A UMTS-FDD Cell Search Engine

Abstract

This paper addresses the initial acquisition for the UMTS-FDD W-CDMA standard. It presents an innovative cell searcher design optimized for acquisition speed and low power consumption [1]. The proposed architecture relies on a memory-based digital matched filter with permuted processing order. We can reconfigure the same filtering hardware to process the three steps of the UMTS-FDD initial cell search, due to a thorough HW/SW codesign, in particular the implementation of an innovative algorithm for the second step of the initial acquisition. The searcher can also perform other functions such as initial delay profiling, neighboring cell search and idle-mode timing alignment, which are typically carried out, at least partially, by the Rake receiver. These additional capabilities allow for further system-level power savings because they avoid activating the Rake and reduce the RF front-end working time to a bare minimum.