Iridium Communications has received a contract from the US Department of Defense (DoD) to provide unlimited satellite services from its low Earth orbit (LEO) communications constellation of 66 cross-linked satellites.

The seven-year, $738.5m contract was awarded to support the US Air Force Space Command’s (AFSpC) Enhanced Mobile Satellite Services (EMSS) programme.

The contract will provide DoD and associated subscribers with access to global voice, broadcast, and other services, including netted or Distributed Tactical Communications System (DTCS).

Iridium won a five-year EMSS contract in 2013 to provide satellite airtime services for DoD.

The company has highlighted that a 145% rise was witnessed in the number of DoD subscribers over the course of the five-year contract. The number now stands at 125,000.

Iridium Communications government programmes executive vice-president Scott Scheimreif said: “Iridium’s EMSS contract serves as a model for how commercial operators can cost-effectively and efficiently deliver critical satellite managed services to the warfighter.

“When you combine our unique network, our ecosystem of dedicated partners and an innovative, fixed-price, seven-year contract, you create an optimal environment for DoD and other USG programme offices to effectively plan for and budget their programmes, taking full advantage of the Iridium capability.”

The company has been supporting the EMSS programme for the past 20 years.

It worked with the US Air Force to support efforts to improve information sharing and network situational awareness.

Iridium CEO Matt Desch said: “While this new contract will see continued adoption of Iridium, it will also drive ongoing innovation through collaboration between the US Government, Iridium, industry partners and user communities.”

Desch stated that the company has invested significantly in the network.

The $3bn Iridium NEXT programme involved the launch of 66 LEO satellites, six in-orbit spares and nine ground spares.

Commercial satellite communications play a major role in meeting the DoD’s satellite communication needs.