Ultra-wideband signal acquisition with hybrid DS-TH spreading

The usage of long spreading sequences and the fine timing resolution result in a large search space during acquisition in ultra-wideband (UWB) systems. This paper presents a two-stage signal acquisition scheme for UWB systems employing a hybrid signaling format involving direct sequence (DS) spreading and time hopping (TH), which significantly reduces the search space. The resulting acquisition system consists of two stages, one each for the acquisition of the TH and DS sequences. The dense multipath channel typical of UWB systems implies that there can exist more than one phase to which the receiver can lock on and achieve satisfactory demodulation performance subsequent to acquisition. We define the set of such phases as the hit set. The hybrid signaling format coupled with the multi-phase hit set help significantly improve the acquisition performance of the UWB system. The performance of the proposed acquisition system, measured in terms of the mean detection time, is evaluated analytically and supported by computer simulation

[1]  R.A. Scholtz,et al.  Rapid acquisition of ultra-wideband signals in the dense multipath channel , 2002, 2002 IEEE Conference on Ultra Wideband Systems and Technologies (IEEE Cat. No.02EX580).

[2]  Liuqing Yang,et al.  Non-data aided timing acquisition of ultra-wideband transmissions using cyclostationarity , 2003, 2003 IEEE International Conference on Acoustics, Speech, and Signal Processing, 2003. Proceedings. (ICASSP '03)..

[3]  Moe Z. Win,et al.  The ultra-wide bandwidth indoor channel: from statistical model to simulations , 2002, IEEE J. Sel. Areas Commun..

[4]  Mohamed-Slim Alouini,et al.  Digital Communication Over Fading Channels: A Unified Approach to Performance Analysis , 2000 .

[5]  Georgios B. Giannakis,et al.  Ultra-wideband communications: an idea whose time has come , 2004, IEEE Signal Processing Magazine.

[6]  Edgar H. Callaway,et al.  Home networking with IEEE 802.15.4: a developing standard for low-rate wireless personal area networks , 2002, IEEE Commun. Mag..

[7]  Andreas F. Molisch,et al.  Channel models for ultrawideband personal area networks , 2003, IEEE Wireless Communications.

[8]  Tan F. Wong,et al.  On the asymptotic performance of threshold-based acquisition systems in multipath fading channels , 2004, Information Theory Workshop.

[9]  Moe Z. Win,et al.  Ultra-wide bandwidth time-hopping spread-spectrum impulse radio for wireless multiple-access communications , 2000, IEEE Trans. Commun..

[10]  Moe Z. Win,et al.  Performance of low-complexity RAKE reception in a realistic UWB channel , 2002, 2002 IEEE International Conference on Communications. Conference Proceedings. ICC 2002 (Cat. No.02CH37333).

[11]  Tan F. Wong,et al.  A search strategy for ultra-wideband signal acquisition , 2005, IEEE Transactions on Communications.

[12]  Aarne Mämmelä,et al.  Bit error probability of a matched filter in a Rayleigh fading multipath channel in the presence of interpath and intersymbol interference , 1999, IEEE Trans. Commun..

[13]  Andreas F. Molisch,et al.  A rapid acquisition technique for impulse radio , 2003, 2003 IEEE Pacific Rim Conference on Communications Computers and Signal Processing (PACRIM 2003) (Cat. No.03CH37490).

[14]  Liuqing Yang,et al.  Symbol timing estimation in ultra wideband communications , 2002, Conference Record of the Thirty-Sixth Asilomar Conference on Signals, Systems and Computers, 2002..

[15]  Moe Z. Win,et al.  On the energy capture of ultrawide bandwidth signals in dense multipath environments , 1998, IEEE Communications Letters.

[16]  Tan F. Wong,et al.  On equal-gain combining for acquisition of time-hopping ultra-wideband signals , 2006, IEEE Transactions on Communications.

[17]  Roger L. Peterson,et al.  Introduction to Spread Spectrum Communications , 1995 .

[18]  Zhi Tian,et al.  Efficient timing acquisition in dense multipath for UWB communications , 2003, 2003 IEEE 58th Vehicular Technology Conference. VTC 2003-Fall (IEEE Cat. No.03CH37484).

[19]  S. Pasupathy,et al.  Acquisition performance of an ultra wide-band communications system over a multiple-access fading channel , 2002, 2002 IEEE Conference on Ultra Wideband Systems and Technologies (IEEE Cat. No.02EX580).

[20]  Srikrishna Bhashyam,et al.  Time-selective signaling and reception for communication over multipath fading channels , 2000, IEEE Trans. Commun..

[21]  K. Siwiak,et al.  Ultra-wide band radio: introducing a new technology , 2001, IEEE VTS 53rd Vehicular Technology Conference, Spring 2001. Proceedings (Cat. No.01CH37202).

[22]  Andreas Polydoros,et al.  A Unified Approach to Serial Search Spread-Spectrum Code Acquisition - Part I: General Theory , 1984, IEEE Transactions on Communications.

[23]  Moe Z. Win,et al.  Impulse radio: how it works , 1998, IEEE Communications Letters.