A high-frequency divide-by-256–271 programmable divider is presented with the improved timing of the multi-modulus divider structure and the high-speed embedded flip-flops. The D flip-flop and logic flip-flop are proposed by using a fast pipeline technique, which contains single-phase, edge-triggered, ratioed, and high-speed technologies. The circuits achieve high-speed by reducing the capaciti...

A 1 V low voltage delta-sigma fractional-N frequency divider for multi-band (780/868/915 MHz and 2.4 GHz) WSN frequency synthesizers is presented. The frequency divider consists of a dual-modulus prescaler, a pulse-swallow counter and a delta-sigma modulator. The high-speed and low-voltage phase-switching dualmodulus prescaler is used in the frequency divider. Low threshold voltage transistors ...

This paper deals with maximizing the spurious free dynamic range (SFDR), while minimizing the power consumption of sine-wave approximation circuits used in direct digital frequency synthesizers (DDFSs). A novel 16-segment parabolic approximation is detailed and compared with other recent solutions. The circuit complexity (as number of transistors) is comparable to that of ultra low-power 16-seg...

Based on the parabolic approximation, which was recently introduced by the authors, a new architecture for sine-output direct digital frequency synthesizers has been developed. Due to using this approximation, and also considering several memory-reduction techniques, the proposed architecture is so designed that needs only 728 bits read-only memory for mapping a 12-bit phase address to 10-bit s...

Prosody model used in the syllable based speech synthesizer DEMOSTHENES is described in the paper. The paper focuses on the segmental structure, especially on the segmentation into rhythm units (prosodic phrases). Relations between prosodic segments and sentence constituents are also discussed.

Dual modulus prescaler is one of the main building blocks in Frequency synthesizers. Which gives the flexibility to select channels on the basis of the number of times each of the modulus is selected. Modern frequency synthesizer requires high speed, low power prescaler. This paper proposes the design of such a prescaler using the carbon nanotube based transistor. The two most important perform...

Direct digital synthesizers provide broadband and flexible signal generation. Hence, they are well suited for radar applications. In this paper, we consider the EUVIS DS872 device that has a bandwidth of 3GHz and an internal memory. The goal of this work is to evaluate its usability in frequency modulated continuous wave (FMCW) radar systems. An experimental test environment has been created, w...

of this new trend. The special issue of Journal of Phonetics1 is another manifestation of the current interest in speech synthesis research. SYNTHESIZERS AND CONTROL PARAMETERS We currently have a number of different classes of synthesizers in our systems. The long term goal of having articulatory synthesis is also attracting considerable research effort. It is generally agreed upon that the ul...