Impact of power spread constraints on a multiuser detection enabled ad hoc network

Multiuser detection (MUD) in a mobile ad-hoc network can significantly improve throughput by exploiting the natural power spreads (PS) between users. Scheduling algorithms can take advantage of the network geometry to enable this increase in throughput by reusing space to allow multiple transmissions at the same time when there is no penalty to the individual links. We show through simulation that MUD power scheduling algorithms can significantly increase network throughput as a function of the number of simultaneous transmissions and MUD algorithm capabilities. Without the need for spreading, a receiver is able to decode multiple transmitted signals when there is a power spread between the signals. Thus with a priori knowledge of scheduling information and received powers, a MUD power scheduling algorithm can efficiently allocate transmission times to increase network throughput at virtually no cost to the individual links. In this paper we motivate the usefulness of MUD without spreading in an ad-hoc network. Next we present the range of acceptable power spreads (both upper and lower limits) that lead to these gains. Additionally, using random node locations we show the likelihood of finding scenarios where scheduling leads to this low cost MUD network gain and show the corresponding network throughput gain.