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Symbol spreading for ultrawideband systems based on multiband OFDM

Ramachandran, I; Nakache, Y P; Orlik, P; Zhang, J and Molisch, Andreas LU (2004) IEEE International Symposium on Personal, Indoor and Mobile Radio Communications, 2004 In 15th IEEE International Symposium on Personal, Indoor and Mobile Radio Communications, PIMRC 2004. 2. p.1204-1209
Abstract
We investigate the effect of symbol spreading on the performance of ultrawideband systems based on multiband OFDM. Ultrawideband channels offer the possibility of very high frequency diversity, as the used bandwidth is much larger than the coherence bandwidth of the channel. In multiband-OFDM, frequency diversity stems from (i) forward error correction coding, which distributes the symbols associated with one bit among different tones, and (ii) interleaving, which distributes the symbols among different employed frequency bands. We show that for weak (rate 3/4) error correcting codes, the achieved diversity order is insufficient. However, the use of Walsh-Hadamard spreading gives additional diversity within each frequency band and greatly... (More)
We investigate the effect of symbol spreading on the performance of ultrawideband systems based on multiband OFDM. Ultrawideband channels offer the possibility of very high frequency diversity, as the used bandwidth is much larger than the coherence bandwidth of the channel. In multiband-OFDM, frequency diversity stems from (i) forward error correction coding, which distributes the symbols associated with one bit among different tones, and (ii) interleaving, which distributes the symbols among different employed frequency bands. We show that for weak (rate 3/4) error correcting codes, the achieved diversity order is insufficient. However, the use of Walsh-Hadamard spreading gives additional diversity within each frequency band and greatly improves the performance. Furthermore, we propose a novel scheme for grouping OFDM tones before the spreading is performed. This grouping gives additional flexibility in the system design. (Less)
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author
organization
publishing date
type
Chapter in Book/Report/Conference proceeding
publication status
published
subject
keywords
diversity reception, error correction codes, forward error correction, telecommunication channels, ultra wideband communication, OFDM modulation
in
15th IEEE International Symposium on Personal, Indoor and Mobile Radio Communications, PIMRC 2004.
volume
2
pages
1204 - 1209
conference name
IEEE International Symposium on Personal, Indoor and Mobile Radio Communications, 2004
external identifiers
  • Scopus:11244275591
ISBN
0-7803-8523-3
language
English
LU publication?
yes
id
14cf0377-997b-4afc-9015-6772050e8f7e (old id 600761)
alternative location
http://ieeexplore.ieee.org/iel5/9435/29981/01373889.pdf?tp=&isnumber=&arnumber=1373889
date added to LUP
2007-12-06 10:25:41
date last changed
2017-01-01 08:19:35
@inproceedings{14cf0377-997b-4afc-9015-6772050e8f7e,
  abstract     = {We investigate the effect of symbol spreading on the performance of ultrawideband systems based on multiband OFDM. Ultrawideband channels offer the possibility of very high frequency diversity, as the used bandwidth is much larger than the coherence bandwidth of the channel. In multiband-OFDM, frequency diversity stems from (i) forward error correction coding, which distributes the symbols associated with one bit among different tones, and (ii) interleaving, which distributes the symbols among different employed frequency bands. We show that for weak (rate 3/4) error correcting codes, the achieved diversity order is insufficient. However, the use of Walsh-Hadamard spreading gives additional diversity within each frequency band and greatly improves the performance. Furthermore, we propose a novel scheme for grouping OFDM tones before the spreading is performed. This grouping gives additional flexibility in the system design.},
  author       = {Ramachandran, I and Nakache, Y P and Orlik, P and Zhang, J and Molisch, Andreas},
  booktitle    = {15th IEEE International Symposium on Personal, Indoor and Mobile Radio Communications, PIMRC 2004.},
  isbn         = {0-7803-8523-3},
  keyword      = {diversity reception,error correction codes,forward error correction,telecommunication channels,ultra wideband communication,OFDM modulation},
  language     = {eng},
  pages        = {1204--1209},
  title        = {Symbol spreading for ultrawideband systems based on multiband OFDM},
  volume       = {2},
  year         = {2004},
}