| The technology behind GPS systems can be | | | | information on the GPS satellite itself so there is |
| complicated. However, a little research into what | | | | never a question of whether the satellite is |
| the various systems are and how they work can | | | | working to its greatest potential or not. |
| make choosing the right GPS system an easier | | | | There are around 25 different ground stations, |
| decision. If you have looked into purchasing a GPS | | | | which WAAS uses as reference in the United |
| or owned a GPS system before then you | | | | States alone. The GPS satellite data is |
| probably have seen the term WAAS either on | | | | communicated to these ground stations so the |
| packaging or in ads for GPS systems. | | | | information can be monitored. Then the |
| WAAS stands for Wide Area Augmentation | | | | information is compiled and sent to two master |
| System. WAAS is an intricate GPS technology, | | | | stations (one on the east coast and one of the |
| which was developed to provide locations that are | | | | west coast), which correct any errors in the GPS |
| more accurate. This is done through GPS signal | | | | satellite information. |
| corrections attained through a network of ground | | | | Corrections are made based on the orbit of the |
| stations and satellites. The stations and the | | | | satellite, clock drift, and delays in the signal caused |
| satellites work together to create plots on maps | | | | by the ionosphere and atmosphere of the Earth. |
| so GPS systems can easily make this information | | | | After the corrections are made, the master |
| available to the consumers that use these | | | | station transmits this information to a |
| products. | | | | geostationary satellite (one of two), which are |
| WAAS is still being developed through the joint | | | | located in a stationary position over the equator. |
| efforts of the FAA (Federal Aviation | | | | Since the information is GPS compatible (the signal |
| Administration) and the DOT (Department of | | | | structure is the same) a GPS receiver with |
| Transportation). The reason the DOT and the | | | | WAAS is able to read the signal from the satellite. |
| FAA are developing WAAS is actually to make | | | | At the present time, only people in North America |
| flight locations more accurate. WAAS works | | | | can use WAAS technology. GPS can be used in |
| together with GPS because GPS does not | | | | South America. However, WAAS will not work to |
| currently meet navigational requirements of the | | | | correct accuracy errors. This is because WAAS |
| FAA on its own. | | | | enabled GPS receivers cannot receive signals due |
| At this time, WAAS is five times more accurate | | | | to the fact that South America has no ground |
| than the average GPS system technology. In | | | | stations. WAAS technology is constantly being |
| fact, a GPS receiver with WAAS capabilities can | | | | tweaked and improved though, so in time it could |
| maintain an accuracy of three meters or less | | | | become available across the world. |
| over 90% of the time. Of course, the best | | | | For now, it is best to use WAAS enabled GPS |
| feature of WAAS is that it is built in to certain | | | | systems in open land or at sea. Since the |
| GPS systems. This means there are no additional | | | | stationary satellites are at the equator, it can be |
| fees and you do not have to order any additional | | | | hard to receive the transmission if you are not |
| receivers or other equipment for WAAS to work | | | | close to the equator or if the signal is being |
| correctly. Additionally, depending on the type of | | | | blocked by mountains, trees, or other natural and |
| GPS device you own, you may be able to | | | | man made objects that get in the way. |
| upgrade your GPS system to start using WAAS | | | | While WAAS technology is not perfect, it is much |
| capabilities if it does not do so already. | | | | better than what is currently available. As the |
| GPS alone faces problems such as ionospheric | | | | system improves, the accuracy will improve, |
| disturbances, precision timing, and orbit errors for | | | | making WAAS one of the leading technology |
| the satellites used. However, when used together | | | | systems for GPS receivers. You can find out if a |
| with WAAS, these three main problems, as well | | | | GPS system is WAAS compatible by looking on |
| as smaller errors in the GPS system are | | | | its package or searching online. |
| corrected. WAAS is also capable of providing | | | | |