To provide the capacity required for Australian Sky Muster users, 101 spot beams are used to illuminate small population centres.
This technique increases the capacity of Sky Muster considerably over earlier satellite systems that provided internet in Australia.
SkyMuster Earth Station Gateways
There are nine active Sky Muster Earth Station Gateways, geographically spread across Australia.
They are located in areas that are least likely to suffer from atmospheric degradation and each site is connected by redundant fibre cable to Sydney.
All traffic from the Earth Station Gateways is aggregated by nbn at Eastern Creek in Sydney where the various Sky Muster providers interconnect.
This chart identifies the connection between a spot beam and the Earth Station Gateway.
Compiled by BIRRR ©
How are spot beams allocated?
nbn use a clever beam planning tool that determines from the customers coordinate location, which satellite and to which spot beam that location is best allocated. It also advises the antenna size and the power of the TRIA (transmit and receive integrated assembly). For some locations there is a choice of up to 10 x different beam/ satellite combinations. A user might be allocated to one beam on one satellite and a week later their neighbour might be allocated to a different beam, or a different satellite, or different equipment; for effectively the same latitude and longitude.
If a spot beam were to ‘fill up’ (e.g. higher take up rates in some areas versus others compared to initial predictions) the system could flag a problem and propose to move existing services from one beam to another. This would require a 10 minute planned outage per service moved.
You can estimate what spot beam you are on by using the map above and ‘guess’ the beam you are on and then visit here and click on the spot beam you maybe on. Then you can zoom in on the map and it shows you what area that spot beam covers. More than one spot beam can cover certain areas, so it is not a certainty that your are on one spot beam. Here is an example of one area covered by 3 spot beams.
Why some customers have slightly lower latency than others
When conducting Ookla speed test you may notice that some SkyMuster users record a lower latency or ping than others.
This difference in ping times is due to the differing distances of the terrestrial paths to Sydney. The time taken for a signal to travel the terrestrial path, adds delay to the relatively fixed satellite propagation delay, which is approximately 590ms for Sky Muster.
Geraldton in WA is much further from Sydney than say Broken Hill NSW and there may be up to 30ms difference in ping times, as a consequence.
Images courtesy of the Satbeams website. Satbeams.com is a global Web 2.0 reference website that provides consolidated information about the Geostationary/Communications satellites, their technical details, coverage zones and frequency charts.