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Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment, 1990
IEEE Transactions on Communications, 1991
... 39, NO. 5, MAY 1991 713 Performance of Binary and Quaternary Direct-Sequence Spread-Spectrum ... more ... 39, NO. 5, MAY 1991 713 Performance of Binary and Quaternary Direct-Sequence Spread-Spectrum Multiple-Access Systems with Random Signature Sequences Evaggelos Geraniotis, Senior Member, IEEE, and Behzad Ghaffari, Student Member, IEEE ...
IEEE Journal on Selected Areas in Communications, 1990
Two forms of spread-spectrum signaling: direct sequence and hybrid (direct sequence/frequency hop... more Two forms of spread-spectrum signaling: direct sequence and hybrid (direct sequence/frequency hopped) are shown to provide high broadcast capability, especially when used in conjunction with forward-error-control coding schemes. The broadcast capability is defined as the maximum number of simultaneous distinct messages that can be transmitted to distant receivers from a single transmitter at a given bit-error-rate. This quantity provides a useful measure of the capacity of hub-to-mobile or satellite-to-earth-station links of communication networks. When bursty data or voice traffic is dominant in such networks, the above forms of spread-spectrum code-division multiple-access (CDMA) provide a viable alternative to frequency-division (FDMA) or time-division (TDMA) multiple-access. Different ways of multiplexing the direct-sequence and hybrid signals are presented which employ distinct carriers, distinct pairs of orthogonal carriers, and only two orthogonal carriers for broadcasting the different messages. Systems with chip-synchronous signals and systems with random delays between the signals are considered. The average error probability of all systems is evaluated using the characteristic-function and Gaussian-approximation techniques. Besides the uncoded systems, systems using Reed-Solomon and convolutional codes are analyzed. A comparison of the broadcast capability of the different schemes is presented.
Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment, 1990
IEEE Transactions on Communications, 1991
... 39, NO. 5, MAY 1991 713 Performance of Binary and Quaternary Direct-Sequence Spread-Spectrum ... more ... 39, NO. 5, MAY 1991 713 Performance of Binary and Quaternary Direct-Sequence Spread-Spectrum Multiple-Access Systems with Random Signature Sequences Evaggelos Geraniotis, Senior Member, IEEE, and Behzad Ghaffari, Student Member, IEEE ...
IEEE Journal on Selected Areas in Communications, 1990
Two forms of spread-spectrum signaling: direct sequence and hybrid (direct sequence/frequency hop... more Two forms of spread-spectrum signaling: direct sequence and hybrid (direct sequence/frequency hopped) are shown to provide high broadcast capability, especially when used in conjunction with forward-error-control coding schemes. The broadcast capability is defined as the maximum number of simultaneous distinct messages that can be transmitted to distant receivers from a single transmitter at a given bit-error-rate. This quantity provides a useful measure of the capacity of hub-to-mobile or satellite-to-earth-station links of communication networks. When bursty data or voice traffic is dominant in such networks, the above forms of spread-spectrum code-division multiple-access (CDMA) provide a viable alternative to frequency-division (FDMA) or time-division (TDMA) multiple-access. Different ways of multiplexing the direct-sequence and hybrid signals are presented which employ distinct carriers, distinct pairs of orthogonal carriers, and only two orthogonal carriers for broadcasting the different messages. Systems with chip-synchronous signals and systems with random delays between the signals are considered. The average error probability of all systems is evaluated using the characteristic-function and Gaussian-approximation techniques. Besides the uncoded systems, systems using Reed-Solomon and convolutional codes are analyzed. A comparison of the broadcast capability of the different schemes is presented.