Nortel Networks Corporation

Northern Telecom Limited

Northern Electric Company Limited

Miles A Copeland

Sorin P Voinigescu

Thomas A Riley

David Marchesan

A method and apparatus for performing image rejection filtering in a radio signal processing device. In a specific example of implementation, the apparatus is a radio transceiver that includes a transmitter and a receiver, each comprising an image rejection filter. A control signal, already available in the usual radio transceiver architecture, is used to simultaneously tune the LO frequency of the transceiver and the image rejection frequency of the image rejection filters. The image rejection filters are designed such that their image reject frequency accurately tracks the Local Oscillator (LO) frequency of the transceiver over a range of frequencies.

Method and apparatus for performing image signal rejection

Delta-sigma fractional-N frequency synthesizer and frequency

An analog signal processor in which the voltage is sensed across a plurality of charge storage elements to derive an output signal. With this arrangement, the effects of signal interaction encountered in charge sensing are eliminated. The processor can be readily implemented using MOS (metal-oxide-silicon) technology whereby the charge is manipulated by electronic data and stored at the surface of the semiconductor substrate. It is particularly adapted for use as a programmable cross-correlator or a transversal filter.

Analog signal processor

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Ottawa, Canada

Miles A Copeland