This paper presents a IJF coding method based on filter shaping, and deduces IJF power spectral density adopting this method.Finally this paper simply introduce FQPSK modulation.

• 本文介绍基于滤波器成形法的IJF编码，并推导基于该法的IJF功率谱密度，在此基础上简要介绍了FQPSK调制体制。