A metrology geek will go to extreme lengths to ensure that their measurements are the best, their instruments the most accurate, and their calibration spot-on. There was a time when for ...

The National Academies of Sciences, Engineering, and Medicine are private, nonprofit institutions that provide expert advice on some of the most pressing challenges facing the nation and world. Our ...

The global positioning system (GPS) constellation comprises 24 or more satellites in six orbital planes at an altitude of approximately 12,550 miles. Synchronized with on-board atomic clocks, the ...

One of the more interesting facets of GPS is that, at least from the receiver’s point-of-view, it’s a fairly passive system. All of the information beamed down from the satellites is out in the ether, ...

XLi SAASM, combining high performance and extensive functionality, also granted approval by GPS Joint Program Office (JPO) for meeting latest security requirements San Jose, Calif.—Symmetricom, a ...

The problem is that a cell base station would be many orders of magnitude more powerful to a terrestrial observer than a GPS signal. It doesn't take much to raise the noise floor too high to pull in a ...