Abstract: An improved mapping policy, signal mapper, transmitter, receiver, and communication system are introduced. The improved signal mapping policy alternates between standard and inverted bit mapping functions at selected phase states to reduce the error coefficient of MSK and other types of CPFSK signals. The proposed policy can more generally be applied to other types of signals with memory as well. Simulations show that the mapping policy can significantly improve performance particularly at lower to moderate SNR values.

Abstract: The present invention centers upon uplink communication protocols for use primarily with orthogonal frequency division multiple access (OFDMA) communication systems. Aspects of the invention relate to narrow band frequency division multiplexed (NBFDM) modulation protocols primarily for uplink usage in asymmetric OFDMA communication systems. In particular, NBFDM uplinks that use quadrature multiplexed continuous phase modulation are detailed and noncoherent detection schemes are developed to process the uplink channel signals without the need to transmit uplink phase reference signals. Other aspects of the invention relate to burst mode uplink communications in OFDMA systems such as those involving opportunistic beamforming.

Abstract: A class of bandwidth reduction techniques are used develop a broad class of modulation types collectively called SSB-FM. These signals can be used to construct communication systems that provide bandwidth-normalized performance gains of 10 dB or more when compared to popular prior art modulation methods. An aspect of the invention involves mapping trellis paths in a complex signal space onto corresponding real-valued trellis signals with desirable spectral properties. The invention can be used map continuous phase modulated (CPM) signals onto simpler amplitude-modulated trellis signals having double the channel capacity of prior art CPM signals. Multi-amplitude signaling and frequency division multiplexing may also be incorporated to further accommodate more information per symbol.

Abstract: Binary data signal multi-line interval encoding and decoding arrangements supporting high speed data communications consistent with certain embodiments produce a signal having a plurality of pulses with a minimum pulse duration of T. The pulses are arranged in a signal pattern selected as one of M possible signal patterns of L bits transmitted over N time intervals, with each time interval being of T seconds in duration, to represent one of M possible message sequence, where M>2N. The plurality of pulses have transitions that occur at times falling between the boundaries of the time interval T. Embodiments may be implemented in hardware, with a computer executing a software program within, or with both. This abstract is not to be considered limiting, since other embodiments may deviate from the features described in this abstract.