A high-speed polymer microwave fiber (PMF) communication link is implemented in a 40nm bulk CMOS technology, by making use of two-tone CP-FSK modulation and a carrier frequency of 120GHz. The presented transceiver and enhanced coupler, with a loss of only 3.4dB, allows communication over a distance of 15m at 1.5Gbps. Data rates up to 17.7Gbps were achieved over a link distance of 1m with a BER < 10 −12 . The maximum product of data rate and distance is 60.8Gbps.m over a distance of 8m, resulting in an energy efficiency of only 1.2pJ/bit/m. The transmitter has an output power level of -1.9dBm at 120GHz and a DC power consumption of 11.1mW, the receiver consumes 59.6mW. The transmitter and receiver occupy an active area of respectively 0.025mm 2 and 0.43mm 2 in 40nm CMOS.