Optimal chip waveforms for DS-CDMA with generalized OQPSK modulation

The effect of chip waveform shaping on both the error and spectral performance of DS-CDMA communication systems using generalized offset quadrature modulation formats is investigated. A solution to the problem of optimizing the chip waveform shape to achieve minimum multiple access interference variance at a given in-band power bandwidth occupation and with a continuous phase constraint is presented. Several design examples with various bandwidth occupancies are used to illustrate the gains achieved by the optimized chip waveforms over other conventional modulation schemes such as OQPSK and MSK.

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