125 GHz wireless transmission of 10 GBaud/s Nyquist-QPSK signal using p-i-n broadband transmitter and FMB envelope detector

This study experimentally demonstrated a simple, low-cost terahertz wireless communication network that is fully compatible with radio-over-fiber technology. In this experiment, quadrature phase-shift keying (QPSK) modulation, 8-quadrature amplitude modulation(8-QAM), and 16-QAM formats are utilized to send orthogonal frequency-division multiplexing (OFDM) signals over 30 – 150 cm wireless link distances. Here, a broadband p-i-n photodiode upconverts the signals to 125 GHz frequency on the transmitter side, and a fermi-level managed barrier (FMB) diode down-converts the received sub-THz waves on the receiver side. The results indicate that 20 Gbps data rate under 7% FEC limit condition can be successfully transmitted over a 30 cm wireless link distance.