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一、频率控制系统概述自动频率控制回路在海事卫星通讯系统中作频率补偿用。岸站或船站发射的频率若为固定的,则在传输中会有很大的频率偏移,使接收困难。造成频率偏移的主要因素为卫星中继站频率不稳定性和船舶的运动等。岸站到船站的信号通路如图1所示。
First, the frequency control system Overview Automatic frequency control loop in the maritime satellite communication system for frequency compensation. If the frequency of shore station or ship launch is fixed, there will be a large frequency offset in the transmission, making reception difficult. The main factors causing the frequency offset are frequency instability of the satellite relay station and movement of the ship. Shore station to the station signal path shown in Figure 1.