To develop a high bandwidth and capacity processor providing flexible channelisation and sub-channel routing between uplink and downlink. An efficient channelisation filter design will maximise spectrum efficiency with low power and mass. There will be the option to include onboard transmit and receive digital beamforming at sub-channel level. The digital processor has baseband interfaces and the associated analogue to digital and digital to analogue converters. It will be suitable for mobile missions, digital audio broadcast and fixed & broadcast satellite service missions.
Digital processors offer dramatic advantages over conventional analogue payloads. This is evidenced by the Inmarsat 4 payloads, developed by Astrium, and operating successfully in orbit. Whilst these advantages are well understood, a primary concern has historically been perceived risk and the high price to achieve these goals.
The NGP product provides a generic solution to a very wide range of mission opportunities. The technical risk is therefore minimised for flight programmes, and a reliable delivery schedule can be achieved.
Costs are also minimised for two reasons:
The result is a product which can be used equally for fixed services through to mobile services at an affordable price.
The key benefits are:
The main features are:
The product development plan is divided into two distinct phases, each of approximately 12 months. The first phase includes the development of the key subassemblies including ASIC and power supply development. The conclusion is the equipment CDR. The 2nd phase carries out assembly and integration testing.
Under subcontract to Astrium GmbH, a central control unit is being developed in the same timescale as the main digital processor.
The plan is augmented by additional funding to headstart Inmarsat XL activities. This includes work to enhance the industrialisation of the product not only at the DSP level, but also at the Systems and pre/post processor stages.