Abstract
This paper details a new orthogonal-frequency-division-multiplexing (OFDM) modulator based on the use of a pseudorandom postfix (PRP)-OFDM and discusses low-complexity equalization and channel estimation/tracking architectures. The main property of this new modulation scheme is the ability to estimate and track the channel variations semi-blindly using order-one statistics of the received signal. Compared with known cyclic prefix OFDM (CP-OFDM) pilot-symbol-assisted modulation (PSAM) schemes, the pilot overhead is avoided: The channel estimation is performed based on the exploitation of pseudorandomly weighted postfix sequences replacing the guard interval contents of CP-OFDM. PRP-OFDM is shown to be of advantage if the target application requires 1) a minimum pilot overhead, 2) low-complexity channel tracking (e.g., high mobility context), and 3) adjustable receiver complexity/performance trade-offs (available due to the similarities of PRP-OFDM to the zero-padded OFDM (ZP-OFDM) modulation scheme) without requiring any feedback loop to the transmitter.
| Original language | English |
|---|---|
| Pages (from-to) | 1005-1017 |
| Number of pages | 13 |
| Journal | IEEE Transactions on Signal Processing |
| Volume | 54 |
| Issue number | 3 |
| DOIs | |
| Publication status | Published - Mar 2006 |
| Externally published | Yes |
Keywords
- Channel estimation
- Cyclic prefix
- Equalization
- IEEE 802.11a
- Orthogonal frequency-division multiplexing (OFDM)