Ultra-wideband (UWB) technology for indoor wireless communications promises high data rates with low-complexity transceivers. Rapid timing synchronization constitutes a major challenge in realizing these promises. In this paper, we establish a novel synchronization criterion that we term "timing with dirty templates" (TDT), based on which we develop and test timing algorithms in both data-aided (DA) and nondata-aided modes. For the DA mode, we design a training pattern, which turns out to not only speed up synchronization, but also enable timing in a multiuser environment. Based on simple integrate-and-dump operations over the symbol duration, our TDT algorithms remain operational in practical UWB settings. They are also readily applicable to narrowband systems when intersymbol interference is avoided. Simulations confirm performance improvement of TDT relative to existing alternatives in terms of mean square error and bit-error rate.
Bibliographical noteFunding Information:
Paper approved by S. N. Batalama, the Editor for Spread Spectrum and Estimation of the IEEE Communications Society. Manuscript received June 11, 2004; revised February 20, 2005 and May 11, 2005. This work was prepared through collaborative participation in the Communications and Networks Consortium sponsored by the U.S. Army Research Laboratory under the Collaborative Technology Alliance Program, Cooperative Agreement DAAD19-01-2-0011, and was supported in part by the National Science Foundation under Grant EIA-0324864. This paper was presented in part at the GLOBECOM Conference, San Francisco, CA, December 2003, and in part at the International Conference on Acoustics, Speech, and Signal Processing, Montreal, QC, Canada, May 2004. The U.S. Government is authorized to reproduce and distribute reprints for Government purposes notwithstanding any copyright notation thereon.
- Direct sequence (DS)
- Estimation and detection
- Time-hopping (TH)
- Timing acquisition
- Ultra-wideband (UWB)