AEHF-1 Milsat may launch next week

According to an article on SpaceFlight now, the AEHF-1 Milsat is scheduled to launch next week, August 12, and will be tested at an on orbit geo location of 90 degrees west.

The advanced satellite that will be used for relying secure US military communications will be launched on an Atlas 5 (5-531 configuration) rocket from Cape Canaveral AS, Florida. Liftoff had been targeted for August 12 at 7:14 a.m. EDT, but the launch could be sliding a day or two.

This maiden AEHF bird should be ready, if all goes well, to enter service early next year from an orbital location dictated by the needs at that time, officials said.

"AEHF will provide tactical and strategic support to a wide variety of Army, Navy, Marine and Air Force users," said Col. Michael Sarchet, commander of the Protected Satellite Communications Group at the Space and Missile Systems Center.

The U.S. military purchased a series of AEHF satellites for launches in the coming years to replace the aging Milstar communications spacecraft that link the national leadership and warfighters. The Advanced EHF Program is the next generation of global, highly secure, survivable communications system within all services of the Department of Defense.

"AEHF is a very sophisticated satellite because it is built to provide the highest levels of protection for our nation's most critical users. Encryption, low probability of intercept and detection, jammer resistance and the ability to penetrate the electro-magnetic interference caused by nuclear weapons are essential features when communication can be of the highest priority," Sarchet said.

In Nov. 2001, the U.S. Air Force awarded Lockheed Martin Space Systems and Northrop Grumman Space Technology (Formerly TRW Space & Electronics) a $2.698 billion contract to begin the System Development and Demonstration (SDD) phase of the Advanced Extremely High Frequency (Advanced EHF) Program.

The SDD phase will deploy two Advance EHF satellites and the Advance EHF mission control segment. The new mission control segment will support both Milstar and AEHF. Lockheed Martin will serve as the developer of the ground segment, satellite bus provider, space vehicle integrator and overall systems integrator and prime contractor. This role builds on Lockheed Martin's successful experience on Milstar and DSCS. Northrop Grumman will provide the payload and associated components (digital processor and RF equipment).

The MILSATCOM Program Office, located at the Space and Missile Systems Center, Los Angeles Air Force Base, Calif., is the Advanced EHF contract manager and lead agency for ensuring the secure communications capabilities of this system are made available to the warfighter.

The Advanced EHF Program is the follow-on to the DoD's Milstar highly secure communication satellite program, which currently has a four-satellite operational constellation. The last Milstar satellite was successfully launched in April 2003.

As envisioned by the Pentagon, the fully operational Advanced EHF constellation will consist of four crosslinked satellites providing coverage of the Earth from 65 degrees north latitude to 65 degrees south. These satellites will provide more data throughput capability and coverage flexibility to regional and global military operations than ever before. A fifth satellite built could be used as a spare or launched to provide additional capability to the envisioned constellation.

Advanced EHF satellites will provide 10 times greater total capacity and offer channel data rates six times higher than that of Milstar II communications satellites. The higher data rates permit transmission of tactical military communications such as real-time video, battlefield maps and targeting data.

To accomplish this, Advanced EHF adds new higher data rate modes to the low data rate and medium data rate modes of Milstar II satellites. The higher data rate modes will provide data rates up to 8.2 million bits of data per second (Mbps) to future Advanced EHF Army terminals. That rate is more than 150 times faster than the 56 kilobit-per-second modems of today's personal computers. Each Advanced EHF satellite employs more than 50 communications channels via multiple, simultaneous downlinks. For global communications, the Advanced EHF system uses inter-satellite crosslinks, eliminating the need to route messages via terrestrial systems.



U.S. Air Force Fact Sheet
Advanced Extremely High Frequency (AEHF) System

Mission/Vision

The Advanced Extremely High Frequency (AEHF) System is a joint service satellite communications system that will provide survivable, global, secure, protected, and jam-resistant communications for high-priority military ground, sea and air assets. Advanced EHF will allow the National Security Council and Unified Combatant Commanders to control their tactical and strategic forces at all levels of conflict through general nuclear war and supports the attainment of information superiority.

Background

The AEHF System is the follow-on to the Milstar system, augmenting and improving on the capabilities of Milstar, and expanding the MILSATCOM architecture. AEHF will provide connectivity across the spectrum of mission areas, including land, air and naval warfare; special operations; strategic nuclear operations; strategic defense; theater missile defense; and space operations and intelligence.

Features

Part of the MCSW's Protected SATCOM Group, the system consists of four satellites in geosynchronous earth orbit (GEO) that provides 10 times the throughput of the 1990s-era Milstar satellites with a substantial increase in coverage for users. First launch in late 2010, AEHF will provide continuous 24-hour coverage between 65 degrees north and 65 degrees south latitude. The AEHF system is composed of three segments: space (the satellites), ground (mission control and associated communications links) and terminals (the users). The segments will provide communications in a specified set of data rates from 75 bps to approximately 8 Mbps. The space segment consists of a cross-linked constellation of three satellites. The mission control segment controls satellites on orbit, monitors satellite health and provides communications system planning and monitoring. This segment is highly survivable, with both fixed and mobile control stations. System uplinks and crosslinks will operate in the extremely high frequency (EHF) range and downlinks in the super high frequency (SHF) range. The terminal segment includes fixed and ground mobile terminals, ship and submarine terminals, and airborne terminals used by all of the Services and international partners (Canada, Netherlands and UK). MCSW is responsible for acquisition of the space and ground segments as well as the Air Force terminal segments. The Army and Navy will acquire their own terminals.

General Characteristics

Primary Function: Near-worldwide, secure, survivable satellite communications
Primary Contractor: Lockheed Martin Space Systems Company
Payload: Onboard signal processing, crossbanded EHF/SHF communications
Antennas: 2 SHF Downlink Phased Arrays, 2 Crosslinks, 2 Uplink/Downlink Nulling Antennas, 1 Uplink EHF Phased Array, 6 Uplink/Downlink Gimbaled Dish Antenna, 1 Each Uplink/downlink earth coverage horns
Capability: Data rates from 75 bps to approximately 8 Mbps

New satellite model showcased in dedication ceremony

by Tech. Sgt. Kimberley Harrison, Air Force Space Command Public Affairs



Gen. C. Robert Kehler, commander of Air Force Space Command, addresses attendees at a special ceremony at Peterson Air Force Base, Colo., where he accepted a one-quarter scale model of the new Advanced Extremely High Frequency satellite from Lockheed Martin representatives. The first AEHF satellite is scheduled to be launched the last quarter of 2010. (U.S. Air Force photo/Tech. Sgt. Matt Lohr)

Air Force Space Command officials, in partnership with Lockheed Martin representatives, unveiled a one-quarter scale model of the Advanced Extremely High Frequency satellite here at Peterson April 1 during a ceremony in the AFSPC headquarters building.

"It is phenomenally important to us and the warfighting team to get these satellites on orbit and what we have here today is a good start," said Gen. C. Robert Kehler, AFSPC commander.

The AEHF system is a follow-on to the Milstar Satellite Communications system, augmenting and improving on the capabilities of Milstar, and expanding the Military Satellite Communications architecture to enable transformational communications and network-centric warfare.

"This is important ... this is a great first step and I appreciate all the hard work to get the model to us and to donate it to us," said General Kehler.

The AEHF satellite will provide communications connectivity across the spectrum of mission areas including land, air and naval warfare; special operations; strategic nuclear operations; strategic defense; theater missile defense; and space operations and intelligence.

"We are delighted to provide this satellite model to our customers at Peterson Air Force Base," said Mr. Kevin Bilger, vice president and general manager of Global Communications Systems at Lockheed Martin. "Our partnership with the U.S. Air Force on the Advanced EHF program is a source of genuine pride for our company."

The AEHF system will provide global, secure, survivable satellite communications allowing the National Security Council members and unified combatant commanders to control their tactical and strategic forces at all levels of conflict and support the attainment of information superiority.

"We are on the right pathway with Advanced EHF #1," said General Kehler. "There are very few satellite capabilities that are directly related to presidential guidance ... two of those are constant global coverage missile warning and protected communications ... that's how important this is. Nothing else that we do has that level of attention in terms of the specific requirements we are meeting, so this is a big deal to bring AEHF #1 to orbit."

The first AEHF satellite is currently scheduled to launch during the last quarter of 2010.

"Celebration will begin next year when we are able to watch this go to orbit successfully and then we turn it over for warfighting use and help our strategic users from the president all the way down to the tactical users make the best use of this new capability. I'm looking forward to those days," exclaimed General Kehler.

Once on orbit, the AEHF satellite will provide the warfighter a ten-fold increase in communications capability over Milstar.

"We look forward to fielding this protected Advanced EHF communications capability and contributing to your ongoing mission success," said Mr. Bilger.

"With Lockheed Martin in the lead, Northrup Grumman as their close partner, with the great team of United Launch Alliance and what they're going to deliver for us in terms of a launch vehicle and a ride to orbit, with the team on the ground that supports all of this and with the operational team that eventually accepts this new satellite for operational use and warfighting application ... we will succeed," stated General Kehler.

"I appreciate this team," he said. "The country appreciates this team. The country is reliant on this team to bring this satellite to fruition, to get it through the rest of its testing envelope and to put it on orbit."

Northrop Grumman Integrates Antennas On Flight Payload

From Hilary courtesy of MT editor Rachel Baughn.

Northrop Grumman Integrates Phased Array Antennas On Advanced EHF Flight Payload

The uplink and downlink phased array antennas developed by Northrop Grumman Corporation for its first advanced extremely high frequency (EHF) military satellite communications payload have been integrated onto the first flight structure, and their performance has been verified alongside other essential payload components. Delivery of the payload to Lockheed Martin, the prime contractor for the Advanced EHF program, remains on track.

Using phased array antennas, advanced microelectronics, extremely high data rate (XDR) waveforms and efficient protocols, Advanced EHF will deliver an increase in capacity and connectivity over the legacy Milstar system.

"The performance verification of our phased array antennas on the flight structure is a key achievement in the integration and test of the first Advanced EHF flight payload," said Gabe Watson, vice president of the Advanced EHF payload program for Northrop Grumman's Space Technology sector. "Successful development and production of the AEHF phased array antennas are essential to our ability to deliver higher capacity, highly secure communications to the U.S. military."

The phased array antennas Northrop Grumman has developed for Advanced EHF are directly applicable to the next-generation transformational satellite communications system (TSAT), which will ultimately replace the Milstar and Advanced EHF programs. The company is teamed with Lockheed Martin in the competition to build TSAT, and this accomplishment also represents a reduction in risk and cost to the TSAT program, Watson noted.

More than 40 separate tests were run on the Advanced EHF payload's three phased array antennas, consisting of one uplink antenna and two downlink antennas, as they were integrated successfully into the payload. These were part of the 231 tests of the Advanced EHF Flight 1 payload test suite.

The antennas also completed an additional series of tests which verify the operation of each individual antenna element. The phased array antennas will be the first of their kind to operate at 20 GHz and 40 GHz in space.

Test results verified that the performance of all three antennas exceed gain and coverage requirements and that they successfully interfaced with all applicable components in the payload, including critical digital processing and the RF subsystems.