In this paper, a low overhead phase noise cancellation technique for ring oscillator (RO)-based quadrature receivers is presented. The proposed technique operates in background and extracts RO phase noise as well as supply-induced phase noise from the digital phase-locked loop. The obtained phase noise information is then used to restore the randomly rotated baseband signal in digital domain. A receiver prototype is fabricated in standard 65-nm CMOS technology. It demonstrates a phase noise reduction from-88 to-109 dBc/Hz at 1-MHz offset and an integrated phase noise reduction from-16.8 to-34.6 dBc when operating at 2.4 GHz.
- Digital phase-locked loop (DPLL)
- frequency synthesizer
- phase noise cancellation
- radio receiver
- ring oscillator (RO)
- sub-sampling time-To-digital converter (TDC)