Kevin R Freisen

US Patent:

55174914, May 14, 1996

Filed:

May 3, 1995

Appl. No.:

8/433188

Inventors:

Peter Nanni - Algonquin IL
Kevin Freisen - Lake Worth FL

Assignee:

Motorola, Inc. - Schaumburg IL

International Classification:

H04B 726

US Classification:

370 29

Abstract:

A method and apparatus to control frequency deviation of a portable transceiver (PT) (122) utilizing a time-division-duplex (TDD) protocol for communicating with a base transceiver (116). The base transceiver (116) transmits (708) a first signal having first deviation levels (706). The PT (122) receives (802) the first signal, measures (808, 810, 824) it to derive estimates of the first deviation levels, and stores (826) the estimates in a memory (322). The PT (122) generates (828) a second signal having second deviation levels (830) controlled by control signal values (323), samples (832) the second signal to derive a second received signal, and appraises (902) the second received signal to derive estimates of the second deviation levels (830). The PT (122) compares (906) corresponding estimates of the first and second frequency deviation levels (830) to derive adjusted control signal values (908) for controlling the second deviation levels (830) to approximate the first deviation levels (706), and thereafter controls (914) the second deviation levels (830) in accordance with the adjusted control signal values (908).