Digital power meter of broadcast transmitter

Abstract

The broadcast transmitter digital power meter comprises a signal filtering and amplifying circuit, a signal processing module electrically connected with the signal filtering and amplifying circuit, and a signal output module electrically connected with the signal processing module, the signal filtering and amplifying circuit comprises an LM324N operational amplifier and filtering capacitors C1-C8; the signal processing module comprises a single-chip microcomputer which comprises an AD conversion circuit, a digital filtering module, a power calibration module and a DA conversion circuit. The signal output module comprises a display screen and an analog output interface. High-frequency harmonic suppression is realized through multi-stage capacitor filtering, high-precision amplification is realized, high-quality digitalization of a transmitter power meter is realized, and the problems of low precision and poor interference resistance of a traditional analog meter head are solved.

Description

Technical Field

[0001] This utility model relates to the field of broadcast transmitter technology, and in particular to a digital power meter for broadcast transmitters. Background Technology

[0002] In broadcast transmitter systems, power meters serve as crucial monitoring devices, playing a key role in reflecting the transmitter's operational status in real time. Power meters are divided into two categories: incident power meters and reflected power meters. They display power values ​​through analog pointers, and their operating principle relies on a mechanical response. Currently, this type of analog power meter is widely used in my country's broadcast transmitter industry. However, the analog meter head is limited by its mechanical structure, resulting in significant reading errors and slow response speeds. Moreover, finished products are entirely dependent on imports, leading to high procurement costs. Utility Model Content

[0003] This invention provides a digital power meter for broadcast transmitters, which solves the problems of large reading errors and slow response speed of mechanical analog meters in related technologies.

[0004] To achieve the above objectives, this application adopts the following technical solution:

[0005] In a first aspect, a digital power meter for a broadcast transmitter is provided, comprising:

[0006] A signal filtering and amplification circuit, a signal processing module electrically connected to the signal filtering and amplification circuit, and a signal output module electrically connected to the signal processing module;

[0007] The signal filtering and amplification circuit includes: an LM324N operational amplifier and filter capacitors C1-C8; the LM324N operational amplifier includes operational amplifiers A1, A2, A3 and A4, operational amplifiers A1 and A2 are connected in the form of non-inverting amplifiers to form an input buffer and are connected in parallel to the input terminal of operational amplifier A3, and the output terminal of operational amplifier A3 is connected to the input terminal of operational amplifier A4;

[0008] The signal input terminal of operational amplifier A1 is connected to one end of filter capacitor C1, and the other end of filter capacitor C1 is grounded. The signal input terminal of operational amplifier A2 is connected to one end of filter capacitor C2, and the other end of filter capacitor C2 is grounded. The corresponding feedback resistors of operational amplifiers A1, A2, A3, and A4 are connected in parallel with filter capacitors C3, C4, C5, and C6, respectively. One end of filter capacitor C7 is connected between the output terminal of operational amplifier A3 and the input terminal of operational amplifier A4, and the other end of filter capacitor C7 is grounded. One end of filter capacitor C8 is connected to the output terminal of operational amplifier A4, and the other end of filter capacitor C8 is grounded. The connection terminal between operational amplifier A4 and filter capacitor C8 serves as the signal output terminal.

[0009] Furthermore, the signal processing module includes an STM32 microcontroller, which includes an AD conversion circuit, a digital filtering module, a power calibration module, and a DA conversion circuit;

[0010] The output terminal of the signal filtering and amplification circuit is electrically connected to the input terminal of the AD conversion circuit, forming a structure in which the output signal of the signal filtering and amplification circuit is processed by the digital filtering module and the power calibration module and then output, or is output through the DA conversion circuit.

[0011] Furthermore, the signal output module includes a display screen and an analog output interface; the display screen is connected to the output terminal of the power calibration module, and the analog output interface is connected to the output terminal of the DA conversion circuit.

[0012] Furthermore, the voltage range of the transmitter's power sampling signal is 0-0.2V.

[0013] Furthermore, the total gain of the signal filtering and amplification circuit is at least 100 times.

[0014] The beneficial effects of this utility model are as follows:

[0015] High-frequency harmonic suppression is achieved through multi-stage capacitor filtering, resulting in high-precision amplification and high-quality digitization of the transmitter power meter. This solves the problems of low accuracy and poor anti-interference of traditional analog meters. Attached Figure Description

[0016] Figure 1 A schematic diagram of the structure of a digital power meter for a broadcast transmitter provided in an embodiment of this application;

[0017] Figure 2 This is a schematic diagram of a signal filtering and amplification circuit provided in an embodiment of this application. Detailed Implementation

[0018] To further illustrate the technical means and effects adopted by this utility model to achieve its intended purpose, the technical solutions in the embodiments of this application are clearly described. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art are within the scope of protection of this application.

[0019] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0020] Please see Figure 1 This application provides a digital power meter for a broadcast transmitter, such as... Figure 1 As shown, it includes: a signal filtering and amplification circuit, a signal processing module electrically connected to the signal filtering and amplification circuit, and a signal output module electrically connected to the signal processing module. Specifically:

[0021] The voltage range of the transmitter's power sampling signal is 0-0.2V;

[0022] See Figure 2 The signal filtering and amplification circuit includes: an LM324N operational amplifier and filter capacitors C1-C8; the LM324N operational amplifier includes op-amps A1, A2, A3 and A4, op-amps A1 and A2 are connected in the form of non-inverting amplifiers to form an input buffer and are connected in parallel to the input terminal of op-amp A3, and the output terminal of op-amp A3 is connected to the input terminal of op-amp A4;

[0023] One end of filter capacitor C1 is connected to the signal input terminal of op-amp A1, and the other end of filter capacitor C1 is grounded. One end of filter capacitor C2 is connected to the signal input terminal of op-amp A2, and the other end of filter capacitor C2 is grounded. The corresponding feedback resistors of op-amps A1, A2, A3, and A4 are connected in parallel with filter capacitors C3, C4, C5, and C6, respectively. One end of filter capacitor C7 is connected between the output terminal of op-amp A3 and the input terminal of op-amp A4, and the other end of filter capacitor C7 is grounded. One end of filter capacitor C8 is connected to the output terminal of op-amp A4, and the other end of filter capacitor C8 is grounded. The connection terminal between op-amp A4 and filter capacitor C8 serves as the signal output terminal.

[0024] The total gain of the signal filtering and amplification circuit is at least 100 times. The input transmitter power sampling signal is between 0-0.2V and contains parasitic high-frequency harmonics. Therefore, a 100x instrumentation amplifier circuit is used to filter and amplify the sampling signal. Through the LM324N operational amplifier and filter capacitors C1 to C8 in the circuit, the high-frequency harmonics in the sampling signal are filtered out, while the sampling signal value is amplified to the 0-2V required by the subsequent microcontroller.

[0025] The signal processing module includes an STM32 microcontroller, which comprises an AD conversion circuit, a digital filtering module, a power calibration module, and a DA conversion circuit.

[0026] The output of the signal filtering and amplification circuit is electrically connected to the input of the AD conversion circuit, forming a structure where the output signal of the signal filtering and amplification circuit is processed by the digital filtering module and the power calibration module before being output, or is output again through the DA conversion circuit. In other words, after the sampled signal is amplified and input to the STM32 microcontroller, it undergoes AD conversion by its internal high-speed AD converter, while simultaneously performing digital filtering and digital power meter calibration. The processed signal is then transmitted to the signal output section. Specifically, the digital filtering module performs digital filtering using software algorithms, and the power calibration module performs power calibration using software algorithms.

[0027] The signal output module includes a display screen and an analog output interface. The display screen is electrically or communicatively connected to the output of the power calibration module, and the analog output interface is electrically connected to the output of the DA conversion circuit. The analog output interface can be configured as a standard digital interface (such as USB) to output power data in digital signal form for external devices to read.

[0028] In practical applications, the power meter of this application can be used for two types of power values: transmitter incident power and reflected power.

[0029] Based on the above technical solution, high-frequency harmonic suppression is achieved through multi-stage capacitor filtering, high-precision amplification from 0-0.2V to 0-2V is realized, and high-quality digitization of the transmitter power meter is achieved, solving the problems of low accuracy and poor anti-interference of traditional analog meters.

[0030] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element. Furthermore, it should be noted that the scope of the methods and apparatuses in the embodiments of this application is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.

[0031] It is understood that the embodiments of this application have been described above in conjunction with the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. As those skilled in the art will know, various changes or equivalent substitutions can be made to these features and embodiments without departing from the spirit and scope of this utility model. In addition, those skilled in the art, under the guidance or instruction of this application, can modify these features and embodiments to adapt to specific situations and materials without departing from the spirit and scope of this utility model. Therefore, this utility model is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are protected by this utility model.

Claims

1. A digital power meter for a broadcast transmitter, characterized in that, include: A signal filtering and amplification circuit, a signal processing module electrically connected to the signal filtering and amplification circuit, and a signal output module electrically connected to the signal processing module; The signal filtering and amplification circuit includes: an LM324N operational amplifier and filter capacitors C1-C8; the LM324N operational amplifier includes operational amplifiers A1, A2, A3 and A4, operational amplifiers A1 and A2 are connected in the form of non-inverting amplifiers to form an input buffer and are connected in parallel to the input terminal of operational amplifier A3, and the output terminal of operational amplifier A3 is connected to the input terminal of operational amplifier A4. The signal input terminal of operational amplifier A1 is connected to one end of filter capacitor C1, and the other end of filter capacitor C1 is grounded. The signal input terminal of operational amplifier A2 is connected to one end of filter capacitor C2, and the other end of filter capacitor C2 is grounded. The corresponding feedback resistors of operational amplifiers A1, A2, A3, and A4 are connected in parallel with filter capacitors C3, C4, C5, and C6, respectively. One end of filter capacitor C7 is connected between the output terminal of operational amplifier A3 and the input terminal of operational amplifier A4, and the other end of filter capacitor C7 is grounded. One end of filter capacitor C8 is connected to the output terminal of operational amplifier A4, and the other end of filter capacitor C8 is grounded. The connection terminal between operational amplifier A4 and filter capacitor C8 serves as the signal output terminal.

2. The digital power meter for a broadcast transmitter according to claim 1, characterized in that, The signal processing module includes an STM32 microcontroller, which includes an AD conversion circuit, a digital filtering module, a power calibration module, and a DA conversion circuit. The output terminal of the signal filtering and amplification circuit is electrically connected to the input terminal of the AD conversion circuit, forming a structure in which the output signal of the signal filtering and amplification circuit is processed by the digital filtering module and the power calibration module and then output, or is output through the DA conversion circuit.

3. The digital power meter for a broadcast transmitter according to claim 2, characterized in that, The signal output module includes a display screen and an analog output interface; the display screen is connected to the output terminal of the power calibration module, and the analog output interface is connected to the output terminal of the DA conversion circuit.

4. The digital power meter for a broadcast transmitter according to any one of claims 1-3, characterized in that, The voltage range of the transmitter's power sampling signal is 0-0.2V.

5. The digital power meter for a broadcast transmitter according to any one of claims 1-3, characterized in that, The total gain of the signal filtering and amplification circuit is at least 100 times.

Images