A wideband receiver employing PWM-based harmonic rejection downconversion

A wideband receiver employing single-stage harmonic-rejection mixers (HRM) is demonstrated. The HRM employs a 3-level PWM representation of a sinusoidal LO in combination with gain-ratios. The PWM LO signal is also used to perform gain control. The receiver gain with harmonic rejection is 26.4-30.1 dB using multi-phase PWM LO and 28-31.8 dB with single-phase PWM LO, for a gain range of 3.7 dB. The DSBNF at highest gain is 5.8 dB. The design demonstrates worst-case HR3/HR5 ratios of 47 and 49 dB without calibration for f
_LO
=100 MHz with a total power dissipation of 41.1 mW.