12 research outputs found
Application of photonics in next generation telecommunication satellites payloads
Next generation broadband telecommunication satellites are required to provide very high data throughput using complex multibeam architectures. These high throughput 'Terabit/s' Satellites will incorporate payloads with very large quantity of conventional RF equipment, co-axial cables, waveguides, harnesses and ancillary equipment, making the Assembly, Integration and Test (AIT) very complex. Use of 'RF over Fiber' and associated photonics equipment can make the process of AIT much simpler with the added benefit of significant reduction in number of payload equipment and inherent payload mass
Towards demonstration of photonic payload for telecom satellites
To address the challenges of the Digital Agenda for Europe (DAE) and also to remain in line with the evolution of terrestrial communications in a globally connected world, a major increase in telecoms satellites capacity is required in the near future.
With telecom satellites payloads based on traditional RF equipment, increase in capacity and flexibility has always translated into a more or less linear increase in equipment count, mass, power consumption and power dissipation.
The main challenge of next generation of High Throughput Satellites (HTS) is therefore to provide a ten-fold-increased capacity with enhanced flexibility while maintaining the overall satellite within a "launchable" volume and mass envelope [1], [2], [3]. Photonic is a very promising technology to overcome the above challenges. The ability of Photonic to handle high data rates and high frequencies, as well as enabling reduced size, mass, immunity to EMI and ease of harness routing (by using fibre-optic cables) is critical in this scenario
New Generation Cooperative and Cognitive Dual Satellite Systems: Performance Evaluation
Investigating innovative satellite architectures with enhanced system through-
put is one of the most important challenges towards realizing the next generation
of satellite communication systems. In this context, we study two advanced architectures, namely cooperative and cognitive satellite systems. These designs allow the spectral coexistence of two multibeam satellites over a common coverage area with the overlapping beam patterns. In the cooperative dual satellite system, we consider coordination between two coexisting transmitters in order to reduce the intersatellite interference. This is achieved by employing adequate user scheduling, based on the channel state information of each user. To this end, a semi-orthogonal interference aware scheduling algorithm is applied. Further, in the cognitive dual satellite system, we employ a cognitive beamhopping technique assuming that the secondary gateway is aware of the primary's beamhopping pattern. Moreover, we
compare the performances of these schemes with those of the conventional multi-
beam and overlapping dual satellite systems in terms of spectral efficiency, power
efficiency and user fairness. Finally, we provide several insights on the performance
of these schemes and provide interesting future works in these domains
Slot clouds: getting more from orbital slots with networking
The co-located satellites in the orbital slot together form a network and, particularly when using and communicating with the Internet Protocol, can be viewed as a network 'cloud' that provides functionality in a flexible manner