Compact Full-Duplex Amplify-and-Forward Relay Design for 5G Applications

This paper presents a compact circuit design for implementing full-duplex relays serving network architectures envisioned for 5G applications. The proposed design prevents the transmit signal from interfering with the received signal through signal inversion. Signal inversion is accomplished through a compact design based on parametric amplifier circuit which operates simultaneously in two different modes, re-transmit and demodulate. This design also has an added advantage of being capable of generating phase difference between the transmitted and received signals by controlling the local oscillator signal. The validity of the design is evaluated against an example Smart Grid architecture, where it is employed to function as amplify-and-forward full-duplex relays/repeaters for serving several communication links. Simulation results indicate that full-duplex mode outperforms half-duplex one in terms of average channel capacity as well as bit error rate irrespective of the position of the relays with respect to distance from source/destination.