The envelope elimination and restoration (EE&R) transmitter inherently provides high-power efficiency for linear amplification, but it suffers out-of-band spectral re-growth from a number of distortion sources such as differential time delay between envelope and phase paths and nonlinear conversion and feed-through effect due to envelope variation of the radio frequency (RF) power amplifier. The combination of EE&R and predistortion techniques is discussed, which are used to compensate for the nonlinear distortions, and a modified RF phase signal is used to reduce the feed-through effect for an IEEE802.11g application. This results in an EE&R transmitter with a performance of −37 dBc at the first adjacent channel power ratio (ACPR) and −47 dBc at the second ACPR and an average power added efficiency of 47.3%.
|Translated title of the contribution||Combining envelope elimination and restoration and predistortion techniques for use in IEEE802.11g systems|
|Pages (from-to)||832 - 838|
|Number of pages||7|
|Journal||IET Microwaves, Antennas and Propagation|
|Publication status||Published - Aug 2007|
Bibliographical notePublisher: Institution of Engineering and Technology (IET)
Rose publication type: Journal article
Sponsorship: The work reported in this paper is part of the Wireless Enablers area of the Core 3 Research Programme of the Virtual Centre of Excellence in Mobile & Personal Communications. Mobile VCE, www.mobilevce.com, whose funding support including that of EPSRC, is gratefully acknowledged.