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Blog Editor’s Note: An interesting overview article that also includes some tech details and several case studies. We especially like case studies as they are a good way to make what “might happen” real. We note that folks who jam and spoof usually take pains to avoid detection. Thus, whenever these cases make it into the press we are seeing both the tip of the iceberg and a glimpse of more widespread current and future activity.
The article concludes with some information on how to make receivers more robust and resistant to jamming and spoofing. It’s actually a bit of an ad for one of our corporate members. they are a good company and we strongly agree these measures can be helpful and should be used where and whenever possible and affordable.
We also think that establishing a terrestrial wireless source of PNT that could be easily accessed would (1) deter a lot of jamming and spoofing as it would have less impact on serious PNT users, and (2) provide users an alternative to relying entirely on weak space-based signals that could be disrupted from any number of accidental, natural, or malicious sources. Some nations (e.g. China, Russia, South Korea, among others) have already done that. Most have announced the reason for doing so as avoiding space as a single point of failure.
In the U.S. there is a law that requires such a system. Unfortunately the last administration ignored it and the current one has yet to act.
We hope the current administration’s policy is not “Sit tight and assess.”
GNSS Jamming: An Omnipresent Threat
The deployment of jammers that are easily available on e-commerce websites, military conflicts, faulty wireless equipment, or poorly designed radio frequency transmitters can disrupt or jam GNSS/GPS signals. Whatever be the cause, the consequences of jammed GNSS signals can be far-reaching.
The use of Global Navigation Satellite Systems (GNSS) has become ubiquitous in our lives. Today, there is hardly any human or economic activity in which one of the satellite systems, such as, the GPS (USA), GLONASS (Russia), Galileo (Europe), and BeiDou (China) is not used. Besides, countries like India are also launching their own systems like the Indian Region Navigation Satellite System (NaVIC).
With ever-increasing reliance on GNSS in every walk of life for position, navigation, and timing (PNT), within the framework of location the need for bulletproofing these systems from intentional and unintentional disruptions (jamming and spoofing) is even greater than before. Of all the satellite navigation systems, GPS (Global Positioning System) is most widely used around the world.
Since GNSS signals travel a long way from geostationary satellite constellations, orbiting at approximately 22,000 miles (35,000 km) above the Earth’s equator, they become weak by the time they reach the earth stations/receivers and are susceptible to interference. Typically, GPS signals operate in three radio frequency (RF) bands: L1 (1575.42 MHz), L2 (1227.6 MHz), and L5 (1176.45 MHz). Due to the weak nature of the signals, any form of RF interference can cause severe disruptions to position, velocity, timing, and navigation, which are critical in virtually every industry and sector. Any disruption can lead to partial or full jamming of GNSS/GPS receivers and potentially cause serious harm and economic losses.
