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.
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TL;DR: In this paper, a fully integrated 5GHz phase-locked loop (PLL) based frequency synthesizer is designed in a 0.24 /spl mu/m CMOS technology.
Abstract: A fully integrated 5-GHz phase-locked loop (PLL) based frequency synthesizer is designed in a 0.24 /spl mu/m CMOS technology. The power consumption of the synthesizer is significantly reduced by using a tracking injection-locked frequency divider (ILFD) as the first frequency divider in the PLL feedback loop. On-chip spiral inductors with patterned ground shields are also optimized to reduce the VCO and ILFD power consumption and to maximize the locking range of the ILFD. The synthesizer consumes 25 mW of power of which only 3.8 mW is consumed by the VCO and the ILFD combined. The PLL has a bandwidth of 280 kHz and a phase noise of -101 dBc/Hz at 1 MHz offset frequency. The spurious sidebands at the center of adjacent channels are less than -54 dBc.
250 citations
TL;DR: This paper describes a new type of frequency modulation, called Tamed Frequency Modulation (TFM), for digital transmission, where the desired constraint of a constant envelope signal is combined with a maximum of spectrum economy which is of great importance, particularly in radio channels.
Abstract: This paper describes a new type of frequency modulation, called Tamed Frequency Modulation (TFM), for digital transmission. The desired constraint of a constant envelope signal is combined with a maximum of spectrum economy which is of great importance, particularly in radio channels. The out-of-band radiation is substantially less as compared with other known constant envelope modulation techniques. With synchronous detection, a penalty of only 1 dB in error performance is encountered as compared with four-phase modulation. The idea behind TFM is the proper control of the frequency of the transmitter oscillator, such that the phase of the modulated signal becomes a smooth function of time with correlative properties. Simple and flexible implementation schemes are described.
247 citations
TL;DR: In this article, a low-cost microwave oscillator is proposed, which makes use of a substrate integrated waveguide (SIW) cavity that acts as a frequency selector as well as a feedback-coupling device.
Abstract: A topology is proposed for designing a low-cost microwave oscillator. This new feedback oscillator makes use of a substrate integrated waveguide (SIW) cavity that acts as a frequency selector as well as a feedback-coupling device. The oscillator is stabilized by using an injection-locking scheme. A 12.02-GHz oscillator prototype was designed. Experimental results for phase noise, locking range, and quality factor of the new circuit are presented. An external Q of 178 was measured.
246 citations
TL;DR: In this article, a phase-locked loop (PLL) was used for fractional-N frequency synthesis using oversampling A/D conversion technology, allowing the spectrum of error energy to be shaped so that fractional synthesis error energy is pushed away from the carrier.
Abstract: Fractional-N frequency synthesis using a phase locked loop (PLL) is considered. Advances in oversampling A/D conversion technology are incorporated into fractional-N synthesis, allowing the spectrum of error energy to be shaped so that fractional synthesis error energy is pushed away from the carrier. Based on this new technology, a CMOS integrated fractional-N divider was successfully developed. A complete fractional-N PLL was constructed utilizing only a CMOS divider, a dual modulus prescaler, a simple loop filter, and a voltage controlled oscillator (VCO). The resulting PLL exhibits no fractional spurs. >
243 citations
TL;DR: In this article, a local oscillator phase-shifting approach is introduced to implement a fully integrated 24-GHz phased-array receiver using SiGe technology, which achieves state-of-the-art performance.
Abstract: A local-oscillator phase-shifting approach is introduced to implement a fully integrated 24-GHz phased-array receiver using SiGe technology. Sixteen phases of the local oscillator are generated in one oscillator core, resulting in a raw beam-forming accuracy of 4 bits. These phases are distributed to all eight receiving paths of the array by a symmetric network. The appropriate phase for each path is selected using high-frequency analog multiplexers. The raw beam-steering resolution of the array is better than 10deg for a forward-looking angle, while the array spatial selectivity, without any amplitude correction, is better than 20 dB. The overall gain of the array is 61 dB, while the array improves the input signal-to-noise ratio by 9 dB
241 citations