Photonic Generation of a Dual-Band Polyphase-Coded Microwave Signal With a Tunable Frequency Multiplication Factor

A photonic approach to generate dual-band polyphase-coded microwave signal with a tunable frequency multiplication factor is proposed. The scheme contains a dual-polarization quadrature phase-shift-keying (DP-QPSK) modulator, a polarization modulator (PolM), and a balanced detector. When the bias voltages of the DP-QPSK modulator is properly adjusted, a double-sideband signal will be generated with one sideband along the X polarization of the PolM, with the optical carrier and the other sideband along the Y polarization. Then, the PolM is employed to modulate the optical signal with a phase-coded microwave signal. After the photoelectric balanced detection, polyphase-coded microwave signals with frequency multiplication factors of one, two, and four can be generated. In addition, the proposed scheme can simultaneously produce two phase-coded microwave signals with different carrier frequencies. The proposed system finds a potential application in dual-band radar. In the experiment, a binary- and a quaternary-phase-coded signal with 5.5, 11, and 22 GHz carrier frequencies are generated.