In a system comprising a first base station (B1) assigned with a control channel frequency, a counterpart mobile station (P1) of the first base station, and a second base station (B2) adjacent to the first base station and assigned with the control channel frequency, the first base station comprises a control information transmitting portion (1, 5) for intermittently transmitting control information signals through the control channel frequency to the counterpart mobile station with a time durat...

A mobile communications system for permitting the communications of a mobile unit in proximity to a communications service having priority over the communications of the mobile unit. An interference zone is formed around the priority communications site such that if the mobile unit were to transmit in the frequency band of the priority system, interference would be created with the operation of the priority receiver. In order to eliminate interference with the priority system by the mobile unit,...

An interference cancelling system for cancelling or minimizing multiple signal components of a received signal in a radio receiver caused by an interfering signal from a radio transmitter which interfering signal follows multiple paths to the radio receiver includes a directional coupler which samples the interfering signal transmitted from the radio transmitter and provides a primary sample signal, a transmission link which defines a primary sample signal path from the radio transmitter to the ...

A method for linearizing amplifiers by measuring the intermodulation products at the output of the linearized amplifier using minimum additional hardware without the performance problems associated with pilot tones. In one embodiment, the amplifiers are adaptively linearized using performance monitoring radios. Specifically, the performance monitoring radios are used to measure the signal levels of the intermodulation products in unused communication channels. Such measurements are then used to ...

A handover technique in a cellular radio communication system (100) for handing over a radio (102) from a first channel in a first cell to a second channel in a second cell, the technique comprising generating a fill-in message extrapolated from a message of the radio on the first channel and communicating the fill-in message when the radio has ceased communicating on the first channel; and terminating the fill-in message when the radio begins communicating on the second channel, thereby reducin...

Apparatus, and an associated method, for facilitating selection of optimal antenna weightings by which to weight signals sent in a communication system that utilizes closed-loop transmit diversity. A deterministic perturbation gradient approximation technique is utilized in which perturbation vectors are selected by a selector and applied, by an applicator, to antenna weighting elements. A selected set of perturbation vectors are applied to the antenna weighting elements in both a positive direc...

A method and apparatus eliminates an audible noise burst after reestablishment of an external timing signal in a radio base station (102). After a loss of the external timing signal, the base station (102) temporarily operates from an internal timing signal generator (226) to provide digital communications over a radio link (106) with a portable communication unit (120). After reestablishment of the external timing signal, the base station (102) detects (304) the presence of the signal, waits (3...

Intelligible crosstalk in microwave radio systems employing single-sideband modulation is substantially eliminated by phase-modulating the AM carrier-wave prior to its modulation by the baseband signal. The phase-modulation may comprise a periodic signal, such as a single sinusoidal tone or pseudo-random noise, or it may comprise an aperiodic signal such as a truly random noise. In this latter event, the coding signal is transmitted to the receiving location to ensure proper demodulation of the ...

A frequency cancelling system is disclosed which improves reception of a communication signal which is transmitted at a communication frequency in the presence of an interference signal which occurs at the same communication frequency. The frequency cancelling system generates a reference signal at the communication frequency, and adjusts the reference signal to be opposite in phase and equal in amplitude to the interference signal. The reference signal and the communication signal are then comb...

A method of reducing interference within a cellular system (10) by partitioning a designated frequency spectrum within a service coverage area (11, 12, 13, 14, 15, 16, or 17) into a first and at least second spectrum inclusive of the designated frequency spectrum and each with an associated power level. Assignment of communication units to a spectrum and power level are based upon distance from the base site (as determined through signal strength measurements). The spectral content of spectra in...