Broadband phase shifter and vector modulator.

摘要

A broadband phase shifter and vector modulator includes two artificial transmission lines interconnected by FETs to selectively produce and sum incremental phase shifts of an input signal. A number of low pass filter sections are connected in series to form the first of the two artificial transmission lines and a number of high pass filter sections are connected in series to form the second artificial transmission line. Use of low pass and high pass filters equalizes transit times of each phasor through the phase shifter so as to maintain the proper phase relationship between the phasors over a broad bandwidth. Each of the two artificial transmission lines are coupled to a transistor circuit connecting corresponding low and high pass filter sections. The phase shifter operates by selectively summing the output variable-amplitude phase-shifted signals generated within the transmission lines to produce an output signal having a phase shift between 0 DEG and 360 DEG . <IMAGE>