Performance of Pre-Rake diversity combining in UWB-IR communications

Ultra-wideband impulse-radio has some advantages for indoor high speed wireless communication such as high multipath tolerability and low power consumption. Rake diversity combining is one of the most effective techniques for improving the signal to noise ratio. The improvement depends on the number of correlation detectors (Rake fingers) in receiver. Therefore, it is considered to be difficult to employ the technique for terminal because of hardware complexity and power efficiency. In contrast, Pre-Rake diversity combining is recently attracted considerable attention because it offers the Rake combining without the Rake fingers in receiver (terminal-side). Thus, the system complexity at the terminal will be significantly reduced. In this paper the performances of Pre-Rake diversity combining gain are experimentally investigated where two types of Pre-Rake diversity combining methods are compared. The measurements were conducted in online, inside a typical office environment.