Low complexity predistortion and equalization in nonlinear multicarrier satellite communications
2015 (English)In: EURASIP Journal on Advances in Signal Processing, ISSN 1687-6172, E-ISSN 1687-6180, Vol. 2015, 30Article in journal (Refereed) Published
Aiming to reduce the power/mass requirements in satellite transponders and toreduce mission costs, joint amplification of multiple-carriers using a singleHigh-Power Amplifier (HPA) is being considered. In this scenario, a carefulinvestigation of the resulting power efficiency is essential as amplification isnonlinear, and multicarrier signals exhibit enlarged peak-to-average power ratio.Thus, operating the amplifier close to saturation vastly increases signal distortionresulting in a severe degradation of performance, especially for higher ordermodulations. This paper proposes a reduced-complexity digital pre-distortion(DPD) scheme at the transmitter and a corresponding equalizer (EQ) at thereceiver to mitigate these nonlinear effects. Scenarios include both the forward aswell as the return links. In particular, the paper exploits the MIMO Volterrarepresentation and builds on a basis pursuit approach using a LASSO (leastabsolute shrinkage and selection operator) algorithm to achieve an effienct basisrepresentation, avoiding large computational complexity, to describe the selectionof pre-distorter/ equalizer model. The work further compares and contrasts thetwo mitigation techniques taking various system aspects into consideration. Thegains, in performance and amplification efficiency, demonstrated by the use ofDPD/ EQ motivate their inclusion in next generation satellite systems.
Place, publisher, year, edition, pages
2015. Vol. 2015, 30
Satellite communications; multicarrier signal; MIMO systems; joint amplification; nonlinear distortions; predistortion DPD; equalization; LASSO
IdentifiersURN: urn:nbn:se:hig:diva-18910DOI: 10.1186/s13634-015-0215-0ISI: 000360573500001ScopusID: 2-s2.0-84925867893OAI: oai:DiVA.org:hig-18910DiVA: diva2:786747