Adjustable Multiphase Sinusoidal Oscillator with Fractionalxe2x80x93Order Elements This paper presents a fractionalxe2x80x93order multiphase oscillator with adjustable FO (Frequency of Oscillation). The oscillator utilizes the following components: CCTA (Current Conveyor Transconductance Amplifier), OTA (Operational Transconductance Amplifier), auxiliary OTRA (Operational Transresistance Amplifier), two FOC (Fractionalxe2x80x93Order Capacitors) and auxiliary resistors. The proposed structure provides three voltage outputs and their inverted variants for three selected values of alpha 0.3, 0.5, and 0.8 of FOC. The FO is tuned by changing the values of the transconductances of the OTA and CCTA. The features of the presented circuit were verified by PSpice simulations with behavioural models of the active elements. Analysis of the dependence of the values of the transconductances on values of alpha and frequency is provided. A THD (Total Harmonic Distortion) and parasitic analysis of the circuit was also made.

Compact RF CMOS 4bit Digitally Controlled Oscillator Design of a reconfigurable compact digitally controlled oscillator (DCO is proposed in this paper. It uses a gyratorC basedtopology tunable active inductor (TAI) that achieves coarse frequency tuning due to a digitally controlled current source and a variable capacitance bank. The DCO, implemented in 130 nm CMOS process, achieves a frequency tuning from 1.8 to 2.6 GHz when varying the digital control word. It occupies an area of only  57 boldsymbolmu mathbfmtimes 53 boldsymbolmu mathbfm . The power consumption is changing from 2.6 mW to 5.3 mW at a supply voltage of 1.1 V, and the phase noise from xe2x88x9286 to xe2x88x9282 dBcHz 1 MHz offset. The proposed DCO shows a compact size, wide tuning and lowpower consumption making it suitable to reconfigurable lowcost multiband radiofrequency (RF) applications.