Fig. 1. Schematic diagrams of generating single sideband signal by Hilbert transform. (a) USB; (b) LSB

Fig. 2. Schematic diagram of OFDM vector mm-wave generation based on two-phase modulator

Fig. 3. Spectra at various locations in process of generating vector millimeter waves. (a) Electrical spectrum of RF OFDM vector signal after up conversion; (b) electrical spectrum after superposition of two RF signals; (c) optical spectrum of output signal of laser; (d) optical spectrum of output signal of phase modulator PM-a; (e) optical spectrum of output signal of phase modulator PM-b; (f) optical spectrum after coherent superposition of output signals from two phase modulators; (g) selected ±1st o

Fig. 4. Measured BER versus received optical power for 2.5/5-Gbaud/s QPSK modulated OFDM vector mm-wave signals in BTB and after 10-km SMF transmission. Inserts Ⅰ and Ⅱ are received QPSK constellations when received optical powers are -21.5 dBm and -19.6 dBm, respectively

Fig. 5. Measured BER results versus phase deviation drift for 5-GBaud/s QPSK modulated OFDM vector mm-wave signals in BTB transmission case. Inserts Ⅰ and Ⅱ are output optical spectra after dual-parallel phase modulator when phase deviation drifts are 0° and 30°, respectively