Mobile frequency-hopping CDMA systems

Through analysis and simulation, a unified evaluation of the potential performance of both mobile peer-to-peer and sectorized cellular frequency-hopping code-division multiple-access (CDMA) systems is presented. The equivalent number of frequency channels and the minimum area-mean signal-to-noise ratio are defined and shown to be important parameters in understanding and predicting network capacity. The effects of spectral splatter are analyzed. Separated orthogonality is defined and shown to be useful in completely eliminating intracell or intrasector interference. Spatial diversity by postdetection rather than predetection combining is proposed and shown to be invaluable. Noncoherent demodulation by a frequency discriminator rather than parallel matched filters and envelope detectors is proposed and shown to be effective. It is shown that even without exploiting either its natural bandwidth advantage or power control, frequency-hopping CDMA provides a reverse-link capacity nearly the same as direct-sequence CDMA with realistic power-control imperfections.