Running
The PULSARS (Precision Ubiquitous Low-cost Synthetic Aperture Regional Satellite) mission concept utilises a swarm of 16U cube-sats with deployable antenna in a geostationary orbit slot to provide a high capacity and scalable bi-directional 5G Narrow-Band IoT (NB-IOT) service with very high spectrum reuse by exploiting ground-based beamforming technology to dynamically create coherent beams over individual users.
To ensure low-cost infrastructure in-space, the satellites are relatively simple, with all of the system complexity embodied within the ground station infrastructure, which comprises a number of calibration earth stations to undertake continuous orbit determination, with a master gateway providing the signal acquisition and dynamic beam forming, using cloud-RAN architectures for scalability.
The initial system concept incorporates a deployer and 10 satellites to provide 8 million transactions per day for 80,000 user terminals, scaling to 70 satellites per geostationary slot with subsequent launches.
The advantages to PULSARS include:
- The distributed formation of satellite nodes results in very narrow, tight beams of less than 1km diameter coverage on earth. The communications zone is therefore very contained to the User’s position making the service highly secure;
- It is expected that each User could expect data throughput rates that are 10x greater than a conventional single beam system. The concentrated power of the beams permits communication with very small terminals such as handsets, embedded vehicles, IoT sensors and VSATs;
- The modular nature of the multi-satellite formation means the system is scalable;
- The system is also highly robust and redundant. A failure of one satellite does not result in failure of the entire system and the small and cheap satellite costs means that replacements can be launched in short timeframe;
- The system works best in the lower spectrum bands, increases the spectral efficiency enabling growth into new markets.
