"... The overall system architecture of a North American Advanced Satcom system is GEO satellite system in the Ka band, utilizing onboard processing and multiple spot beams to support a large number of residential and small business users with small terminals.
The overall target population based on multimedia market forecast and user loading factors is about 5 million subscribers for a two satellite system.
To support this number of subscribers, each satellite is sized to handle a capacity of 5 Gbps and will reuse the 500MHz RF spectrum a maximum of about sixteen times.
This overall capacity represents about 400 000 users simultaneously, at the estimated average rate per user based on multimedia traffic models..."