Assessing the impact of physical layer techniques on ad hoc network performance

This article provides an overview on the topic of ad hoc network performance analysis, mainly from a physical layer standpoint. The emphasis of the paper is on how the individual link and network performance can be evaluated in an analytically tractable manner, such that design insights can be obtained and optimization over key parameters is possible. Our model is that of a large random network, where the wireless channel comprises path-loss and fading. Various physical layer factors are taken into account: the multiple-access (MA) scheme, such as direct-sequence (DS) CDMA and frequency-hopping (FH) CDMA; error correction coding such as Reed–Solomon (RS) or convolutional coding; coherent or noncoherent detection; the use of multiple-input, multiple-output (MIMO) techniques to enhance error protection or to increase the transmission rate. The performance of the network is evaluated and optimized in terms of useful metrics such as the network throughput, the information efficiency and the transmission capacity.