Power Loading Using Order Mapping in OFDM Systems With Limited Feedback

Author

Choi, Eun H. ; Choi, Wan ; Andrews, Jeffrey G. ; Womack, Baxter F.

Author_Institution

Dept. of Electr. & Comput. Eng., Univ. of Texas at Austin, Austin, TX, USA

Volume

15

fYear

2008

fDate

6/30/1905 12:00:00 AM

Firstpage

545

Lastpage

548

Abstract

This letter proposes an approximate waterfill power loading scheme using limited feedback in orthogonal frequency division multiplexing (OFDM) systems. The proposed technique achieves nearly the capacity of optimal waterfill power loading, while significantly reducing feedback by using order information for the subcarrier channel gains. Furthermore, the proposed power loading technique can circumvent the practical shortcomings of previous limited feedback power loading techniques by simply exploiting order mapping and interpolation. The advantages are particularly visible at low SNR or for many subcarriers, both of which will be very common in emerging wireless broadband OFDM standards.

Keywords

OFDM modulation; channel estimation; feedback; interpolation; OFDM system order mapping; approximate waterfill power loading scheme; channel estimation; feedback; interpolation; orthogonal frequency division multiplexing systems; subcarrier channel gain; wireless broadband OFDM standards; Feedback; Feeds; Frequency estimation; Interpolation; Iterative algorithms; MIMO; OFDM; Quantization; Signal processing algorithms; Transmitters; Channel estimation; feedback compression; order mapping; orthogonal frequency division multiplexing (OFDM);

fLanguage

English

Journal_Title

Signal Processing Letters, IEEE

Publisher

ieee

ISSN

1070-9908

Type

jour

DOI

10.1109/LSP.2008.925755

Filename

4563461