Time spread modulation system for land mobile radio communications

A novel time spread modulation (TSM) scheme which uses the time diversity effect is presented. Several modifications are proposed to the standard TSM scheme to allow it to be used in land mobile radio communications. Quadrature amplitude modulation with fading compensation is applied to increase the spectral efficiency. Symbol interleave and maximum likelihood estimation are applied to improve TSM performance under Rayleigh fading conditions. Computer simulation shows that the proposed TSM scheme can provide a large process gain in land mobile radio communications.<<ETX>>

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