A-GPS Update

Assisted GPS (A-GPS) improves location determination by obtaining “assistance” data from a network over the wireless communication channel. The result? Higher position accuracy, quicker location fixes, and improved coverage of service in difficult locations, such as urban and in-building environments. Also, in some cases, position calculations may be offloaded to a remote server, freeing the device’s processor to service more critical functions.

Until recently, all industry-defined GPS test methodologies focused on testing the performance of a device over a cabled RF connection, bypassing the GPS antenna and associated circuitry. Consequently, devices that pass all tests in the existing conformance standards may perform poorly in the real world. To determine real world performance of mobile devices with A-GPS, testing needs to include all relevant components.

CTIA – The Wireless Association® recently released Version 3.0 of its Test Plan for Mobile Station Over the Air (OTA) Performance. OTA testing is performed in a controlled radiated environment, called an anechoic chamber, using specialized equipment to provide a known signal to the device under test. A key aspect of this testing is that all signals are transmitted and received wirelessly, as they are in the real world. The arrival of A-GPS OTA testing is a very significant event for the cellular industry and users of mobile devices and will, ultimately, ensure the consumer of a superior end-user experience when using location tracking technology.

To learn more about A-GPS and the wireless OTA test solutions offered by ETS-Lindgren and Spirent Communications, read the white paper available at www.ets-lindgren.com/resources titled “A-GPS Over-The-Air Test Method: Business and Technology Implications” by Michael D. Foegelle of ETS-Lindgren and Ron Borsato of Spirent Communications. For more: www.mwjournal.com/testbench_12010.