and a switching switch; the filter group is used to divide the radio frequency signal into multiple frequency bands; the switching switch is used to control the filter group to output frequency-divided signals of different frequency bands. The number and type of filters are not specifically limited here. For example, the filter group is designed to include N bandpass filters, N low-pass filters and / or N high-pass filters, and the number and type of switches are not specifically limited here. For example, N analog switches, N digital switches and / or N radio frequency switches are set.

[0043] In a specific example, for example, when a spectrum analysis is to be performed on a radio frequency signal in the frequency range of 4kHz to 40GHz, N bandpass filters with different center frequencies can be set in the filter group to divide the entire frequency band to be analyzed into N frequency bands, for example: the first frequency band: 4kHz-2MHz; the second frequency band: 2MHz-10MHz; the Nth frequency band: 30GHz-40GHz, each bandpass filter covers a frequency band; the N switching switches are controlled by N control signals, each control signal corresponds to a filter, and is used to control the opening and closing of the filter. Assuming that the signal of the second frequency band of 2MHz-10MHz needs to be analyzed, the control signal controls any switching switch to turn on the third filter and turn off other filters, and the frequency division signal is input into the frequency conversion unit.

[0044] Furthermore, the through-type spectrum analysis device provided in this embodiment also includes a frequency conversion unit, which is used to perform frequency conversion processing on the divided frequency signal. The purpose of frequency conversion is to convert the high-frequency RF signal into an intermediate frequency signal suitable for the sampling rate of the sampling analysis unit, so as to achieve effective analysis of the RF signal.

[0045] In a specific embodiment, the frequency conversion unit includes: a mixer and a local oscillator signal source. The local oscillator signal source is used to provide a stable local oscillator signal, such as a high-frequency sine wave signal; the mixer is used to mix the local oscillator signal with the frequency division signal, thereby down-converting the frequency division signal into an intermediate frequency signal. During the mixing process, the local oscillator signal and the radio frequency signal are phase-multiplied to generate a composite signal of two frequencies, one frequency is the sum of the local oscillator signal and the radio frequency signal frequency, and the other is their difference. Through the selective filtering of the mixer circuit, the required difference frequency signal can be extracted to achieve frequency conversion.

[0046] Furthermore, the through-type spectrum analysis device provided in this embodiment also includes a second signal processing unit, which is used to amplify and filter the intermediate frequency signal. The purpose of signal amplification and filtering is to remove noise or other signal interference that may be contained in the intermediate frequency signal, adjust the stability of the intermediate frequency signal, and provide a higher quality input signal for subsequent digital signal processing.

[0047] In a specific embodiment, the second signal processing unit includes an intermediate frequency amplifier and an intermediate frequency filter; the intermediate frequency amplifier is used to amplify the intermediate frequency signal; the intermediate frequency filter is used to filter out clutter in the intermediate frequency signal and suppress out-of-band noise and interference.

[0048] Preferably, the second processing unit may also include an automatic gain control circuit, an intermediate frequency attenuator, a radio frequency suppression filter and a phase equalizer; the automatic gain control circuit is used to make the amplified intermediate frequency signal within a suitable amplitude range to avoid signal distortion; the intermediate frequency attenuator is used to automatically adjust the amplitude of the intermediate frequency signal to adapt to different signal input amplitude ranges; the radio frequency suppression filter is used to suppress radio frequency leakage that may be generated by the intermediate frequency amplifier to avoid interference with the radio frequency circuit; the phase equalizer is used to correct the phase distortion of the intermediate frequency signal and improve the linearity of the frequency response. The above design can improve the stability of the second processing unit, enable it to better adapt to the amplitude and frequency characteristics of different signals, and provide a high-quality signal source for subsequent signal processing.

[0049] In another specific embodiment, the signal sampling and analysis unit includes an ADC (Analog-to-Digital Converter) acquisition unit; the ADC acquisition unit converts the intermediate frequency signal into a digital signal, and realizes spectrum analysis of a partial frequency band of the high-power RF signal by correcting the coupling degree.

[0050] In another specific embodiment, the signal sampling and analysis unit also includes an FPGA data processing unit (Field-Programmable Gate Array), which can control the switch selection unit to switch and select different frequency bands in the frequency band from the starting point to the end point of the frequency band, and output the allocation signal of any frequency band to the frequency conversion unit; the FPGA data processing unit can also control the frequency conversion unit to perform frequency conversion processing on the divided frequency signal. After the divided frequency signal after frequency conversion processing is input into the second signal processing unit and the ADC sampling unit in turn, the FPGA data processing unit collects the discrete digital signal provided by the ADC sampling unit, and converts the digital signal into a series of frequency domain information composed of sine or cosine functions through the Fourier transform algorithm, thereby realizing the spectrum analysis of the divided frequency signal.

[0051] Using the specific structures of the spectrum analysis module 1 and the coupling module 2 provided in the above embodiment, the specific working process of the spectrum analysis device is as follows:

[0052] A high-power signal is input to the coupling module 2, and the coupling module 2 realizes the coupling output of a part of the RF signal. The coupled output RF signal is amplified by the first signal processing unit to obtain sufficient power; the first signal processing unit inputs the RF signal to the switch selection unit, and the FPGA data processing unit controls the switch selection unit to switch and select different frequency bands in the frequency band of the RF signal from the starting point to the end point of the frequency band, and outputs the divided frequency signal of any frequency band to the frequency conversion unit; the frequency conversion unit down-converts the divided frequency signal into an intermediate frequency signal for ADC sampling; the intermediate frequency signal is input to the second signal processing unit, and the second signal processing unit amplifies and filters the intermediate frequency signal and then inputs it to the ADC acquisition unit. The ADC acquisition unit converts the analog signal into a digital signal and then inputs the digital signal into the FPGA data processing unit. The FPGA data processing unit converts the digital signal into frequency domain information to obtain the spectrum information of some frequency bands in the entire frequency band signal. Among them, the FPGA controls the switch selection unit to select different frequency bands in turn, the frequency conversion unit down-converts the frequency, the second signal processing unit processes the signal, the ADC samples, and finally the FPGA processes and displays the spectrum. This process is repeated until the entire frequency band is covered, thereby realizing the analysis of the entire frequency band signal.

[0053] It can be understood that the specific units provided in the spectrum analysis module 1 provided in this embodiment can be selected according to actual conditions, including but not limited to the above specific embodiments.

[0054] Preferably, the pass-through spectrum analysis device further comprises an electronic touch screen display. The FPGA data processing unit can control the electronic touch screen display to display the spectrum information.

[0055] Preferably, the pass-through spectrum analysis device further includes a power supply interface and a remote communication interface, wherein the power supply interface is used to supply power to the pass-through spectrum analysis device, and the remote communication interface is used to implement remote control and data transmission of the device.

[0056] Please refer to Figure 2 , Figure 2 The figure shows the spectrum diagram measured and displayed by the spectrum analyzer in this embodiment when a high-power signal passes through. Please refer to Figure 3 , Figure 3As shown in the figure, when the same RF signal is connected in this embodiment, after the RF signal output end of the pass-through spectrum analyzer is connected to the attenuator and the spectrum analyzer in sequence, the signal spectrum diagram displayed on the spectrum analyzer. It can be seen that the signal power value and spectrum diagram displayed in the pass-through spectrum analyzer are almost the same as the signal power value and spectrum diagram displayed on the spectrum analyzer, which confirms that the pass-through spectrum analyzer provided in this embodiment can directly analyze high-power signals.

[0057] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A through-type spectrum analysis device, characterized in that: include: Spectrum analysis module and coupling module; The spectrum analysis module includes: a first signal processing unit, a switch wave selection unit and a signal sampling and analysis unit; The coupling module couples part of the radio frequency signal to the first signal processing unit within the analysis frequency band, and the first signal processing unit processes the radio frequency signal and then inputs the radio frequency signal to the switch wave selection unit; After the switch wave selection unit divides the radio frequency signal into different frequency bands, the frequency division signals of different frequency bands are switched to the signal sampling and analysis unit, and the signal sampling and analysis unit analyzes the frequency division signals.

2. The through-type spectrum analysis device according to claim 1, characterized in that: The coupling module includes a coupling cavity; The coupling cavity is used to guide the radio frequency signals within the analysis frequency band to pass through, and couple out part of the radio frequency signals within the analysis frequency band.

3. The through-type spectrum analysis device according to claim 1, characterized in that: The first signal processing unit includes a low noise amplifier; The low noise amplifier is used to amplify the radio frequency signal and input the radio frequency signal to the switch wave selection unit.

4. The through-type spectrum analysis device according to claim 1, characterized in that: The signal sampling and analysis unit includes a filter bank and a switch; The filter bank is used to divide the radio frequency signal into multiple frequency bands; The switch is used to control the filter group to output frequency division signals of different frequency bands.

5. The through-type spectrum analysis device according to claim 1, characterized in that: The spectrum analysis module further includes a frequency conversion unit, and the frequency conversion unit is used to perform frequency conversion processing on the frequency-divided signal.

6. The through-type spectrum analysis device according to claim 5, characterized in that: The frequency conversion unit includes: a mixer and a local oscillator signal source; The local oscillator signal source is used to provide a local oscillator signal; The mixer is used to mix the local oscillator signal with the frequency-divided signal, and down-convert the frequency-divided signal into an intermediate frequency signal.

7. The through-type spectrum analysis device according to claim 6, characterized in that: The spectrum analysis module further includes a second signal processing unit, which is used to perform signal amplification and filtering processing on the intermediate frequency signal.

8. The through-type spectrum analysis device according to claim 7, characterized in that: The second signal processing unit includes: an intermediate frequency amplifier and an intermediate frequency filter; The intermediate frequency amplifier is used to amplify the intermediate frequency signal; The intermediate frequency filter is used to filter out clutter in the intermediate frequency signal.

9. The through-type spectrum analysis device according to claim 8, characterized in that: The signal sampling and analysis unit includes an ADC acquisition unit; The ADC acquisition unit is used to convert the intermediate frequency signal into a digital signal.

10. The through-type spectrum analysis device according to claim 9, characterized in that: The signal sampling and analysis unit also includes an FPGA data processing unit; The FPGA data processing unit is used to control the switch wave selection unit to output frequency-divided signals of different frequency bands to the frequency conversion unit, and control the frequency conversion unit to perform frequency conversion processing on the frequency-divided signals; The FPGA data processing unit is also used to convert the digital signal output by the ADC acquisition unit into frequency domain information.

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