A CMOS fully integrated antenna array transmitter with on-chip skew and pulse-delay adjustment for millimeter-wave active imaging

A fully-integrated 8-antenna array transmitter in 65-nm CMOS for short range and portable millimeter-wave (mm-wave) active imaging applications is presented. Each of 8 resistor-less pulse generators (PG) are connected to an on-chip dipole-patch antenna and to a 7-bit digitally programmable delay circuit (DPDC). A 20-bit on-chip jitter and relative skew measuring circuit is also implemented to dynamically calibrate pulse delays for the purpose of beamforming. On-chip skew measurement for eight antenna clocks is performed so that the DPDC's input codes align eight antennas' output pulses. Experimental results of on-chip relative pulse delay calibration and radiation patterns show that beamforming angles of the fully integrated antenna array can be calibrated by digital input codes and the on-chip skew adjustment circuit for active imaging applications.