Crest factor reduction of an OFDM/WiMAX network

摘要

African countries lag behind the rest of the world in their use of Information and Communication Technologies (ICTs). To reduce the digital divide quickly and cost-effectively, wireless networks are considered. WiMAX (Worldwide Interoperability for Microwave Access) is a wireless broadband access technology that uses Orthogonal Frequency Division Multiplexing (OFDM) which is a multicarrier modulation scheme. OFDM presents a problem of a high crest factor or Peak to Average Power Ratio (PAPR). To circumvent this problem either High Power Amplifiers (HPAs) with large dynamic range or PAPR reduction techniques are used. The former scheme increases cost of the system while the latter introduces redundancy or distortion. A novel PAPR reduction scheme is presented. It is a combination of the ideas of Tone Reservation and Selected Mapping. The advantage of this scheme is that it has a lower complexity. It is simulated for a WiMAX system.