Abstract: A method and an apparatus is provided for decoding a communicated radio frequency signal containing a sequence of phase values. The method includes the steps of amplitude limiting the communicated signal and maximum likelihood decoding the amplitude limited signal.

Abstract: A radio communication unit for a digital communication system is provided in which an input information signal is protected from transmission errors by forward error correction encoding the information signal. In addition, the communication unit enhances subsequent processing of a transmitted form of the information signal by a hard-limiting receiver by inserting a predetermined synchronization sequence into the information signal. Further, a corresponding radio communication unit is provided which includes a hard limiting mechanism for removing the magnitude of each sample in a group of data samples of a signal received from over a radio communication channel. In addition, weighting coefficients of the hard-limited group of data samples for maximum likelihood decoding and diversity combining are generated by comparing the hard-limited group of data samples to a known predetermined synchronization sequence.

Abstract: A method and apparatus is provided for synchronizing a received communication signal. A synchronization signal is derived from a received signal having a plurality of synchronization words. Each synchronization word has a predetermined number of synchronization symbols. The synchronization signal is filtered. The filtering is characterized by spacing each filter tap to correspond to synchronization word length increments. Synchronization information is generated which is based on a comparison of the filtered synchronization signal to a threshold. Finally, the synchronization information is output based on a confidence derision derived from the synchronization information.

Abstract: A dual mode radio communication unit for a digital communication system is provided having an error controller including an error detection encoder and a forward error correction encoder which encode an input information signal into an error protected data bit stream. In addition, the communication unit includes a mode selector which enables either the error detection encoder or the forward error correction encoder used with a particular mode of operation of the communication unit. Further, a corresponding dual mode radio communication unit is provided having an error controller for generating estimated information signal samples according to a group of algorithms consisting of either an error detection algorithm or an error correction algorithm. In addition, the corresponding communication unit includes a mode selector for receiving a signal according to a particular one of the group of algorithms which is associated with a particular mode of operation of the corresponding communication unit.

Abstract: A receiver (100) has improved signal weighting parameter estimation. The receiver receives a signal (101) having encoded data. A decision circuit (106) is coupled to the received encoded data to generate a first signal weighting parameter which is used to modify the received encoded data. The modified data is then decoded to output the decoded data. The decoded data output is then re-encoded using a technique similar to that used by the transmitter. The re-encoded data is then used to calculate a second signal weighting parameter which, in turn, is used to modify a stored replica of signal (101). The modified version of the stored replica is then decoded to yield a more accurate estimate of the information contained within the signal (101) at a receiver (100).

Abstract: A diversity receiver (300) has improved diversity weighting parameter estimation. The receiver receives different versions of a signal (101) having encoded data, combines the versions and decodes the data contained within the combination. The decoded data output is then re-encoded using a similar technique as that at a transmitter which transmitted the signal (101). The re-encoded data is then used to calculate a diversity weighting parameter which is used to modify a stored replica each version. The modified versions are then combined and decoded to yield a more accurate estimate of the information contained within the signal (101) at diversity receiver (300).