Abstract

A novel scheme to generate microwave frequency shift keying (FSK) signals is proposed and verified by a simulation. The main devices are two single-drive Mach Zehnder modulators (MZM) and a commercial phase modulator (PM). They are parallelly settled to perform the FSK signal generation. In this simulation work, two MZMs are driven by the RF signals with a phase difference which is introduced by an electrical phase shifter (EPS). Simultaneously, the PM is driven by a binary coding signal. The simulation results show that when the two MZMs are biased at the maximum transmission point (MATP), a microwave FSK signal can be obtained with the frequency is two times as large as the RF frequency for bit ‘0’ and four times as large as the RF frequency for bit ‘1’, respectively. It should be noted that the system shows excellent adaption to the non-ideal extinction radio and the inherent inaccurate phase shift of the electrical phase shifter. Therefore, the generated microwave FSK signal can meet the requirement of high-frequency applications.

© 2018 The Author(s)