Emmanuel Lance

A novel dimensioning method for high throughput satellite design

This work describes a novel methodology for the dimensioning of a Ka-Band high throughput satellite (HTS) for broadband communications. The method is based on the optimization of performance for a forward link, as a function of a set of input criteria and a given envelope of available power. This approach is based on a spacecraft architecture using a multi-beam coverage implementing frequency re-use. Among the input criteria, we use the percentage of covered service area with a certain type of earth stations, the service availability and the cost and mass of the system. The proposed methodology is adaptable to any kind of service area. A digital video broadcasting satellite second generation (DVB-S2) air interface with adaptive coding and modulation (ACM) is used as a reference. The method, employing iterative advanced link budget calculations including carrier-to-interference at antenna level, provides the highest capacity given a batch of antenna and pragmatic feed design.

Statistical characterization of the interference on the return link of a broadband satellite system

This work describes an interference study of the return link (user terminals to gateways) of a high throughput satellite (HTS) for broadband services. The aim is to identify a statistical behavior of the inter-spot interferences due to frequency re-use so as to estimate the carrier over interference ratio (C/I) on the uplink segment of the return link for a multi frequency time division multiple access (MF-TDMA) technique. The characterization of the interference will be done based on a mathematical model and validated through empirical observations for different transmission scenarios and satellite systems. In this work, we use the C/I performance at satellite antenna level as a benchmark parameter, in order to find the most faithful statistical law for the generated interferences. The satellite architecture itself uses a multi-beam coverage implementing frequency re-use and spatial separation.