Abstract: An improved arrangement and method for use in a radio communication system is disclosed which makes possible mobile radio channel assignments on narrower channel spacings with a minimum amount of adjacent channel interference or splatter occurring at an included base station receiver. In a first embodiment, the mobile radios modify at least one transmission parameter, such as maximum allowable deviation, a given amount of transmitter output power, and a modulation limiting bandwidth, if a processed value of receive signal strength exceeds at least one predetermined threshold value. The processed value of receive signal strength is taken from a plurality of sampled and stored receive signal strength values in the mobile radio. By determining that the processed value of receive signal strength exceeds a predetermined threshold value, the mobile radio is able to adaptively control the amount of splatter caused at the base station, thus keeping the amount of splatter within acceptable levels.

Abstract: Simulcast distortion in a receiver when using a same-frequency repeater is minimized by applying double modulation to a signal that is broadcast to the same-frequency repeater. A voice signal is applied without delay as AM on a carrier to a modulation index of up to 30%, and the same signal is also applied as FM on the same carrier with a time delay equal to the time delay in the same-frequency repeater. The same-frequency repeater detects the AM and applies the detected signal as FM on a carrier that is rebroadcast. Received FM signals are thus delayed by substantially the same amount whether they are received from the original broadcast or the same-frequency repeater.

Abstract: Spillover of RF signal from the output of a same-frequency repeater to the input is reduced by attaching a tag to the output signal. The tag is double-sideband, suppressed carrier to place two spectral spikes, one above and one below the carrier. The tag is applied to the signal in the IF. A tagged signal of variable amplitude and phase is added to the received signal so as to cancel the tag and hence the spillover signal, leaving only the desired signal. A feedback system controls the amplitude and phase of the cancelling signal.