基于FPGA的IRIG-B（AC）时间码解码器的设计

摘要

为了解决IRIG-B（AC）码解码精度低的问题，提高解调系统的稳定性，提出了一种利用高性能FPGA实现解调IRIG-B（AC）码的解码器。通过调用FPGA的IP核生成乘法器与FIR低通滤波器，将B（AC）码中的交流分量滤除掉，然后根据其幅值进行解调。该解码器能够快速准确地解调出IRIG-B（AC）码的时间信息，并输出与此时间信息对应的秒脉冲，通过输出端口将解调出的时间信息传输到上位机显示。通过大量试验证明该解码器准确度高、稳定性强，能够满足各种应用场所对IRIG-B（AC）码授时的要求。%In order to solve the IRIG-B(AC)decoding low accuracy problems and improve the stability of the demod⁃ulation system,a high-performance decoder is presented useing FPGA implementation demodulation IRIG-B(AC) codes.By calling the FPGA IP core generation multipliers and FIR low-pass filter,the AC components in the B(AC) code are filtered,then demodulated according to their amplitude.The decoder can demodulate time information of IRIG-B(AC)code accurately,transmit it quickly,and outputs the second pulse which is corresponding with time in⁃formation,through the output port to the demodulated PC display. Through extensive testing the decoder shows its accuracy,stability,and meets the requirements of various applications for IRIG-B(AC)code of timing.