3com Corporation

Analog Devices,inc.

Vitali Vinokour

Vladimir G Parizhsky

Dale M Walsh

Young Han Kim

Alexandre L Leonidov

Benjamin Dolnik

A system and method of widening the synchronization range for a discrete multitone multicarrier single pilot tone system includes detecting a first phase error in a received pilot tone; detecting a second phase error in a received second two bit constellation data channel; converting the second phase error to a first quadrant angle between 0-90&#xb0; and combining the first phase error and the converted phase error to obtain the actual phase error up to and beyond 360&#xb0;.

Method and system for widening the synchronization range for a discrete multitone multicarrier single pilot tone system

Disclosed is an apparatus and method for low complexity, phase independent reception of FSK signals. A finite series of delay elements produces a plurality of equidistant samples of a received FSK signal. The plurality of equidistant samples is processed by an arithmetic unit using a phase independent algorithm to obtain an estimate of the received signal. The estimate of the received signal is then compared to a threshold value to determine if the estimate corresponds to a binary 1 or binary 0, which increments a counter corresponding to each binary value. Multiple estimates are counted over a baud interval of the received FSK signal and a binary 1 or binary 0 is output as a received data signal value depending upon which binary value the counter having the higher value corresponds to.

Low complexity method and apparatus for FSK signal reception

A method and apparatus for determining the correct decision regions in a PCM communication receiver utilizing a public Digital Telephone Network (DTN). A receiver receives samples from an analog loop of the DTN and quantizes the samples according to a reference lattice. The reference lattice defines a set of decision levels representing the quantization level for each PCM codeword. The receiver sets the reference lattice by scaling the lattice to account for the characteristics of the communication channel, which typically includes distortions of the digital data resulting in nonlinear behavior of the channel. The scaling and re-scaling thus accounts for PCM codeword translations or other channel distortion.

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Brookline, MA, United States of America

Vitali Vinokour