Research on Loran-C Transmitting System Technology Based on Class-D Power Amplifier

The Objective of this study is to study a new all-solid-state Loran-C transmission technology based on Class-D power amplifiers, and to apply the research results to the “blind compensation” or “enhancement” of the positioning, navigation and timing (PNT) functions of the transmission system, as well as to guide the construction of large-scale transmission stations. The standard Loran-C waveform was theoretically analyzed, modeled and simulated, and the discrete excitation signal for three time periods was generated by pre-distortion modulation technology, and the trapezoidal voltage waveform was superimposed and synthesized by driving the Class-D power amplifiers module to load the antenna tuning network, and finally the standard Loran-C current waveform was formed on the antenna. The results solve the defects of the complex composition of the transmitter of the semi-circular magnetic pulse generator and the high dependence on hardware parameters for the waveform generation method, which makes it difficult to quickly adapt to different transmitting antennas and new systems, improve the transmission efficiency and reduce the operating cost. The Loran-C transmission technology based on Class-D power amplifiers improves the performance of the system from the aspects of new system waveform research, machine efficiency, waveform adaptability and maneuverability, which meets the requirements of the development of a new generation of long-wave navigation timing transmission system in China, and the technology has high military and social application value.