Her Majesty the Queen in Right of Canada As Represented by the Minister of Industry Through the Communications Research Centre Canada

Nortel Networks Corporation

Philip Vigneron

Colin Brown

Hua Xu

Jason Robert Duggan

The invention relates to a method of non-coherent decoding an encoded CPM signal received by a wireless receiver, and a CPM decoder implementing the method, wherein the signal is generated by a transmitter using a serial concatenation of an outer encoder, an interleaver and an M-ary CPM modulator, and may have a frequency-hopping RF carrier. In a preferred embodiment, the method includes iteratively decoding the received signal by first recursively finding a sub-set of dominant sequences of CPM symbols that maximize a path metric for one hop interval using a non-coherent CPM detector, determining on the basis of this sub-set a sequence of soft inner bits, decoding these soft inner bits with an outer decoder, and using extrinsic information for the soft inner bits provided by the outer decoder to iteratively update the sub-set of dominant sequences of CPM symbols in the inner CPM detector.

Iterative non-coherent CPM decoder

The invention provides an adaptive frequency hopping spread-spectrum (FHSS) transmission system and method, which efficiently utilizes available transmission bandwidth, whilst providing robustness to jamming techniques in wireless communication systems. The proposed technique operates by transmitting a wide-band signal over multiple, single-carrier, parallel transmission subbands, which may occupy non-contiguous frequency regions. The proposed scheme exhibits significant gain in error rate performance, as compared to a data rate equivalent single-subband system in the presence of signal jamming and/or interference without a reduction in the transmission data rate nor an increase in transmitter power. In addition, the proposed system and method are adaptive and enable more efficient use of the available bandwidth for communicating, thus increasing the overall bandwidth utilization of the system.

Frequency hopping communication system

The present invention relates to a new parallel interference cancellation (PIC) configuration where the PIC is implemented after the rake reception and multipath combining. In the invention disclosed, the regenerated interference contributions (functions of signature sequence cross-correlations) for multiuser detection (MUD) in a multipath radio channel are explicitly filtered through the estimated multipath channels, and stored. These stored quantities already contain the effect of the channel, and only need updating according to the rate of change of channel dynamics, and not the symbol period. During each symbol period, interference is computed from each interfering user to each desired user using current estimates of symbol decisions and the aforementioned interference contributions. The precomputation of the interference contributions, which are valid for a sequence of symbols, allows for extremely low complexity baseband processing in the receiver.

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Kanata, Canada

Philip Vigneron