Abstract: A controller (152) in a frequency hopped spread spectrum system (100) operating to assign a best available frequency hopping sequence among a plurality of sequences to at least one of a plurality of subscriber units (156) having predefined transmission intervals (12) and predefined transition intervals (14) comprises a power detector (50) that estimates a combination of a noise level and an interference level by measuring signal strength during a series of transition intervals for at least one sequence of channels among the plurality of sequences and a processor that computes an average noise and interference level for the at least one sequence of channels and ranks the at least one sequence of channels in accordance with the average noise and interference level computed.

Abstract: A selective call two-way communication system having a plurality of selective call transceiver units (170) using an inbound channel overlay on an outbound selective call system, the selective call transceiver units comprising a receiver (173) for receiving a message having an address directed to and decodable by the receiver wherein the address (58) points to a vector (60) , a decoder (174) for decoding a pointer within the vector that points to a control information portion (66) within an outbound message portion (67) and for decoding another control information portion (64) for controlling inbound transmissions within an outbound message portion, and a transmitter (172) for transmitting information in accordance with the control information portions. The system further comprises a controller (114) for receiving, formatting and encoding messages having an address wherein the address points to a vector(s) which contains pointer(s) to control information portion(s) within an outbound message portion.

Abstract: Interference removal in spread spectrum signals, comprises the steps at a spread spectrum transmitter (10) of spreading information across a predetermined spectrum by phase modulating a repeating noise sequence (18), providing a spread spectrum signal and transmitting the spread spectrum signal. The method further comprises the steps at a receiver of receiving the spread spectrum signal along with interference (41) multiplying (42) the spread spectrum signal along with interference by a window function (44) providing a multiplied spread spectrum signal. The information is recovered by despreading the multiplied (48) spread spectrum signal using a reciprocal (50) of the spectrum of the repeating noise sequence to obtain a data spectrum with interference and subsequently normalize (52) to obtain a clean data spectrum. Alternatively the information can be recovered by substituting a corrupted magnitude spectrum with a prestored PN sequence magnitude spectrum (70) as shown by receiver (60).