In response to recently released test results and ensuing discussion over the proposed LightSquared broadband network, JAVAD GNSS Inc. has released a white paper titled, “The Real Interference Issue: Political Noise.”
In response to recently released test results and ensuing discussion over the proposed LightSquared broadband network, JAVAD GNSS Inc. has released a white paper titled, “ The Real Interference Issue: Political Noise.” Written by Javad Ashjaee, the company’s president and CEO, the paper says the interference problems documented through test results are “entirely caused by poor design of GPS receivers.”
“The GPS interference issue is a perfect example of how Washington is allowing politics to influence a technical debate,” the paper states. “Opponents of LightSquared are trying to deal with the GPS interference issue by employing armies of lawyers and lobbyists who either don’t understand the scientific facts or are lying about them. Instead, it would be much better for those who are making much of the noise about LightSquared, to spend money on research and development to help solve the problem.”
In response to the reports that 75 percent of low-precision receivers failed in recent testing, the paper says the 1-dB loss in signal-to-noise ratio failure threshold is important to note for two reasons. “First, most receivers have up to 20-dB of margin on signal-to-noise and users most likely will not even notice a 1-dB loss. Second, if you take any one of the so called “failed” receivers near many existing transmitting systems (like AM and FM radio and TV towers) you will see that they will lose some dB’s of signal-to-noise or they may completely stop functioning. Should we force all such transmitters off the air? Or better yet, should we demand that GPS receivers that are being used in critical applications have protection against existing systems?”
The paper ends with a challenge to engineers who are interested in examining the issue in more detail.
