Title :
A 26-GHz low-phase-error in-phase-coupled QVCO using modified bi-directional diodes
Author :
Jun-Chau Chien ; Nai-Chung Kuo ; Niknejad, Ali M.
Author_Institution :
Berkeley Wireless Res. Center, Berkeley, CA, USA
Abstract :
This paper presents a new passive coupling technique for quadrature voltage-controlled oscillator (QVCO) with low phase error. The significance of the coupling devices nonlinearity is emphasized. Based on the phase error analysis, modified bi-directional coupling diodes are proposed with higher third-order nonlinearity while lowering the capacitive loading. The proposed prototype and a standard 26-GHz QVCO are fabricated in 65-nm CMOS for comparison. Measurements confirm that the phase error is reduced from 1.5° to 0.36°. Phase error immunity against LC-tank mismatch is significantly reduced.
Keywords :
CMOS analogue integrated circuits; MMIC oscillators; error analysis; field effect MMIC; microwave diodes; voltage-controlled oscillators; CMOS process; LC-tank mismatch; capacitive loading; coupling devices; frequency 26 GHz; low-phase-error in-phase-coupled QVCO; modified bidirectional coupling diodes; passive coupling technique; phase error analysis; phase error immunity; quadrature voltage-controlled oscillator; size 65 nm; third-order nonlinearity; CMOS integrated circuits; Couplers; Couplings; Frequency measurement; Phase measurement; Phase noise; CMOS; phase error; quadrature VCO;
Conference_Titel :
Radio Frequency Integrated Circuits Symposium, 2014 IEEE
Conference_Location :
Tampa, FL
Print_ISBN :
978-1-4799-3862-9
DOI :
10.1109/RFIC.2014.6851712
