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Method and apparatus for generating orthogonally encoded communication signals for communication system subscribers using multiple orthogonal functions for each orthogonal communication channel. Digital data symbols for signal recipients are M-ary modulated using at least two n-length orthogonal mod

Method and apparatus for generating orthogonally encoded communication signals for communication system subscribers using multiple orthogonal functions for each orthogonal communication channel. Digital data symbols for signal recipients are M-ary modulated using at least two n-length orthogonal modulation symbols, which are generally Walsh functions normally used within the communication system. These symbols are provided by a modulation symbol selector (124) typically from one or more code generators (126, 128), and the modulation is such that M equals a product of a total number of orthogonal functions and the number used to generate individual modulation symbols. Each group of log M encoded data symbols from data processing elements (100, 102) are mapped into one modulation symbol using the modulation symbol selection element (124) according to their binary values. In some embodiments, a fast Hadamard transformer is used for symbol mapping. The resulting communication signals are demodulated by correlating them with the preselected number of orthogonal functions, in parallel, and demodulating the results into M energy values representing each orthogonal modulation symbol. The energy values are mapped into energy metric data using a dual maximum metric generation process. The correlation and demodulation can be accomplished using at least two sets of N correlators (142), N being the number of functions used, and applying correlated signals to one demodulator for each set of correlators (144). Each demodulator outputs M energy values representing each of the M mutually orthogonal modulation symbols, which are then combined into a single set of M energy values. In further configurations, coherent demodulators (172, 174) can be used to produce amplitude values for received signals which are then combined (178) with dual maximum metric results (170) to produce composite metric values for data symbols (178).

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A spread spectrum communication system, comprising: a plurality of gateway type base stations each including at least one communication signal transmitter that transmits signals comprising data symbols to active system users, comprising: a plurality of function generating means each for providing at

A spread spectrum communication system, comprising: a plurality of gateway type base stations each including at least one communication signal transmitter that transmits signals comprising data symbols to active system users, comprising: a plurality of function generating means each for providing at least one of a plurality of orthogonal functions of a plurality of orthogonal functions of length n having a predefined recursive relationship among each other; means for selecting N of said orthogonal functions for each active system user, N being a power of 2; means for forming M mutually orthogonal modulation symbols of length Ln, for each active system user using said N selected orthogonal functions and respective inverses thereof, where M is the product of L and N; means for mapping data symbols into said modulation symbols for each active system user, connected to receive data symbols and orthogonal modulation symbols for each active system user, and for selecting one of said modulation symbols according to binary values for every log M data symbols; a plurality of spreading means each connected to said means for mapping for receiving modulation symbols for respective users and for producing a spread spectrum data signal; and combination means for combining modulation symbols for substantially all active users receiving signals over a common carrier frequency into a communication signal; a plurality of mobile communication units, each including a mobile receiver, comprising: means for selecting and receiving a spread spectrum communication signal from at least one gateway; and demodulation means connected to the means for selecting and receiving, for providing modulation symbols for respective users by demodulating the received spread spectrum communication signal.