The second Mobile User Objective System (MUOS) satellite built by Lockheed Martin for the U.S. Navy was encapsulated into its payload fairing yesterday. It is scheduled to launch July 19 aboard a United Launch Alliance Atlas V launch vehicle.

The MUOS constellation replaces the legacy Ultra High Frequency (UHF) Follow-On system and delivers secure, prioritized voice and data communications, a first for mobile users who need high-speed mission data on the go.

The first MUOS satellite, launched in 2012, has been providing high quality legacy voice communications for users, and terminals are already testing using the advanced payload that enables data exchanges.

More than 20,000 existing terminals are compatible with and can access the MUOS legacy UHF payload, and with the release of the new waveform developed for increased data-handling capacity, many of these terminals could be retro-fitted to access the Wideband Code Division Multiple Access (WCDMA) payload.

This advanced WCDMA payload incorporates commercial technology designed to provide 16 times the number of accesses as the legacy UHF Follow-On system that it replaces.

The geosynchronous constellation consists of four satellites and one on-orbit spare, which are expected to achieve full operational capability in 2015, extending UHF narrowband communications availability well past 2025.