Theoretical limits on time delay estimation for ultra-wideband cognitive radios

Creative Commons License

Gezici S., Celebi H., ARSLAN H., Poor H. V.

2008 IEEE International Conference on Ultra-Wideband, ICUWB 2008, Hannover, Almanya, 10 - 12 Eylül 2008, cilt.2, ss.177-180 identifier identifier

  • Yayın Türü: Bildiri / Tam Metin Bildiri
  • Cilt numarası: 2
  • Doi Numarası: 10.1109/icuwb.2008.4653380
  • Basıldığı Şehir: Hannover
  • Basıldığı Ülke: Almanya
  • Sayfa Sayıları: ss.177-180
  • Anahtar Kelimeler: Ultra-wideband (UWB) cognitive radio, time delay estimation, Cramer-Rao lower bound (CRLB), carrier frequency offset (CFO), dispersed spectrum utilization
  • İstanbul Medipol Üniversitesi Adresli: Evet

Özet

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. © 2008 IEEE.