Lucent Technologies Inc.

Pamela C Kwong

Jeffrey Paul Grundvig

Dale Harvey Nelson

Rajeev Krishnamoorthy

Thomas A Gentles

A method of transmitting a voice communications signal includes the steps of sampling the signal and creating digital representations of the samples. The digital representations are speech-coded to create speech-coded data which is converted to analog symbols. A carrier in the 46-49 MHz band is modulated by the analog symbols and transmitted. A method of receiving a voice communications signal includes the steps of receiving a modulated carrier in the 46-49 MHz band and demodulating the modulated carrier to recover analog symbols. The analog symbols are converted to digital samples, which are then converted to speech-coded data. The speech-coded data are decoded to produce digitized samples, which are converted to analog samples and filtered to produce the voice communications signal. A cordless telephone system according to the invention includes a handset and a base unit. The handset includes a microphone, a speaker, a first digital signal processor connected to the microphone and to the speaker, a first 46-49 MHz RF transceiver connected to the first digital signal processor, and a first antenna connected to the first 46-49 MHz transceiver. The base unit includes a second antenna, a second 46-49 MHz RF transceiver connected to the second antenna, a memory, and a second digital signal processor connected to the second 46-49 MHz RF transceiver, to the memory, and to a telephone line interface.

Method and apparatus for digital cordless telephony

A cascode current mirror for use as a biasing element or as a load device for amplifier stages in which the output resistance is increased so as to produce a substantially lower change in output current as supply voltages vary. The cascode current mirror incorporates an amplifier connected to provide negative feedback on the output cascode transistors in boosting the output resistance by a factor equal to the amplifier gain.

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Whitehall, PA, United States of America

Pamela C Kwong