Abstract
Subcarrier and power allocation in orthogonal frequency division multiplexing (OFDM) relaying system has been regarded as a powerful method to improve system performance. A dual-hop OFDM relaying system employing decode-and-forward (DF) relaying protocol is considered and a low-complexity subcarrier and power allocation (PA) scheme with four steps is proposed in this paper. First, the dual-hop subcarriers are matched according to their actual strength, then we allocate the total transmit power between source and relay with respect to their average channel attenuation of first and second hop. Afterwards, we reformulate the original max-min problem into a standard maximization problem and give the optimal PA at relay for a given source PA to maximize the instantaneous rate. Finally, the sum transmit power of each given subcarrier pair is reallocated to further enhance the system capacity. Simulation results show that compared with the uniform power allocation algorithms, the proposed power allocation algorithms can achieve higher system capacity.
| Original language | English |
|---|---|
| Pages (from-to) | 5013-5020 |
| Number of pages | 8 |
| Journal | Journal of Information and Computational Science |
| Volume | 9 |
| Issue number | 16 |
| Publication status | Published - 1 Dec 2012 |
| Externally published | Yes |
Keywords
- Decode-and-forward (DF)
- Power allocation
- Relay
- Subcarrier matching