Address Assignment for a Time-Frequency-Coded, Spread-Spectrum System

In multiple-access, spread-spectrum communication, each user has access to the entire system bandwidth.12 One way of distinguishing the signals from different users is to give each user an address consisting of a fixed pattern in time and frequency. The information to be transmitted is modulated or coded onto the address. The receiver detects the appropriate address and decodes the message. This technique is often referred to as random-access discrete address ( r a d a ) or code-division multiple access (cdma). This paper deals with such a system proposed by A. J. Viterbi3 for multiple-access satellite communication by mobile users. It has been 1241 studied for mobile radio communication by D. J. Goodman et al.4 A somewhat similar system, utilizing a different modulation technique, has been proposed by G. R. Cooper and R. W. Nettleton5 and has been investigated by P. S. Henry.6 We consider the problem of generating the addresses assigned to the individual users. By means of an algebraic method, we derive a set of addresses that guarantee minimum interference.