AbstractThe continuing need for increased traffic capacity for telephony over satellite links combined with the availability of low cost and accurate LSI compander chips has caused renewed interest in SSB satellite transmission using companders to reduce the impairments caused by thermal noise, interference and intermodulation encountered on the transmission link. This type of transmission is designated as CSSB/AM and may be operated in a multicarrier per transponder (FDMA) manner. The capacity achieved is a function of the average power during the occurrence of speech and because this value has decreased in modern telephone systems, the advantages to be gained from CSSB/AM are increased.This paper presents the development of expressions for channel capacity of CSSB/AM links as a function of carrier‐to‐noise ratio and speech power level while active. These are used to estimate the capacity achievable in an INTELSAT IV type transpon