In conjunction with path studies and/or frequency coordination, Global Positioning System (GPS) receivers are available for rental to determine latitude and longitude.
A brief word about GPS receiver accuracy and FCC licensing. The FCC requires latitude and longitude to be within plus and minus 50 Feet, North American Datum 83. Reference FCC Rule Part 101.103
The GPS receivers as used by aviators and mariners are are only accurate to within three hundred (300) feet, with government spoofing known as selective availability turned off. This is due to the following errors:
Satellite clock error 10-30 Feet
Ephemeris error 10-30 Feet
Receiver error 15-40 Feet
Atmospheric & ionspheric errors 100-200 Feet
Thus we see the error in the average GPS receiver to be, 135 to 300 Feet.
GPS receivers do not yield accurate vertical ground elevation readings. The vertical error is typically twice the latitude and longitude error. If renting from us, we maintain a database that uses an approved FCC averaging system to determine the ground elevation.
The GPS receivers provided by us, are high quality units that provide a solution to within an accuracy of thirty (30) feet. This accuracy is obtained by averaging multiple positions. These receivers are ideal for field use, in that they are light weight, accurate and simple to use. They provide an optimum solution for FCC licensing and path studies.
Our GPS units are also useful for a number of other applications when used in conjunction with a computer and optional software. For example they can transmit Society of Motion Picture Television Engineers (SMPTE) and European Broadcast Union (EBU) time code signals for both film and video production. Other applications include an output compatible with popular spreadsheets and in creating scale overlays for any topographical map.
All units are shipped by Federal Express and must be returned in the same manner.
Latitude and Longitude are defined by various datums or geographic ellipsoids. The FCC & FAA both use North American Datum (NAD) 83. Another Datum commonly used by surveyors is NAD 27. Different datums result in different answers in latitude and longitude at a specific point. Municipal maps, road surveys etc.in "state planar coordinates", are sometimes available with great accuracy in small to large urban areas. We support translation services for over six hundred (600) coordinate systems.