Dynamic Resource Management in High Throughput Satellite with Multi Port Amplifier (MPA)

Satellite Communication Overview

Satellites have been providing services such as television broadcast, broadband internet, cellular backhaul, and intelligence gathering for many years. Communication satellites have traditionally been built with continental-scale wide beams. Wide beams have an advantage because of the large area they can cover - as much as 42% of the earth’s surface from a single satellite geostationary orbit. However, low Equivalent Isotropically Radiated Power (EIRP) and Gain to Noise Temperature (G/T) are inherent in such wide beams and require larger terminal antennas to maintain the link and provide acceptable data rates. Applications of these satellites have been expanding in mobility including both commercial and government aviation and maritime vessels – all constrained in antenna size.

High Throughput Satellites (HTS)

The satellite industry has acknowledged the growth in demand and started adopting HTS architecture that has large numbers of small spot beams, reuse frequency across beams, and offer higher EIRP and G/T. Frequency reuse allows much more bandwidth to be supported within the same coverage area as wide beams. For example, Ku-band has frequency assigned for earth-to-space from 14.0 GHz to 14.5 GHz – a total 500 MHz band. A wide beam covering the size of a continent can deliver, in both vertical and horizontal polarization, capacity limited by a bandwidth of 2x500 MHz. An HTS with n beams and u-color reuse, and available bandwidth B, in both polarizations can deliver capacity with an effective bandwidth of:

An HTS with 16 beams in a coverage area and 4-color reuse pattern can increase the available bandwidth by 4 fold relative to a wide beam satellite covering the same area. Mobility applications, constrained in terminal antenna size and challenged to operate in wide beam satellites, can offer service with a higher data rates with HTSs. An example of an HTS with 4-color reuse is shown in Figure 1.

Figure 1.

HTS with four-color frequency reuse spot beams