Title :
A 1-V 27mW 10-GHz LC-NOR-Ring QVCO for UWB-OFDM Direct Frequency Synthesizer
Author :
Lin, Chien-chih ; Wang, Chorng-Kuang
Author_Institution :
Dept. of Electr. Eng., Nat. Taiwan Univ., Taipei
Abstract :
This paper proposes an LC-NOR-ring quadrature voltage controlled oscillator (QVCO). Applied to the direct frequency synthesizer used in the frequency-hopped MB-OFDM UWB system, the ring is designed to enhance quadrature phase accuracy. To prevent from the inactive equilibrium state in an even-numbered delay-stage ring, the QVCO comprises four stages of NMOS-NOR gates that stimulate oscillation and equip with low-voltage operation capability. Inductor loads are used in accompany with the varactors to reduce the power consumption. Realized in a 0.18-mum 1P6M CMOS process, the circuit draws 27-mA current from a 1-V supply. The core circuit occupies an area of 1.012 times 0.35mm2 . The measured oscillation frequency shows that the QVCO has the range of 9.7GHz to 10.6GHz. The phase noise performance is above -90dBc/Hz from 10-kHz offset in the wideband sense
Keywords :
CMOS integrated circuits; OFDM modulation; frequency hop communication; frequency synthesizers; inductors; microwave oscillators; phase noise; ultra wideband communication; varactors; voltage-controlled oscillators; 0.18 micron; 1 V; 1P6M CMOS process; 27 mA; 27 mW; 9.7 to 10.6 GHz; LC-NOR-ring QVCO; LC-NOR-ring quadrature voltage controlled oscillator; MB-OFDM UWB system; NMOS-NOR gates; UWB-OFDM; delay-stage ring; direct frequency synthesizer; frequency hopping; inactive equilibrium state; phase noise performance; quadrature phase accuracy; CMOS process; Circuits; Delay; Energy consumption; Frequency measurement; Frequency synthesizers; Inductors; Phase noise; Varactors; Voltage-controlled oscillators;
Conference_Titel :
Asian Solid-State Circuits Conference, 2005
Conference_Location :
Hsinchu
Print_ISBN :
0-7803-9162-4
Electronic_ISBN :
0-7803-9163-2
DOI :
10.1109/ASSCC.2005.251759
