When was gps invented

The Global Positioning System GPS is a positioning, navigation and timing service based on a constellation of satellites which are owned by the U. Reserved only for military use upon its inception, GPS is now available to everyone, and has been for some time. Due to its widespread use, GPS technology is now well incorporated into our daily lives. Used in your car to navigate traffic or by your smartphone to offer more accurate and customized web search results, GPS is a technology we have become so comfortable with, we often take it for granted.

In total, there are at least 24 operational satellites in the GPS constellation, with additional satellites in reserve that can be activated when needed. As of May , GPS. The satellites circle the Earth two times a day at 20, km 12, miles up. The U. What started off as a method of studying the Earth from space quickly grew into a universal technology utilized by nearly every country in the world.

One of the major milestones was the ending of Selective Availability SA in , which allowed civilians access to more precise GPS readings and opened the door to new technology advancements. The first portable GPS receiver developed for consumers was made by electronic navigation company Magellan. The inaugural device, the NAV , weighed in at 1. At the time, the high cost of satellite navigation meant that outside the military, only freight, delivery and select other companies could afford to use systems.

These days, portable GPS tracking is much more affordable. For example, GPS is essential to fleet management , especially for tracking vehicle location and driving behavior with telematics , as well as routing and dispatching. As the capabilities of technology continue to expand, one can only imagine what GPS technology will look like in the future. Using physical maps or asking strangers for directions is now a thing of the past. New navigation systems will power businesses and government services around the world.

The U. Navy experimented with a satellite navigation system for its submarines in the mids. The Transit System used six satellites in circumpolar orbits, calculating the Doppler shift of radio signals to ascertain position.

Testing began the following year, and the first operational GPS satellite was launched in It became clear in that the initially planned 18 satellites would not provide sufficient coverage , so the number was increased to 24 including three substitutes. The system was intended for military uses like targeting missiles, as well as peacekeeping uses like monitoring nuclear-bomb tests outlawed by the Nuclear Test Ban Treaty.

But, after Korean Airlines Flight wandered into Soviet territory in and was shot down with a loss of lives, even the military thought there might be distinct advantages to sharing the GPS system with civilians. After further testing for military use, the U. Air Force Space Command declared " full operational capability " on April 27, This apparently occurred because the satellite used a two-axis gravity gradient stabilization system that does not function well at these altitudes.

NTS-1 carried other space technology demonstrations including highly efficient solar cells. The vehicle included two modified cesium beam oscillators developed by Frequency and Time Systems Inc.

FTS of Danvers Massachusetts. The key atomic clock developer was the engineer and creative entrepreneur Robert Kern. This clock showed great initial promise but it was not yet a space prototype in terms of radiation hardening and parts life. It could then have supplemented the satellites being developed by Rockwell, providing another passive ranging signal for the user equipment tests at Yuma Proving Ground. As a result of these failures, the cesium clock tests were inconclusive.

Beard, p. For the next step, NRL defined a radiation-hardening program and contracted with FTS to develop a hardened cesium clock. Unfortunately, the clock suffered a premature failure of the power supply after only 12 hours of operation. FTS soon found the root cause and fixed the design. Beginning with NDS 5, the on-board cesium clocks performed well and were equal or better in stability to the Rockwell rubidium oscillators. By , a few Pentagon authorities had recognized that a new satellite-based navigation system would be a valuable asset with multiple military applications.

Literally hundreds of positioning and navigation systems in use by the DoD were expensive to maintain and upgrade. Obviously, a single replacement system offered significant cost savings. Unfortunately, the two competing concepts from B and NRL apparently confused the decision-makers.

Discussions grew very acrimonious at times. As a result of this inter-service competition and a reluctance to commit the necessary monies, the Pentagon put off making any decision. In November of , Col. Bill Dunn , who led the advance planning group XR , identified Parkinson as a potential candidate to head the floundering B program. Parkinson had a very relevant background in navigation, guidance, and control that included a Ph. He had been chair of the Astronautics Department at the U.

Air Force Academy, spent three years as a guidance analyst at the Central Inertial Guidance Test Facility, and was operationally oriented with 26 combat missions in AC gunships. The background was a match, but Parkinson expressed an unwillingness to volunteer for the assignment if he were not assured that he would be the program director. Schultz said he could not yet make that promise. However, immediately after Parkinson left his office, the general reassigned him to the B program and effectively made him the director.

Beginning in December, immediately after he assumed control of B, Parkinson instituted a series of 7 a. At these gatherings, the program staff reexamined every aspect of the proposed B program, including alternatives.

This educational process was a key to having everyone in the Program Office completely understand the technical issues they faced. During this period Gen. Schultz supported the program in every way that he could.

In particular, Parkinson was allowed to recruit Air Force officers whose background and experience were aligned with the needs of the fledgling program. All had advanced engineering degrees from the very best universities in the country including MIT, Michigan, and Stanford. In addition, virtually every officer had experience in developing real hardware or in testing inertial guidance systems. In addition there was a small, carefully-selected group of Aerospace technical support personnel led by Walt Melton from to This fine group of Aerospace engineers and scientists was experienced in an all technical aspects of space navigation programs and particularly skilled at issues relating to signal modulation, satellite position prediction, and building long-life satellites.

Many of their names will be highlighted in Part Two of this story. The Aerospace contingent continued to enjoy the strong support of the president of the Aerospace Corporation, Ivan Getting.

Malcolm Currie , formerly of Hughes Aircraft, who had just been appointed to the number three position in the DoD, found himself flying between Washington, D. His secondary purpose was to oversee the relocation of his family, but he needed an official reason to travel to Los Angeles. After a few weeks, his host Gen. Schultz ran out of subjects to present, and instead invited Currie to spend an afternoon with his new program director, Col.

This informal meeting was held in private, in a very small cubicle within the JPO offices. With a Ph. After that meeting, Currie became a good friend to and a sponsor of the new satellite-based navigation program.

DSARC 1. It was held at the Pentagon, and attended by senior officers of all services, with Mal Currie presiding. Currie immediately invited Parkinson into his private office to tell him he wanted a new system proposal developed that would incorporate the best features of all the technical alternatives.

He emphasized the need for a joint program involving all services. Lonely Halls Meeting. Parkinson immediately called a meeting in the Pentagon over Labor Day weekend, September The light at end of those tunnels, both figuratively and literally, came from a small conference room on the top floor, seating about a dozen attendees, all Air Force officers except for three Aerospace Corporation engineers.

Parkinson wanted the isolation to ensure unfettered creativity in defining the new proposal. Leading to this, the Analytical Sciences Corporation TASC under the guidance of Gaylord Green had completed a new systems study, a review and update of the earlier systems study directed by Jim Woodford and Hideyoshi Nakamura for project B in — Dual Use. One aspect should be strongly pointed out. Civilian users were to be given free access to the signal specification and were expected to use the so-called clear acquisition signal for navigation and other purposes.

In fact, Parkinson highlighted civilian use when he testified before Congress on the proposed new system. GPS Approval.

That Labor Day weekend of September had been a very busy three days. Over the next two-and-a-half months there was a flurry of activity as Parkinson made presentations and defended the concept before all those who could block the proposal in the Pentagon. This effort was culminated with the approval to proceed on December 14, There were no significant modifications to the proposal that had been developed during the Lonely Halls meeting in the Pentagon.

During the whole Phase I development, Parkinson resolved to avoid any conflict with the other original competitors to build a satellite-based navigation system. He deliberately ignored dubious claims of invention and statements regarding the origins of GPS technology. Until quite recently, he has overlooked these false claims by those who did not directly participate in determining the GPS architecture and did not participate in the specific GPS design and deployment.

He felt the real purpose was to build the system, not to fight over credit. Recently an article appeared that implied that the GPS design was essentially the same as Timation. Essentially, they are the same system. Aware that this incorrect statement denigrated the people who had first analyzed, advocated, and demonstrated the fundamental concept, as well as built the system, Parkinson resolved to correct the record, and highlight the names of those who deserve credit. This is a major purpose of this article.

This article has been reviewed and approved for veracity by virtually all the key figures still alive who actually designed, built, and tested GPS. End of Part One. Watch for Part Two in our June issue. From left, Major Mel Birnbaum made many important contributions. He was famous for marathon code reviews that could last 18 hours straight. He hated to miss schedules! Don Henderson later Maj. Ken Juvette, director of procurement; and Lt.

Joe Strada, a key leader in the extensive test program. If you enjoyed this article, subscribe to GPS World to receive more articles just like it. Your behavior appears to be a little unusual. Please verify that you are not a bot. Follow Us. Part 1 of a Two-Part Story. Read Part 2 here. Cover: GPS World.