论文部分内容阅读
为加速海洋科研工作、近来为海上浮标设计了一台遥控指令接收机。接收等幅编码报、码元速率75波特,每次通讯前发射三秒左右同步信号,要求同步时间小于三秒,同步定位(相对)误差E<10%。本文只介绍同步信号提取电路及其改进。图1是同步信号提取环(量化数字锁相环)路方框图。由接收机来的等幅同步脉冲经放大、限幅、滤去干扰,经微分将其前沿负尖脉冲输出,经单稳S及倒相器形成以前沿定位的同步基准脉冲P_s加到鉴相器,同本机同步信号进行相位比较。两者不同步时产生相位误差信号,通过控制电路输出误差脉冲及加、减法指令到数字滤波器(可逆计数器),使计数器在本机同
To speed up marine scientific research, a remote command receiver was recently designed for offshore buoys. Receive equal amplitude code, symbol rate of 75 baud, each communication before the launch of about three seconds synchronization signal, requiring synchronization time is less than three seconds, synchronous positioning (relative) error E <10%. This article only describes the synchronous signal extraction circuit and its improvement. Figure 1 is a synchronous signal extraction loop (quantized digital phase-locked loop) block diagram. The equal-amplitude sync pulse from the receiver is amplified, limited and filtered to eliminate the interference. The front pulse of the negative pulse is output by differentiating, and the leading edge of the synchronous reference pulse P_s is formed by the monostable S and the inverter. Device, with the local synchronization signal phase comparison. Phase error signal generated when the two are not synchronized, the error pulse output by the control circuit and add, subtract instructions to the digital filter (reversible counter), the counter in the local