On the multiple-access capacity of multitone-CDMA communications

This paper derives a bit-error-probability expression for an asynchronous multitone-code-division multiple access (CDMA) system and shows that the multiple-access (MA) capacity of this system is identical to that of a conventional (single-carrier) direct-sequence spread-spectrum system under conditions of equal bandwidth and equal bit rate. It is also shown that using more subcarriers to increase the processing gain does not increase the MA capacity.