As one of the core components of FM broadcasting transmitter, the controller will directly affect the transmitting quality of FM broadcasting transmitter, and it is an important medium for automatic and digital control of FM broadcasting transmitter. According to the function of FM broadcasting transmitter and the technical requirements of control system, this paper designs the hardware and software of FM broadcasting transmitter controller, hoping to provide some simple reference for the realization of automatic monitoring of FM broadcasting transmitter. The controller of FM broadcasting transmitter is an important device for monitoring the operation status of transmitter. It can realize real-time monitoring and protection of the operation status and fault of transmitter. It mainly has the following functions [1]. Through the switch control module of the controller, the transmitter can be automatically switched on or off or manually controlled. In both automatic and manual modes, the transmitting power of the transmitter will rise automatically after booting, and the monitoring system can automatically recognize and monitor the status of the transmitter switch according to the change of power. At the same time, the user can control the transmitter to switch on and off in time by time parameters. It can detect the real-time running state of each module of FM broadcasting transmitter on-line. Including the real-time detection of the main power supply fault, fan fault, switching power supply fault lamp fault signal and transmitter incident, reflection power, power supply voltage and other analog signals. Data query mainly includes FM broadcasting transmitter real-time operation data, historical operation data, fault records and related data query. It can set various operation control parameters of the system, including switch state parameters, system password, operation rights and other parameters, and also includes the setting of analog correction coefficient and upper and lower thresholds.
When FM broadcasting transmitter is running in practice, it is necessary to detect all kinds of faults in real time, and classify and save the information of the specific types of faults, so as to provide a reliable basis for maintenance personnel to carry out maintenance work. The hardware control system of FM transmitter is based on DCS structure. The main control unit is the core unit of the system. The other control units cooperate with the main control unit to complete the monitoring and operation commands of the system. The hardware structure design not only simplifies the hardware structure and improves the stability of the system, but also optimizes the configuration control function, reduces the workload of the main control unit, and facilitates the maintenance and expansion of the system in the later period. Fig.
1 shows the structure of FM broadcasting transmitter control system. The whole system includes the main control unit and auxiliary control units such as power supply control, switching power supply detection, power amplifier control and so on. The main control unit is the core part of the controller. The rationality of its design will directly affect the performance of the whole controller. The main functions of the main control unit include human-computer interaction, real-time data display, historical data, fault record query, parameter setting and so on. According to the functional orientation of the main control unit, thermostatic element its hardware should include data storage module, clock module, keyboard driver, display and communication module. The main function of the power supply control unit is to collect and judge the analog and switching quantities processed by the switching power supply detection unit, to monitor the working status of the transmitter switching power supply and the preamplifier, and to realize the automatic switching control of the broadcasting transmitter.
According to its functional requirements, it is necessary to communicate with the control unit, accept the operation indicators of the main control unit, and complete the corresponding operation. The power amplifier unit mainly monitors the operation status of the power amplifier box in the broadcasting transmitter, and then collects and converts the analog signals from each group of power amplifier detection units, and transmits the processed signals to the main control unit. The software design of each control unit of FM broadcasting transmitter control system adopts the process software design method. According to the function, the complex control process is divided into several modules, and then multi-module parallel development design is carried out. In this way, not only can the software parts of each module be independently designed to improve the efficiency, but also can ensure the universality and maintainability of the software modules. According to the division of the functions of the main control unit in the control system, the software control process of the main control unit is divided into four control processes: initialization, human-computer interaction, communication and monitoring. Each control process can be divided into several independent functional modules. In the process of designing the software part of the main control unit, all functional modules need to be further refined. For example, the software design workload of human-computer interaction process exceeds 60% of the total software design workload of the main control unit. Therefore, the code may need to be adjusted frequently according to the requirements of the manufacturer in the design process. Therefore, it is divided into several modules to reduce the complexity of the software structure and improve the maintainability of the software. The power supply control unit includes four processes: initialization, data acquisition, data processing and switching machine processing. It completes the control functions of switching power supply analog, fault signal detection and host switching machine command. The software module of power supply control unit is shown in Figure 2. The power amplifier control unit includes three control processes: initialization, data acquisition and data processing. Through these three processes, all analog outputs of the power amplifier box of FM broadcasting transmitter are detected. The software module of the power amplifier control unit is shown in Figure 3. The software and hardware of the control system are equally important. The software part needs to meet the requirements of reliability, understandability, accuracy and easy maintenance. For the software design of FM radio transmitter controller, C language is used. Compared with assembly language, C language has obvious advantages in function, structure, readability and maintainability. The software program of FM radio transmitter controller is written in C language, which improves the flexibility of program design. With various data storage types provided by C language, variable physical storage addresses can be automatically allocated, and the utilization efficiency of RAM space has been further improved [3]. According to the hardware structure of FM broadcasting transmitter control system, the functions of each module are relatively independent. The software design of FM broadcasting transmitter controller is mainly to realize hardware driver and application program. The hardware driver mainly includes chip driver and communication interface driver. The application program is designed separately for each function module according to the functional requirements of broadcasting transmitter, such as switch control program, status monitoring, parameter setting and so on. As one of the core components of FM broadcasting transmitter, the controller needs to test the hardware and software before it is installed to the transmitter, so as to ensure the performance and reliability of the hardware and software of the controller. However, in the process of laboratory testing, the content of the usual test has great limitations. In order to realize the comprehensive test of the controller, it is usually necessary to install it on the broadcasting transmitter for testing. Because of the influence of the factors such as the high power of FM broadcasting transmitter and the difficulty of field test connection, it is necessary to design an efficient and convenient test platform to test the controller of FM broadcasting transmitter, so as to improve the efficiency and accuracy of test and reduce the cost of test. The working environment of broadcasting transmitter is generally faced with such factors as strong radiation, high voltage and strong magnetic field.
Therefore, these interference factors will inevitably affect the operation of broadcasting transmitter. Therefore, it is necessary to ensure that the transmitter has strong resistance to external interference factors. In the process of laboratory testing, the controller is usually intelligently guaranteed the test results in the non-interference environment. Therefore, on-line debugging is needed to ensure the anti-interference ability of the controller and ensure the stable and reliable operation of the controller after it is installed in the broadcasting transmitter. The controller of FM broadcasting transmitter mainly realizes the real-time monitoring and detection of the operation status of the broadcasting transmitter. It can warn the possible faults of the broadcasting transmitter in advance and deal with the sudden faults in time. It is important to ensure the reliable and stable operation of the broadcasting transmitter, reduce the workload on duty and maintain the manual work. Effect. The controller of FM broadcasting transmitter is the inevitable trend of the development of automatic control technology of broadcasting transmitter.
In this paper, the hardware and software of FM radio transmitter controller are designed, and the design of each part is subdivided, which provides a simple reference for related research work.