GPS technology not just for military, also benefits civilian users

Published Sept. 8, 2006
By LaTonya Lofton-Collins
Global Positioning Systems Wing

LOS ANGELES AFB, CA -- You're stranded in the middle of Los Angeles. You can't get to where you need to be. You pull out your cell phone or log onto the navigation system in your car and voila ... instant directions to your destination!

Since first launched in 1978, the Navstar Global Positioning System has been available for civilian application worldwide. There has been impressive growth in civil use, in surveying, construction, precision agriculture and geologic research of the size and shape of the earth.

GPS is not only critical for the warfighter but also to the international, civil and commercial communities in conducting day-to-day business within our global economy. GPS is used in many of today's modern conveniences such as banking systems, ATM machines, cell phones, pagers and satellite radio. It can also assist in locating lost animals and stolen cars.

GPS provides the highest quality of service to meet constantly evolving user requirements such as automobiles equipped with navigation systems which provide accurate directions to any mapped location; in the air providing safe and efficient aviation; on oceans and navigable waterways providing more efficient use of maritime resources; railroad safety; and emergency and rescue services.

"When we started GPS in the seventies, the civil and commercial community had no interest, it was all military," said Col. Rick Reaser, former Global Positioning Systems Wing deputy system program director. "Today, approximately 95 percent of GPS customers are civil or commercial users. The Air Force is very keen on making sure customers' needs are met. Everyone not only knows what GPS is, it's a part of everything they do."

To ensure continued global services, the next generation of GPS satellites will not only provide enhanced capabilities to U.S. Allied military operations but also to civil and commercial users around the globe.

"Sustainment of the GPS constellation is essential, as is modernization of the current and future systems and capabilities," said Col. Allan Ballenger, Global Positioning Systems Wing commander.

One of the major modernization upgrades was the Legacy Accuracy Improvement Initiative, which added additional monitoring stations to improve the reliability of GPS navigation messages. According to GPS program of- ficials, this means every satellite will be observed simultaneously by at least two GPS monitoring stations providing GPS users with greater assurance in system performance. The GPS signal in space accuracy performance was increased by 10-15 percent.

Another was the launch of the first modernized satellite GPS Block IIR-14 (M), which introduced a new military code (M-Code) signal and a new civil signal (L2C). The M-Code signal provides the warfighter with a more robust jam-resistant signal, enabling effective munitions targeting in stressed environments. The L2C signal provides dual-frequency capability to all equipped civil users, allowing correction of ionospheric transmission errors, which improves resistance to interference and increases accuracy.

Shortly after the IIR-M satellites have been launched, the next Block of satellites to be added to the GPS constellation will be the Block IIF satellite. The Block IIF satellite will have the capabilities of Block IIR and IIR-M satellite and will add a third civil signal. The other capabilities will be a faster processor with more memory, and an extended design life of 12 years.

Soon to follow behind the Block IIF satellites will be the Block III which is envisioned to be purchased in incremental capability blocks. The Block III satellites will have the same capabilities of the previous Block IIR and Block IIF satellites with the addition of a fourth civil signal. The fourth civil signal will be interoperable with Europe's Galileo and Japan's Quasi-Zenith Satellite System. The subsequent Blocks will add crosslinks and other features, said a program official.

"Ultimately, it's all about how we continuously improve service for the military and civilian users around the world," said Colonel Ballenger.

Global Positioning System satellites

Navstar Global Positioning System