Abstract
In this letter, pilot design and channel estimation are discussed for orthogonal frequency-division multiplexing (OFDM) systems with guard subcarriers. First, we investigate the effects of guard band on channel estimation errors. From this, we propose pilot placement having a maximum distance between adjacent pilots except for the guard band, and show that it achieves minimum channel estimation errors among partially equispaced pilots using equivalence of the Toeplitz and circulant matrices. Also, an efficient channel estimator is developed by introducing an extended channel and its finite impulse response (FIR) approximation to overcome high numerical complexity caused by the presence of guard subcarriers and the use of a large number of subcarriers. Simulation results are presented for OFDM and orthogonal frequency division multiple access (OFDMA) systems consistent with IEEE 802.16a standards.
Original language | English (US) |
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Pages (from-to) | 1459-1465 |
Number of pages | 7 |
Journal | IEEE Transactions on Communications |
Volume | 55 |
Issue number | 8 |
DOIs | |
State | Published - Aug 2007 |
Keywords
- Channel estimation
- Orthogonal frequency division multiple access (OFDMA)
- Orthogonal frequency-division multiplexing (OFDM)
- Pilot design
ASJC Scopus subject areas
- Electrical and Electronic Engineering