Power Backoff Reduction Techniques for Generalized Multicarrier Waveforms
1 Department of Systems and Computer Engineering, Carleton University, Ottawa, Canada, K1S 5B6
2 Institute of Electronics and Telecommunications, Poznań University of Technology, Poznań 60965, Poland
EURASIP Journal on Wireless Communications and Networking 2008, 2008:437801 doi:10.1155/2008/437801Published: 21 November 2007
Amplification of generalized multicarrier (GMC) signals by high-power amplifiers (HPAs) before transmission can result in undesirable out-of-band spectral components, necessitating power backoff, and low HPA efficiency. We evaluate variations of several peak-to-average power ratio (PAPR) reduction and HPA linearization techniques which were previously proposed for OFDM signals. Our main emphasis is on their applicability to the more general class of GMC signals, including serial modulation and DFT-precoded OFDM. Required power backoff is shown to depend on the type of signal transmitted, the specific HPA nonlinearity characteristic, and the spectrum mask which is imposed to limit adjacent channel interference. PAPR reduction and HPA linearization techniques are shown to be very effective when combined.