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arXiv · 0906.3988

Theoretical Limits on Time Delay Estimation for Ultra-Wideband Cognitive Radios

Sinan Gezici·Hasari Celebi·Huseyin Arslan·H. Vincent Poor
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Abstract

In this paper, theoretical limits on time delay estimation are studied for ultra-wideband (UWB) cognitive radio systems. For a generic UWB spectrum with dispersed bands, the Cramer-Rao lower bound (CRLB) is derived for unknown channel coefficients and carrier-frequency offsets (CFOs). Then, the effects of unknown channel coefficients and CFOs are investigated for linearly and non-linearly modulated training signals by obtaining specific CRLB expressions. It is shown that for linear modulations with a constant envelope, the effects of the unknown parameters can be mitigated. Finally, numerical results, which support the theoretical analysis, are presented.

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Sinan Gezici, Hasari Celebi, Huseyin Arslan, H. Vincent Poor. 2009-06-22. Theoretical Limits on Time Delay Estimation for Ultra-Wideband Cognitive Radios. https://doi.org/10.1109/icuwb.2008.4653380

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