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. 1, no 1, 1-15 p.Article in journal (Refereed) Published
Aiming to reduce the power/mass requirements in satellite transponders and to reduce mission costs, joint amplification of multiple-carriers using a single High-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 distortion resulting in a severe degradation of performance, especially for higher order modulations. 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 as well as the return links. In particular, the paper exploits the MIMO Volterra representation and builds on a basis pursuit approach using a LASSO (least absolute shrinkage and selection operator) algorithm to achieve an effienct basis representation, avoiding large computational complexity, to describe the selection of pre-distorter/ equalizer model. The work further compares and contrasts the two mitigation techniques taking various system aspects into consideration. The gains, in performance and amplification efficiency, demonstrated by the use of DPD/ EQ motivate their inclusion in next generation satellite systems.
Place, publisher, year, edition, pages
2015. Vol. 1, no 1, 1-15 p.
Satellite communications; multicarrier signal; MIMO systems; joint amplification; nonlinear distortions; predistortion DPD; equalization; LASSO.
Signal Processing Telecommunications
Research subject Electrical Engineering
IdentifiersURN: urn:nbn:se:kth:diva-159545DOI: 10.1186/s13634-015-0215-0ISI: 000360573500001ScopusID: 2-s2.0-84925867893OAI: oai:DiVA.org:kth-159545DiVA: diva2:786755
QC 201505262015-02-062015-02-032015-09-18Bibliographically approved