In this paper, a nontrivial uncorrelated phase noise analysis is proposed for frequency synthesizer of a passive millimeter-wave Synthetic Aperture Interferometric Radiometer (SAIR) imager named BHU2D-U designed for concealed weapon detections on human bodies with high imaging rates. This synthesizer provides local oscillators both for millimeter-wave front-ends and intermediate frequency IQ de...

In this paper we examine the use of an HMM-based polyglot synthesizer for languages for which very limited or no speech data is available. In a former study, we presented a system that combines monolingual corpora from several languages to create a polyglot synthesizer. With this synthesizer we can synthesize any of the languages included in the training data with the same output voice and spee...

Phase locked loops (PLL) are used in almost every communication system. Some of the uses include recovering clock from digital data signals, performing frequency, phase modulation and demodulation, recovering the carrier from satellite transmission signals and as a frequency synthesizer. It is very well known that there are many designs in communication that require frequency synthesizers to ge...

A scheme of frequency hopping spread spectrum (FHSS) frequency synthesizer suitable for synthesis of radio-frequency (RF) carrier signal in very high frequency (VHF) band is proposed, implemented and tested. The synthesizer is based on the direct digital frequency synthesis (DDFS or DDS) and phase locked loop (PLL) with dynamic monitoring of varicap’s voltage to reduce switching time. The resul...

A quantization noise reduction technique is proposed that allows fractional-N frequency synthesizers to achieve high closed loop bandwidth and low output phase noise simultaneously. Quantization induced phase noise is the bottleneck in state-ofthe-art synthesizer design, and results in a noise-bandwidth tradeoff that typically limits closed loop synthesizer bandwidths to be <100kHz for adequate...

In this paper, we address the issue of choice of unit size in unit selection speech synthesis. We discuss the development of a Hindi speech synthesizer and our experiments with different choices of units: syllable, diphone, phone and half phone. Perceptual tests conducted to evaluate the quality of the synthesizers with different unit size indicate that the syllable synthesizer performs better ...

In this paper, we address the issue of choice of unit size in unit selection speech synthesis. We discuss the development of a Hindi speech synthesizer and our experiments with different choices of units: syllable, diphone, phone and half phone. Perceptual tests conducted to evaluate the quality of the synthesizers with different unit size indicate that the syllable synthesizer performs better ...

Title: Frequency synthesis for cognitive multi-radio

This paper presents a low power CMOS frequency synthesizer for GPS application that can support multiple reference clocks. The frequency synthesizer has fractional-N phase locked loop structure with sigma-delta modulator to allow multiple reference clock frequencies. The measured phase noise is -126dBc/Hz at 1MHz offset from the carrier. This chip is fabricated with 0.18 m CMOS technology, and ...