Ranging Mechanism, Preamble Generation, and Performance with IEEE 802.15.4a Low-Rate Low-Power UWB Systems

IEEE 802.15.4a task group is defining an ultra low power consumption and low cost radio for wireless personal area networks (WPANs) applications using ultra-wideband (UWB) technology with high precision ranging capability. Ternary preamble sequences of two different lengths have been proposed and adopted in the IEEE 802.15.4a specification for ranging. In order for a IEEE 802.15.4a low cost UWB device to support multiple frequency bands across the available spectrum and ranging features, as many as twenty-four ternary sequences is required. A sizeable amount of memory is needed to store the codes. In this paper, we propose a method to generate the ternary codes using linear feedback shift registers (LFSRs) as and when it is required, resulting in significant memory savings. The ranging performance using the proposed ternary preamble sequence is evaluated through simulation