Abstract: A wireless digital telephone system containing at least one emulated base station plus one or more subscriber stations, the emulated base station comprising a station similar to the subscriber station but having the capability of initiating a synchronization process whereby it is enabled to assign time slots to the subscriber station within the frame pattern of an amplitude signal by means of monitoring for positive edges in the signal.

Abstract: In a code-division-multiple-access (CDMA) system employing spread-spectrum modulation, mobile stations initially seek access to a selected one of two or more groups of common packet channels (CPCHs) serviced through a base station. A second order collision resolution phase, conducted between the base stations and contending mobile stations, serves to allocate one or more available channels from the selected group of channels among the contending mobile stations. In the collision resolution phase, each mobile station randomly selects a collision detection (CD) signature and sends that signature in a CD preamble. For each available channel in the group, the base station assigns one of the mobile stations. For each assigned mobile station, the base station transmits a CD acknowledgement that corresponds to the CD preamble of the assigned mobile station and identifies the available channel assigned to that mobile station.

Abstract: A quadrature phase-shift keying modulator produces a QPSK signal which is amplified by a power amplifier. The amplitude gain of the power amplifier is controlled in response to an amplitude difference between the QPSK signal output by the modulator and the amplified QPSK signal output by the power amplifier. A phase detector, connected in series between the modulator and the power amplifier, eliminates amplitude variations from the QPSK signal prior to amplification. A voltage-controlled phase shifter, connected in series between the phase detector and the power amplifier, shifts the QPSK signal in phase by an amount responsive to amplitude information in the QPSK signal.

Abstract: A calibration circuit for a linear channel of an optical modem includes circuitry interconnected to the linear channel for causing the linear channel to oscillate. Circuitry is interconnected to the output of the linear channel for monitoring the bandwidth of the linear channel during oscillation and for generating output pulses. The output pulses are counted and are utilized for generating an adjustment signal applied to the linear channel for adjusting the bandwidth of the linear channel.