Adaptive communications methods for multiple user packet radio wireless networks

A base station receiver system for recovering a plurality of data streams from a plurality of signals, each signal transmitted from a corresponding one of a plurality of remote units in a radio communication network, comprising:

• a receiver coupled to receive said signals, said receiver forming an input data matrix;
• a demultiplexer coupled to receive said input data matrix, said demultiplexer separating said input data matrix into a preamble data matrix and an information data matrix;
• a matrix decomposition processor coupled to receive said preamble data matrix and providing a first decomposition matrix and a second decomposition matrix, wherein said first decomposition matrix is substantially orthogonal and said second decomposition matrix is substantially upper triangular;
• a multiplier using element by element multiplication of a base code vector with said first decomposition matrix and providing a descrambled matrix;
• a detector with an input for said descrambled matrix and using a set of substantially orthogonal preamble vectors to provide a set of detected preamble correlation vectors, wherein said each detected preamble correlation vector corresponds to one of said plurality of remote units;
• a weight vector generator coupled to receive said second decomposition matrix and said detected preamble correlation vectors and providing a set of weight vectors, wherein each of said weight vectors is computed using a corresponding one of said set of detected preamble correlation vectors;
• and
• a despreader coupled to receive said information data matrix and said set of weight vectors and providing a set of despread symbol vectors, wherein each detected despread symbol vector corresponds to one of said plurality of remote units.

A remote unit receiver system for recovering a data stream from a signal transmitted from a base station in a radio communication network, comprising:

• a receiver coupled to received said signal, said receiver forming an input data matrix;
• a demultiplexer having an input coupled to receive said input data matrix, wherein said demultiplexer separates said input data matrix into a preamble data matrix and an information data matrix;
• a matrix decomposition processor coupled to receive said preamble data matrix and providing a first decomposition matrix and a second decomposition matrix wherein said first decomposition matrix is substantially orthogonal and said second decomposition matrix is substantially upper triangular;
• a correlator coupled to receive said first decomposition matrix and providing a correlation vector, wherein said correlation vector is a cross-correlation of said first decomposition matrix and a preamble vector uniquely associated with said remote unit;
• a weight vector generator coupled to receive said second decomposition matrix and said correlation vector and providing a weight vector;
• and
• a despreader coupled to receive said information data matrix and said weight vector and providing a despread symbol vector.

A method for communicating a data stream from a base unit to a destination remote unit in a radio communication network, comprising the steps of:

• mapping said data stream to a sequence of information symbols;
• selecting a unique preamble for said destination remote unit;
• concatenating said preamble with said sequence of information symbols to form a concatenated signal;
• spreading said concatenated signal using a base spreading weight vector associated with said destination remote unit to form a spread signal;
• transmitting said spread signal;
• receiving said spread signal at said destination remote unit to form an input data matrix;
• separating said input data matrix into a preamble data matrix and an information data matrix;
• detecting said preamble in said preamble data matrix;
• and
• applying a remote unit despreading weight vector to said information data matrix to form a sequence of information symbol estimates.

A base station receiver system for recovering a plurality of data streams from a plurality of signals, each signal transmitted from a corresponding one of a plurality of remote units in a radio communication network and each signal having a preamble portion and an information data portion, comprising:

• a receiver coupled to receive said signals, said receiver forming an input data matrix with a preamble portion corresponding to said preamble portion of said signals and an information data portion corresponding to said information data portion of said signals;
• a matrix decomposition processor coupled to receive said preamble data portion of said input data matrix and providing a first decomposition matrix and a second decomposition matrix;
• a detector with an input for said first decomposition matrix and using a set of substantially orthogonal preamble vectors to provide a set of detected preamble correlation vectors, wherein said each detected preamble correlation vector corresponds to one of said plurality of remote units;
• a weight vector generator coupled to receive said second decomposition matrix and said detected preamble correlation vectors and providing a set of weight vectors, wherein each of said weight vectors is computed using a corresponding one of said set of detected preamble correlation vectors;
• and
• a despreader coupled to receive said information data portion of said input data matrix and said set of weight vectors and providing a set of despread symbol vectors, wherein each despread symbol vector corresponds to one of said plurality of remote units.

A base station receiver system for recovering a plurality of data streams from a plurality of signals, each signal transmitted from a corresponding one of a plurality of remote units in a radio communication network and each signal having a preamble portion and an information data portion, comprising:

• a receiver coupled to receive said signals, said receiver forming an input data matrix with a preamble portion corresponding to said preamble portion of said signals and an information data portion corresponding to said information data portion of said signals;
• a matrix decomposition processor coupled to receive said preamble portion of said input data matrix and providing a first decomposition matrix and a second decomposition matrix;
• a multiplier using element by element multiplication of a base code vector with said first decomposition matrix and providing a descrambled matrix;
• a detector with an input for said descrambled matrix and using a set of substantially orthogonal preamble vectors to provide a set of detected preamble correlation vectors, wherein said each detected preamble correlation vector corresponds to one of said plurality of remote units;
• a weight vector generator coupled to receive said second decomposition matrix and said detected preamble correlation vectors and providing a set of weight vectors, wherein each of said weight vectors is computed using a corresponding one of said set of detected preamble correlation vectors;
• and
• a despreader coupled to receive said information data portion of said input data matrix and said set of weight vectors and providing a set of despread symbol vectors, wherein each detected despread symbol vector corresponds to one of said plurality of remote units.

A remote unit receiver system for recovering a data stream from a signal transmitted from a base station in a radio communication network, said signal having a preamble portion and an information data portion, comprising:

• a receiver coupled to received said signal, said receiver forming an input data matrix with a preamble portion corresponding to said preamble portion of said signal and an information data portion corresponding to said information data portion of said signal;
• a matrix decomposition processor coupled to receive said preamble portion of said input data matrix and providing a first decomposition matrix and a second decomposition matrix;
• a correlator coupled to receive said first decomposition matrix and providing a correlation vector, wherein said correlation vector is a cross-correlation of said first decomposition matrix and a preamble vector uniquely associated with said remote unit;
• a weight vector generator coupled to receive said second decomposition matrix and said correlation vector and providing a weight vector;
• and
• a despreader coupled to receive said information data portion of said input data matrix and said weight vector and providing a despread symbol vector.

A method for communicating a plurality of data streams from a base unit to a plurality of remote units in a radio communication network, each one of said plurality of data streams being destined for a corresponding one of said plurality of remote units, comprising the steps of:

• converting said plurality of data streams into a plurality of signal vectors, wherein each signal vector comprises a sequence of information symbols and a preamble associated with a corresponding one of said plurality of remote units;
• spreading said plurality of signal vectors using a plurality of base spreading weight vectors to form a composite spread signal, wherein each one of said plurality of base spreading weight vectors is associated with a corresponding one of said plurality of remote units and is applied to the signal vector destined for said corresponding remote unit;
• transmitting said composite spread signal;
• receiving said composite spread signal at each one of said plurality of remote units;
• forming an input data matrix at each remote unit, wherein said input data matrix comprises a preamble portion and an information data portion;
• detecting at each remote unit said associated preamble for said remote unit in said preamble portion;
• and
• applying a remote unit despreading weight vector at each remote unit to said information data portion to reconstruct said sequence of information symbols corresponding to said remote unit.