Random-access techniques for communication networks with spread-spectrum signaling

This report briefly summarizes progress made during the past year. The emphasis is on results which are applicable to the Navy's proposed intratask-force (ITF) communication network. One goal of our research was to study basic random access strategies. An important feature was to consider buffered stations and to allow the packet arrival rates at the different stations to independently fluctuate. The rate fluctuation leads to more bursty traffic than the usual Poisson or Bernoulli arrival models. Much to our surprise, even for rather bursty models the time division multiple access (TDMA) strategy produces delays which are not much larger than the ideal (but unrealizable) perfect scheduling strategy. As a result, we shifted more attention to considering how a network wide TDMA strategy might be implemented using spread-spectrum signaling. We sought a strategy which incorporates the multiple-access capability of spread-spectrum signaling. The result is a procedure controlling multiple access interference in a scheduled spread-spectrum network. The procedure is compatible with existing link activation scheduling algorithms which are not designed to control such interference.