초록 ▼

A system and method for communicating information signals using spread spectrum communication techniques. PN sequences are constructed that provide orthogonality between the users so that mutual interference will be reduced, allowing higher capacity and better link performance. With orthogonal PN co

A system and method for communicating information signals using spread spectrum communication techniques. PN sequences are constructed that provide orthogonality between the users so that mutual interference will be reduced, allowing higher capacity and better link performance. With orthogonal PN codes, the cross-correlation is zero over a predetermined time interval, resulting in no interference between the orthogonal codes, provided only that the code time frames are time aligned with each other. In an exemplary embodiment, signals are communicated between a cell-site and mobile units using direct sequence spread spectrum communication signals. In the cell-to-mobile link, pilot, sync, paging and voice channels are defined. Information communicated on the cell-to-mobile link channels are, in general, encoded, interleaved, bi-phase shift key (BPSK) modulated with orthogonal covering of each BPSK symbol along with quadrature phase shift key (QPSK) spreading of the covered symbols. In the mobile-to-cell link, access and voice channels are defined. Information communicated on the mobile-to-cell link channels are, in general, encoded, interleaved, orthogonal signaling along with QPSK spreading.

대표청구항 ▼

[ We claim:] [1.] An apparatus for transmitting a plurality of data signals in a spread spectrum communication system, comprising:a plurality of signal generator means for providing a plurality of function signals, each function signal being generated according to a respective function of a pluralit

[ We claim:] [1.] An apparatus for transmitting a plurality of data signals in a spread spectrum communication system, comprising:a plurality of signal generator means for providing a plurality of function signals, each function signal being generated according to a respective function of a plurality of orthogonal functions, wherein the plurality of signal generator means comprises: outer signal generator for generating an outer function signal;multiple inner signal generators for generating a plurality of inner function signals each inner function signal being generated according to a respective function of said plurality of orthogonal functions;a plurality of spreading means, each spreading means connected to a respective signal generator means and receiving a respective data signal of the plurality of data signals for producing a respective spread spectrum data signal in response to the respective data signal and a respective function signal, wherein each spreading means includes two exclusive-OR gates:a first exclusive-OR gate having two inputs and one output, a first input connected to a respective inner signal generator and a second input receiving a respective data signal of the plurality of data signals; anda second exclusive-OR gate having two inputs and an output, a first input connected to the outer signal generator, a second input connected to the output of the first exclusive-OR gate, and the output connected to a combining means;a pilot signal generator means for generating a pilot signal according to a function which is orthogonal to each function of the plurality of orthogonal functions;said combining means being connected to the plurality of spreading means, wherein said combining means combines a plurality of spread spectrum data signals into a combined spread spectrum data signal; anda transmit means connected to the combining means for amplifying and transmitting the combined spread spectrum data signal.