Topic
Voltage-controlled oscillator
About: Voltage-controlled oscillator is a research topic. Over the lifetime, 23896 publications have been published within this topic receiving 231875 citations. The topic is also known as: VCO.
Papers published on a yearly basis
Papers
More filters
18 Sep 2006
TL;DR: An 18mW 90-to-770MHz I/Q synthesizer is fabricated in a 1.2V 0.11mum CMOS process to achieve low power and wide tuning range.
Abstract: An 18mW 90-to-770MHz I/Q synthesizer is fabricated in a 1.2V 0.11mum CMOS process. The architecture is optimized to achieve low power and wide tuning range. A divide-by-3.5 7b VCO with an agile auto-tuning block is included. Phase noise is < -100dBc/Hz at 100kHz offset
49 citations
TL;DR: A dual-band LC voltage-controlled oscillator (VCO) architecture suitable for GSM/PCS/DCS applications is presented that utilizes a fourth-order resonance tank and avoids quality-factor-deteriorating switches.
Abstract: A dual-band LC voltage-controlled oscillator (VCO) architecture suitable for GSM/PCS/DCS applications is presented. The VCO utilizes a fourth-order resonance tank and avoids quality-factor-deteriorating switches. The paper outlines the design tradeoffs and the VCO when using a fourth-order resonator. The 0.8-GHz/1.8-GHz test chip was fabricated in the 0.5-mum IBM-5AM SiGe process and has achieved phase noise of -134 dBc/Hz at a 1-MHz frequency offset from the carrier, with 56-MHz and 121-MHz tuning ranges in the corresponding bands. The VCO core consumes 15 mW from a 2.5-V power supply
49 citations
TL;DR: In this article, the authors focused on the noise elimination at a selected frequency from the line voltage of a two-level three-phase inverter, when it is driven by random space-vector pulsewidth modulation.
Abstract: This study has focused on the noise elimination at a selected frequency from the line voltage of a two-level three-phase inverter, when it is driven by random space-vector pulse-width modulation. Distribution of noise power in a wide range of frequencies in the conventional random pulse-width modulation (RPWM) methods may cause system resonant frequency excitation. Therefore, it can increase the acoustic noise and vibration in loads of inverters, especially ac motors. Thus, for the effective utilization of RPWM techniques, it is necessary to cancel noise at a specified frequency. The proposed method is able to create a gap in the spectrum of the line voltage at a selective frequency in the human hearing range. Therefore, unlike conventional RPWM techniques, switching periods are determined based on the position of the rotary reference vector. The presented relation between switching periods and the reference vector is used for the conventional space-vector pulse-width modulation (SVPWM) and two-phase SVPWM. The simulation and experimental results confirm that the proposed method effectively creates a gap at the selected frequency in power spectrum density of the line voltage of the three-phase inverter using random SVPWM.
49 citations
TL;DR: A memristor-based voltage-controlled reactance-less oscillator VCO is introduced as an application for the proposed circuits which is nano-size and more efficient compared to the conventional VCOs.
Abstract: This paper introduces two voltage-controlled memristor-based reactance-less oscillators with analytical and circuit simulations. Two different topologies which are R-M and M-R are discussed as a function of the reference voltage where the generalized formulas of the oscillation frequency and conditions for oscillation for each topology are derived. The effect of the reference voltage on the circuit performance is studied and validated through different examples using PSpice simulations. A memristor-based voltage-controlled oscillator VCO is introduced as an application for the proposed circuits which is nano-size and more efficient compared to the conventional VCOs. Copyright © 2013 John Wiley & Sons, Ltd.
49 citations
Patent•
[...]
13 Dec 1976
TL;DR: In this article, a phase synchronizing system with a dual mode of operation for use with modified frequency modulation (MFM) encoded signals is presented, where the captive range is assured by providing a first frequency locking mode where a voltage controlled oscillator (VCO) is first locked in frequency to a reference signal and subsequently locked in phase to an MFM signal independently of the frequency assumed by the latter signal.
Abstract: A phase synchronizing system having a dual mode of operation for use, for example, with "modified frequency modulation" (MFM) encoded signals wherein captive range is assured by providing a first frequency locking mode of operation wherein a voltage controlled oscillator (VCO) is first locked in frequency to a reference signal and a second phase locking mode of operation wherein the VCO is subsequently locked in phase to an MFM signal independently of the frequency assumed by the latter signal.
49 citations