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StatusOngoing
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Status date2011-11-22
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:
- A generic product is developed, needing minimal customisation for each operator / spacecraft bus,
- The unique NGP architecture which allows the processor to be scaled to the payload requirements.
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:
- A generic product applicable to a wide range of missions,
- Scalable solutions from small/piggy back missions to fully processed payload missions with multi-feed antennas,
- Modular to allow flexible payload integration and test to minimise cost / risk,
- Allow operator to re-configure payload to meet evolving traffic / services during mission lifetime,
- High bandwidth / flexible switching offers operator maximum utilisation of payload capacity and bandwidth efficiency,
- Improved spectral efficiency compared to analogue solutions,
- Link budget advantage due to onboard ALC at sub-channel level,
- Antenna coverage can be adapted to traffic requirements (by digital beamforming),
- Onboard spectral monitoring,
- Low power and mass implementation based on latest space qualified technologies,
- High reliability design with built-in redundancy,
- Efficient thermal & mechanical design for ease of platform accommodation.
The main features are:
- Analogue baseband inputs and outputs at first Nyquist frequencies for simple interfacing with payload up- and down-converters,
- Modular design offering scalability for different mission sizes,
- Up to 14 input / output ports per module,
- Port bandwidth up to 320MHz,
- Contiguous channelisation with minimum sub-channel width <200kHz to meet variable bandwidth requirement,
- Fully flexible switching from any input port to any output port, and any input frequency to output frequency,
- Supports uni-cast, multi-cast and broadcast traffic routing,
- Fixed / automatic level control and power monitoring,
- Digital beamforming option to form transmit and receive sub-channel signals based on multiple feed antenna,
- Standard spacecraft serial bus or SpaceWire control interfaces,
- Innovative algorithm and architectural design,
- Optional high speed telecommand/telemetry link capable,
- High efficiency low volume power supply.
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.
- Preliminary DSP and controller ASIC designs nearing completion,
- Change note agreed to expand programme to include industrialisation activities to support Inmarsat XL,
- DSP analysis and system modelling complete,
- Power Supply requirements fully agreed,
- Main boards under development.