22 research outputs found
On the Delay-Throughput Tradeoff in Distributed Wireless Networks
This paper deals with the delay-throughput analysis of a single-hop wireless
network with transmitter/receiver pairs. All channels are assumed to be
block Rayleigh fading with shadowing, described by parameters
, where denotes the probability of shadowing and
represents the average cross-link gains. The analysis relies on the
distributed on-off power allocation strategy (i.e., links with a direct channel
gain above a certain threshold transmit at full power and the rest remain
silent) for the deterministic and stochastic packet arrival processes. It is
also assumed that each transmitter has a buffer size of one packet and dropping
occurs once a packet arrives in the buffer while the previous packet has not
been served. In the first part of the paper, we define a new notion of
performance in the network, called effective throughput, which captures the
effect of arrival process in the network throughput, and maximize it for
different cases of packet arrival process. It is proved that the effective
throughput of the network asymptotically scales as , with , regardless of
the packet arrival process. In the second part of the paper, we present the
delay characteristics of the underlying network in terms of the packet dropping
probability. We derive the sufficient conditions in the asymptotic case of such that the packet dropping probability tend to zero, while
achieving the maximum effective throughput of the network. Finally, we study
the trade-off between the effective throughput, delay, and packet dropping
probability of the network for different packet arrival processes.Comment: Submitted to IEEE Transactions on Information Theory (34 pages
Energy, latency and capacity Trade-offs in wireless multi-hop networks
International audienceThis paper concentrates on characterizing energy, latency and capacity trade-offs in multi-hop wireless ad-hoc networks. Therefore, a multiobjective framework is proposed to derive the Pareto-optimal set of solutions with respect to these three criteria. The work presented in this paper assumes a linear network where transmission powers and relay positions are optimization variables. We study the asymptotic state where the distance between source and destination is very high such that the number of hops tends to infinite. Two types of traffic are considered in the following. First, low rate traffic is analyzed by characterizing the multiobjective performance of a single packet transmission using an interference free multi-hop relaying strategy. Second, a continuous flow of packets from a unique source is considered. In the first case, we show an important theorem which states that all Pareto optimal solutions with respect to delay and energy metrics provide the same target SNR at the receiver side. In the second case, our analytical results highlight how the energy/delay Pareto front moves when considering a capacity constraint and the optimal re-use factor is derived