A simple filter-less QPSK modulated vector millimeter-wave signal generation with frequency quadrupling only enabled by a DP-PolM

In this work, a new and simple frequency quadrupling scheme of generating quadrature phase shift keying (QPSK) modulated vector millimeter-wave signal based on a dual-parallel polarization modulator is proposed, which can avoid the problem of Mach–Zehnder modulator (MZM) offset point drifting. To eliminate constellation overlapping of the generated vector millimeter-wave signal caused by phase multiplication in the process of frequency multiplication, precoding assisted technique is adopted. The principle and feasibility of the proposed scheme is deduced by detailed mathematical formula. Simulations are done to generate 40 GHz QPSK modulated vector millimeter-wave signals using a 10 GHz radio frequency source and the BER performance is analyzed in detail. The results show that BER of the generated 5/10-Gbit/s vector millimeter-wave signal is below 3.8 × 10^ - 3 , when the input optical power for into photo-detector is higher than − 24.25 dBm.