Technology

In Space

ORBCOMM satellites are relatively small in size, weighing less than one hundred pounds and measuring only forty-two inches in diameter and six inches in height before deployment. Their compact profile is a result of the fact that they do not require a propulsion system to maintain the appropriate orbit, and they have significantly lower power requirements, giving them more reliable travel patterns and a longer functional lifecycle than geostationary satellites.

Each satellite is equipped with a VHF and Ultra High Frequency, or UHF, communication payload capable of operation in the 137.0-150.05 MHz and the 400.075-400.125 MHz bands. The use of the system uplink (Earth-to-space) spectrum is managed by an on-board computer that employs the ORBCOMM-pioneered Dynamic Channel Activity Assignment System, or DCAAS. DCAAS continuously scans the authorized spectrum, identifies frequencies already in use and dynamically assigns your uplink channel to minimize interference. DCAAS changes the uplink frequency at least every 15 seconds, which allows our system to coexist with the current users of the VHF frequency band, and limits interference.

The gateway earth stations and the subscriber communicators communicate with the satellites in the same VHF band, thus reducing complexity, size, power and cost of supporting multiple communications on a single satellite – reductions that are reflected in our affordable subscription rates.