Northrop Grumman has demonstrated technology for the Advanced Extremely High Frequency (EHF) payload that will greatly improve warfighters’ access to military satellite communications while increasing the range of missions the system can support on the ground, at sea and in the air. The company will provide the Advanced EHF payload to Lockheed Martin, prime contractor for the Advanced EHF system.


Northrop Grumman’s Space Technology sector has completed electrical testing of the uplink phased array antenna, which receives signals from ground terminals. One of the new technologies developed for the Advanced EHF payload, the antenna directs radio frequency beams electronically rather than by moving reflectors mechanically. This allows one array to do the job of many reflectors, giving the flexibility to point-on-demand in fractions of a second, greatly improving warfighter access. It is also the first phased array for space application that operates at 44 GHz. Another new technology is the use of an advanced semiconductor material, indium phosphide (InP), for some of the antenna’s more than 10,000 monolithic microwave integrated circuits. InP ensures excellent low noise, or clear signal, performance.

“With these successful electrical tests, we have shown that electronic beam steering can support a wider range of missions with fewer antennas,” said Clayton Kau, Northrop Grumman Space Technology vice president and manager of the Advanced EHF payload program. “The tests also demonstrate that we are on track to deliver the first flight payload in April 2006.” With the more compact phased array, the Advanced EHF system can process greater amounts of information. It will deliver 10 times greater total capacity and channel data rates six times higher than that of Milstar II communication satellites. Advanced EHF is the successor to the Milstar system. The highly directional antenna additionally reduces the possibility of jamming and intercept by enemies, assuring secure, reliable communications between command and control units wherever they operate.

Lockheed Martin Space Systems, Sunnyvale, CA, is currently under contract to provide the first two Advanced EHF satellites and command and control system. In April, Lockheed Martin successfully completed the system critical design review phase of the program on schedule and is now into the production phase. The MILSATCOM Joint Program Office, located at the Space and Missile Center, Los Angeles Air Force Base, CA, is the contract manager and lead agency for the Advanced EHF program.