On the Capacity of a PPM UWB Multiple-Access System with a Single User Noncoherent Reception
We consider an uncoordinated multiple-access system that employs a modulation technique, in which the probability of suppressing the signal sent by a certain user can be considered negligible, to transmit information via a wireless channel (e.g. time hopping (TH) with pulse position modulation (PPM)).This channel can be considered as an A channel (channel without intensity information) . For this channel a new method of transmission is proposed. The expression for the capacity of a multiple access system employing the proposed transmission method (for the single user reception case) is obtained. Both non-asymptotic and asymptotic formulas are derived and asymptotic behavior of the capacity (for the single user reception case) is studied.