Optimal GMSK training sequences are generated by applying a base sequence to the in-phase component of the even samples and rotating the base sequence by 2.sup.k-1 and applying the second sequence to the quadrature component of the odd samples. Using the optimal GMSK training sequence a channel estimate can be generated. Filtering the channel estimate converts the channel impulse response to one that can be used with a non-GMSK signal e.g. PSK or QAM.

An interference canceller comprises a composite interference vector (CIV) generator configured to produce a CIV by combining soft and/or hard estimates of interference, an interference-cancelling operator configured for generating a soft projection operator, and a soft-projection canceller configured for performing a soft projection of the received baseband signal to output an interference-cancelled signal. Weights used in the soft-projection operator are selected to maximize a post-processing SINR.

A method is provided for use in a cooperative broadcast multi-hop network that employs broadcast flood routing and multi-hop transmission using a direct-sequence spread-spectrum (DSSS) waveform. DSSS signals are received from other nodes on different channels. ASSW is performed to detect and remove interference signals received on the different channels. MDFT analysis banks each receive a beam in the spectral domain that can be channelized to generate a channelized beam that comprises multiple spectral channels. An adaptive interference mitigation space-frequency whitener module can then be applied to remove interference and generate interference-mitigated spatial-spectral domain channels. MDFT synthesis banks can each perform a MDFT synthesis operation on one of the spatial-spectral domain channels. A multi-user RAKE receiver can then combine the interference mitigated time-domain channelized signals to generate a subset (1 . . . F) of fingers that combine components of transmissions directly received from the other nodes and multipath components of those transmissions.

A method is provided for use in a cooperative broadcast multi-hop network that employs broadcast flood routing and multi-hop transmission using a direct-sequence spread-spectrum (DSSS) waveform. DSSS signals are received from other nodes on different channels. ASSW is performed to detect and remove interference signals received on the different channels. MDFT analysis banks each receive a beam in the spectral domain that can be channelized to generate a channelized beam that comprises multiple spectral channels. An adaptive interference mitigation space-frequency whitener module can then be applied to remove interference and generate interference-mitigated spatial-spectral domain channels. MDFT synthesis banks can each perform a MDFT synthesis operation on one of the spatial-spectral domain channels. A multi-user RAKE receiver can then combine the interference mitigated time-domain channelized signals to generate a subset (1 . . . F) of fingers that combine components of transmissions directly received from the other nodes and multipath components of those transmissions.

A node is provided that is configured to communicate in a cooperative broadcast multi-hop network that employs broadcast flood routing and multi-hop transmission using a direct-sequence spread-spectrum (DSSS) waveform. The node includes an antenna and a waveform module having a receiver processing chain. The antenna can receive a plurality of DSSS signals from other nodes on a particular channel, and output a channel that includes the plurality of DSSS signals. The plurality of DSSS signals include transmissions that are directly received from other nodes and multi-path components of those transmissions. The receiver processing chain can include a multi-user RAKE receiver that can combine, when performing demodulation processing, a plurality of transmissions directly received from the other nodes and multipath components of transmissions received from the other nodes. In some implementations, the node can perform cooperative beamforming and adaptive space-spectrum whitening.

A node is provided that is configured to communicate in a cooperative broadcast multi-hop network that employs broadcast flood routing and multi-hop transmission using a direct-sequence spread-spectrum (DSSS) waveform. The node includes an antenna and a waveform module having a receiver processing chain. The antenna can receive a plurality of DSSS signals from other nodes on a particular channel, and output a channel that includes the plurality of DSSS signals. The plurality of DSSS signals include transmissions that are directly received from other nodes and multi-path components of those transmissions. The receiver processing chain can include a multi-user RAKE receiver that can combine, when performing demodulation processing, a plurality of transmissions directly received from the other nodes and multipath components of transmissions received from the other nodes. In some implementations, the node can perform cooperative beamforming and adaptive space-spectrum whitening.

A receiver is provided that includes a multi-user RAKE receiver that can receive a plurality of transmissions directly received from a plurality of nodes of a cooperative broadcast multi-hop network and multipath components of those transmissions, a combiner module and a data despreader module. The multi-user RAKE receiver includes correlator blocks for each node and a finger selection module. Each correlator block generates one or more candidate fingers for that particular node. The finger selection module can select a subset of the candidate fingers having sufficient correlation for further processing. The combiner module can combine aligned symbols for the subset of candidate fingers to generate and combine soft decisions across each of a plurality of channels into a joint soft decision. The data despreader module can despread chips of information from each of the plurality of channels to generate demodulated data symbols that are converted into data soft-decision bits.

A receiver is provided that includes a multi-user RAKE receiver that can receive a plurality of transmissions directly received from a plurality of nodes of a cooperative broadcast multi-hop network and multipath components of those transmissions, a combiner module and a data despreader module. The multi-user RAKE receiver includes correlator blocks for each node and a finger selection module. Each correlator block generates one or more candidate fingers for that particular node. The finger selection module can select a subset of the candidate fingers having sufficient correlation for further processing. The combiner module can combine aligned symbols for the subset of candidate fingers to generate and combine soft decisions across each of a plurality of channels into a joint soft decision. The data despreader module can despread chips of information from each of the plurality of channels to generate demodulated data symbols that are converted into data soft-decision bits.

A node is provided for a cooperative broadcast multi-hop network that employs broadcast flood routing and multi-hop transmission. The node includes antennas and a waveform module having a receiver processing chain that can include an adaptive space-spectrum whitener (ASSW) module and a multi-user RAKE (mRAKE) receiver. Each antenna can receive output a channel that includes direct-sequence spread-spectrum signals received from other nodes and multi-path components of those transmissions. The ASSW module can perform adaptive space-spectrum whitening to detect and remove interference signals received from each of the channels by performing a covariance analysis to generate channelized signals. The ASSW module can include modified Discrete Fourier Transform (MDFT) analysis and synthesis modules that generate an interference mitigated time-domain channelized signals. The mRAKE receiver, when performing demodulation processing, can combine the interference mitigated time-domain channelized signals to generate fingers that combine components of transmissions received from the other nodes.

A node is provided for a cooperative broadcast multi-hop network that employs broadcast flood routing and multi-hop transmission. The node includes antennas and a waveform module having a receiver processing chain that can include an adaptive space-spectrum whitener (ASSW) module and a multi-user RAKE (mRAKE) receiver. Each antenna can receive output a channel that includes direct-sequence spread-spectrum signals received from other nodes and multi-path components of those transmissions. The ASSW module can perform adaptive space-spectrum whitening to detect and remove interference signals received from each of the channels by performing a covariance analysis to generate channelized signals. The ASSW module can include modified Discrete Fourier Transform (MDFT) analysis and synthesis modules that generate an interference mitigated time-domain channelized signals. The mRAKE receiver, when performing demodulation processing, can combine the interference mitigated time-domain channelized signals to generate fingers that combine components of transmissions received from the other nodes.