A 52 Gb/s 8.9-dBm EIRP 300-GHz-Band Amplifier-Last Outphasing Transmitter With Path Mismatch Calibration in 65-nm CMOS

This article presents a 300-GHz-band amplifier-last outphasing phased-array transmitter with path mismatch calibration in a 65-nm CMOS technology. Calibration is essential for mitigating impairments in outphasing systems used for wideband communication. The transmitter integrates two independent sub-THz LO generation chains to calibrate the phase mismatch between two paths and configure the phase delay between different phased-array elements. An integrated RF outphasing amplifier calibrates the amplitude mismatch and improves the transmitter’s effective isotropic radiated power (EIRP). After calibration, the transmitter exhibits a 3.3-dB improvement in error vector magnitude and supports 16QAM modulation at 52Gb/s over a distance of 9cm. It achieves a peak EIRP of 8.9dBm at 246GHz, with a minimum EIRP of 5.0dBm across the frequency range from 237 to 250GHz. An 8×1 phased-array transmitter is implemented, demonstrating a main lobe scanning range of ±12° in the$E$-plane.