Very high throughput satellites (HTS), where single transponders have large bandwidths (in the order of 500 MHz), significantly reduced the cost per Mbit for satellite communications, and are therefore omnipresent for applications like broadband, mobile and enterprise connectivity. An HTS transponder can amplify single or multiple carriers. Single carrier transmission is still the most efficient mode in a nonlinear channel due its lower peak-to-average power ratio. In order to avoid too complex and expensive receivers, the wide carrier (around 500 MHz) is chopped in time slices such that receivers can decode their part of the very wide carrier. This crosslayer technology, applied for single carrier transmission, may bring overhead in some cases, also leading to some inefficiencies. In this paper, we will introduce and explain timeslicing and present a holistic efficiency comparison between single carrier transmission with timeslicing and multi-carrier transmisson without timeslicing, with and without non-linear predistortion. We conclude that Newtec non-linear predistortion (present in Newtec Equalink) with single or multi-carrier transmission outperforms single carrier transmission without non-linear predistortion. In addition, the throughput gain of single carrier transmission with respect to dual (four) carrier transmission is around 6% (9%) for linearized channels, the nowadays standard. Adding Newtec Equalink on top of single carrier transmission yields a total gain around 15% and 20% over dual and four carrier transmission without non-linear predistortion, respectively.
An efficiency comparison between timeslicing and multi-carrier transmission for linearized transponders, Page 1 of 2
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