Various Nyquist polynomials and their spectral factorizations to obtain suitable finite impulse response (FIR) vestigial sideband (VSB) filters are summarized here. The filters of interest have transfer functions that are polynomials with complex coefficients which are symmetric, due to Lawton, and polynomials whose coefficients are conjugate symmetric or conjugate antisymmetric, which are also...

This paper presents an architecture for generating a high-speed data pattern with precise edge placement (resolution) by using the matched delay technique. The technique involves passing clock and data signals through arrays of matched delay elements in such a way that the data rate and resolution of the generated data stream are controlled by the diierence of these matched delays. This diieren...

Modern fiber optic communications networks multiplex data onto many different channels, each with its own carrier frequency. In order to meet rising demand for high data rates, researchers have begun to consider methods to use the bandwidth of optical fibers more efficiently. In particular, more efficient use might come from operating fewer channels with each channel at a higher data rate, or p...

Future ultra high bit-rate optical time division multiplexed (OTDM) systems may require all-optical demultiplexing to down convert high bit-rate data to e.g. 10 Gbit/s or 40 Gbit/s where electronic circuits can be used. Many suggestions of such demultiplexers have been proposed over the years. The most common device is the nonlinear optical loop mirror (NOLM) that allows switching due to cross ...

A flexible test system is described that has the capability to characterize very high frequency ultrasound transducer arrays up to 128 elements. The system has the capability of testing single element transducers as well as groups of array elements. The R.F. front end electronics consists of pulser circuit, preamp and time gain compensation circuit. The pulser circuit is a high voltage, high sp...

This project describes a Multi-Chip Module (MCM) that contains a microelectronic circuit and a microfluidic device that could be combined to implement a “bacterial microfactory”. The microchip contains two decoders connected to arrays of horizontal and vertical wires respectively, forming a matrix used to process commands received from an external computer. The electrical current flowing throug...

In this paper, we study shared-memory switches under multicast bursty traffic and characterize the relation between their performance and the multicast distribution that defines the mix of multicast traffic arriving at the switches. We consider two schemes that have been used in practical realizations of these switches to replicate multicast cells: 1) replication-at-receiving (RAR), where multi...

The design of demultiplexers based on array waveguides is well known [1-5]. A new design based on the concept of variable waveguide depth was recently reported [6]. Since, the fabrication of channel waveguides on glass, silica or lithium niobate is mostly controlled by the lithography pattern and the subsequent fabrication process, it is difficult to implement the variable depth concept on thes...

Introduction The highest growing sectors of the economy in the last two decades are the informatics and telecommunication. Their development is very correlated, due to the fact that the fast and efficient process of information requires transportation of it with extremly high speed as well. The new technical possibilities led to new applications, which are the base of novel industry sectors. Th...