A Unified Treatment of Optimum Pilot Overhead in Multipath Fading Channels

Abstract--The optimization of the pilot overhead in singleuser wireless fading channels is investigated, and the dependence of this overhead on various system parameters of interest (e.g., fading rate, signal-to-noise ratio) is quantified. The achievable pilot-based spectral efficiency is expanded with respect to the fading rate about the no-fading point, which leads to an accurate order expansion for the pilot overhead. This expansion identifies that the pilot overhead, as well as the spectral efficiency penalty with respect to a reference system with genie-aided CSI (channel state information) at the receiver, depend on the square root of the normalized Doppler frequency. It is also shown that the widely-used block fading model is a special case of more accurate continuous fading models in terms of the achievable pilotbased spectral efficiency. Furthermore, it is established that the overhead optimization for multiantenna systems is effectively the same as for single-antenna systems ...

• Type: Journal
• Year: 2010
• Where: TCOM
• Authors: N. Jindal, A. Lozano
• Keywords: Normalized Doppler Frequency, Software Engineering, Spectral Efficiency, TCOM 2010, Wireless Fading Channels