An ATM/CDMA-based satellite access scheme

This paper presents a new access scheme for an ATM-based satellite communication network. The up-link channel is shared by all users in the system. Access to the up-link channel is done using a direct sequence (DS) code division multiple access (CDMA) technique combined with quadrature phase shift keying (QPSK) modulation to reduce the spectral bandwidth. It is shown that by using forward error control (FEC) the probability of bit error, which is directly affected by the number of users that simultaneously transmit on the up-link channel, can be dramatically reduced. The probability of bit error, the cell success probability and the network efficiency are computed and plotted vs. the number of simultaneous users.