Analog frequency measurement circuit
By using an analog frequency measurement circuit and components such as couplers, amplifiers, detectors, and ADCs, the problem of high cost in digital frequency measurement is solved, achieving low-cost, low-power frequency measurement that is suitable for portable devices.
Patent Information
- Application Number
- CN202423112514.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-17
- Publication Date
- 2026-01-02
- Estimated Expiration
- 2034-12-17
AI Technical Summary
Existing frequency measurement methods rely on digital processing technology, which is costly and requires high hardware resources, making it difficult to meet the needs of scenarios with strict limitations on cost, power consumption, and size.
Design an analog frequency measurement circuit, including a coupler, an amplifier, a detector unit, a frequency response network, an ADC, and a microcontroller. The frequency response network composed of capacitors and inductors, combined with the detector and ADC, realizes analog-to-digital conversion, and the microcontroller calculates the frequency.
It achieves low-cost, low-power frequency measurement, is suitable for portable devices, and has high frequency measurement accuracy and frequency testing range.
Smart Images
Figure CN223756815U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to electronic measurement technical field especially, relate to a kind of analog frequency measurement circuit. BACKGROUND
[0002] In the measurement and analysis of radio frequency signal, frequency is an important parameter. The existing frequency measurement method mainly relies on digital processing technology, such as spectrum analyzer or digital frequency meter. Although these methods have high precision, they are relatively high in cost and require high hardware resources. In some scenarios with strict limitations on cost, power consumption and size, traditional digital frequency measurement methods are difficult to meet the needs. UTILITARY MODEL
[0003] The utility model aims at overcoming the shortcomings of prior art, providing an analog frequency measurement circuit, which solves the problems of prior art.
[0004] The utility model discloses a kind of analog frequency measurement circuit, it includes coupler, amplifier, detection unit, frequency response network, ADC and single-chip microcontroller;
[0005] Radio frequency input is connected to the input end of coupler, the output end of coupler is connected to the input end of amplifier, and the amplified signal power after coupling is input to the detection unit after being amplified to the power size required for detection by the amplifier; the detection unit is connected to the frequency response network to detect the power difference between the front and rear ends of the frequency response network and input to the ADC, and the ADC converts the power difference signal into digital signal and inputs to the single-chip microcontroller.
[0006] The detection unit includes a first detector and a second detector, the output end of the amplifier is connected to the input end of the first detector, and the output end of the first detector is connected to the input end of the frequency response network and the ADC respectively; the output end of the frequency response network is connected to the input end of the second detector, and the output end of the second detector is connected to the input end of the ADC.
[0007] The frequency response network is composed of a capacitor and an inductor, the output end of the first detector is connected to the capacitor, and the input end of the second detector is connected to the inductor.
[0008] The output end of the second detector is also connected to a load to prevent signal emission.
[0009] The utility model has the following advantages: an analog frequency measurement circuit, low in cost, suitable for power-sensitive scenarios, and suitable for portable devices; by optimizing circuit design, high frequency measurement accuracy and high frequency test range can be achieved. BRIEF DESCRIPTION OF DRAWINGS
[0010] Figure 1 It is the circuit structure schematic diagram of the utility model. DETAILED DESCRIPTION
[0011] To make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application and are not all the embodiments. The components of the embodiments of the present application described and shown in the accompanying drawings can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in conjunction with the accompanying drawings is not intended to limit the protection scope of the claimed present application, but only represents selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the present application. The present application will be further described below with reference to the accompanying drawings.
[0012] As shown in the accompanying drawings, the present application specifically relates to a simulation frequency measurement circuit, which realizes the measurement of the frequency of a radio frequency signal by utilizing the frequency response characteristics of capacitors or inductors to different frequency signals, combining a detector and an ADC (analog-to-digital converter). Figure 1 The method has the characteristics of low cost, low power consumption and small size, is suitable for the frequency measurement of radio frequency signals, and is particularly suitable for scenarios with strict requirements on cost, power consumption and size, such as wireless communication devices and portable test instruments.
[0013] It comprises a coupler, an amplifier, a detector, a frequency response network, an ADC, a single-chip microcomputer and a load; wherein the coupler couples the radio frequency signal into the frequency response network, the amplifier amplifies the power of the coupled signal to the power size required for detection, the frequency response network is composed of capacitors and inductors and is used to generate frequency-dependent insertion loss for the input radio frequency signal, the detector is used to detect the power difference between the front and rear ends of the frequency response network, the ADC is used to convert the power difference signal output by the detector into a digital signal, the single-chip microcomputer is used to process and calculate the digital signal, and finally the frequency of the input signal is obtained, and the load is used to consume the remaining power to prevent signal reflection from affecting the test results.
[0014] Further, according to the different frequency bands to be measured, a response network in the form of one or more levels of Π type or T type (the specific values need to be obtained by simulation) is composed of capacitors and inductors. The purpose is to increase the frequency response slope of the radio frequency signals in the frequency band to be measured and increase the linearity of the attenuation in this frequency band, so as to increase the test precision.
[0015] Further, by reasonably designing the parameters of the capacitors or inductors, a higher insertion loss slope can be obtained, thereby improving the frequency measurement precision, a detector with a larger dynamic range and higher resolution is preferably selected to expand the frequency measurement range and improve the frequency measurement resolution, and an ADC with a higher bit number is preferably selected to improve the frequency measurement resolution.
[0016] Further, the single-chip computer calculates the frequency of the input signal according to the insertion loss characteristic of the frequency response network and the power difference, and the calculation formula is as follows:
[0017] f=F(Pin-Pout)
[0018] Wherein, f is the frequency of the input signal, Pin and Pout are the power of the front and rear end of the frequency response network respectively, and F is the function of the insertion loss slope.
[0019] The working process of the utility model is as follows: the radio frequency signal is input to the frequency response network through the coupler and the amplifier, the insertion loss of the frequency response network changes with the change of the input signal frequency, the power of the front and rear end of the frequency response network is detected by the detector respectively, and the power difference signal is output, the power difference signal output by the detector is converted into digital signal by the ADC, and the frequency of the input signal is calculated by the single-chip computer according to the power difference and the insertion loss slope of the frequency response network.
[0020] The above is only the preferred embodiment of the utility model, and it should be understood that the utility model is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used for various other combinations, modifications and improvements, and can be changed within the scope of the concept described herein by the above teaching or related technical or knowledge. The change and variation made by the person in the art without departing from the spirit and scope of the utility model should be within the protection scope of the claims attached to the utility model.
Claims
1. An analog frequency measuring circuit, characterized by: It includes a coupler, an amplifier, a detection unit, a frequency response network, an ADC and a single-chip microcomputer; The radio frequency input is connected to the input end of the coupler, the output end of the coupler is connected to the input end of the amplifier, the amplifier amplifies the coupled signal power to the required power size and inputs it to the detection unit, the detection unit is connected to the frequency response network to detect the power difference between the front and rear ends of the frequency response network and inputs it to the ADC, and the ADC converts the power difference signal into a digital signal and inputs it to the single-chip microcomputer.
2. An analog frequency measuring circuit according to claim 1, characterized in that The detection unit includes a first detector and a second detector, the output end of the amplifier is connected to the input end of the first detector, the output end of the first detector is connected to the input end of the frequency response network and the ADC respectively, the output end of the frequency response network is connected to the input end of the second detector, and the output end of the second detector is connected to the input end of the ADC.
3. An analog frequency measuring circuit according to claim 2, characterized in that: The frequency response network is composed of a capacitor and an inductor, the output end of the first detector is connected to the capacitor, and the input end of the second detector is connected to the inductor.
4. An analog frequency measuring circuit according to claim 2, characterized in that: The output end of the second detector is also connected to a load to prevent signal emission.