Blog Editor’s Note:

Why do we keep posting these things? Doesn’t everyone know that there are tens, if not hundreds, of thousands of GPS signal jammers out there being used by everyone from delivery drivers to Mafia bosses?  So what? No one has died!  Nothing really bad has happened!

Not so. We do this because:

  • Only a few people among the population as a whole know about the problem. And, of the ones who do know, many would like to think it is not as widespread as it really is. There’s no organized monitoring in the US, so it is only through anecdotal reports like the one below that we can even glimpse the scope of the problem.  
  • People may well have died, and bad things may have happened. Drivers distracted by a malfunctioning navigation system. Cell phone calls to 911 that don’t go through the first time. First responder radio systems disrupted or slowed down. All of these could result in fatalities – but it would be almost impossible to trace the cause to a small, low powered jammer. 
  • If we pay attention we can see the future. Even if no one has died or nothing really bad has happened yet, we know it will. Combine the importance of GPS to critical systems and infrastructure with enough disruptions and the law of large numbers will take over. Eventually something really bad will happen. Out of every 100,000 drivers, 23 will die every year on the road. It only took about 120 airliner hijackings before we had 9/11. How many jammers on the road will it take before there is a multi-fatality pile up, a network unravels, or airplane misses a landing?

So we will keep posting reports like this until everyone understands that this is a problem and something has been done to fix it.

Qulsar Uses Chronos Equipment to Detect 1,894 Jamming Events in 20 Months

During a tutorial at the recent Workshop on Synchronization and Timing Systems in San Jose, CA, Dr. Marc Weiss discussed the prevalence of GPS disruptions and cited the experience of Qulsar, Inc. whose offices were adjacent to the workshop venue.

Qulsar has had a Chronos Technology device in their lab to monitor for transmissions in the GPS frequency for several years. The antenna is on the roof of their two story office building. San Jose International Airport, and three busy freeways, the 101, 87, and 880, are nearby.

The Chronos monitoring device detected 1,894 signals in the GPS band strong enough to interfere with GPS receivers between October of 2016 and May 2018.

Though the average was about three events per day, there was significant variation in the number of events by time of day (activity peaked around noon) and day of the week (much less activity on weekends).





Blog Editor’s Note: As would be expected in any high traffic area such as this, there have been a number of fatal and serious injury traffic accidents over the last several years. It is impossible to know if GPS disruption contributed to any.