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Spectrum Policy Implications of Growing Consumer Interest in Jamming

Below is your blogger’s regular column in IEEE Wireless Communications Magazine and appears in the March 2014 issue. We welcome alternative viewpoints and promise to print all received that are appropriate for a workplace blog. Send inputs here.

This is a magazine dedicated to communications, not electronic warfare. However, the issue of jamming is unfortunately intruding on civil communications on a growing basis. It does not take much use of your favorite search engine to discover the Internet marketing of jammers for cellular communications as well as GPS. There are even WiFi jammers and jammers for an anti-car theft system used in 37 countries called LoJack. These products need not meet any out-of-band emission limits (because they are being sold illegally anyway) and thus may well radiate in bands other than their intended targets. Thus, these commercially available jammers pose a real threat to many types of legitimate spectrum users.

The illegal nature of these systems leads to the policy option of controlling their use through marketing regulation. Most, but not all, countries allow their national spectrum regulators to prescribe standards for radio transmitters and forbid the marketing of noncompliant equipment through civil and criminal penalties. Unfortunately, the worldwide market for illicit drugs shows that this supply side regulation is not going to be completely effective. Indeed, the anti-drug marketing efforts in all countries are likely to be better funded than any practical anti-jammer marketing efforts. Furthermore, the rise of Internet-based marketing with offshore production and express shipping to the consumer further complicates supply suppression unless the production countries fully cooperate.

The spectrum community can learn from past efforts in illicit drug suppression that focusing on supply side suppression is unlikely to be successful without some attention to demand side suppression. Suppressing supply for an illicit product will only drive up its price if there is an actual demand for the product and the increased price is likely to attract more suppliers absent draconian penalties.

Perhaps the spectrum user community should be asking why is there a consumer demand for jammers today? It is hard to answer this comprehensively, but here are some thoughts. Cell phone jamming is rarely motivated by direct financial incentive. Hotels may have a financial incentive to jam guests’ cell phone to divert calls to high priced phones in hotel rooms — but this type of jamming is virtually unheard of. More common is jamming in restaurants, theaters, work places, and schools*. Such jamming appears to be more motivated by annoyance issues than direct financial return. In 2005, Motorola, a major producer of cellular equipment at the time, commissioned
a study on the annoyance issue from Donald A. Norman of the Nielsen Norman group, an engineering design consultant. Dr. Norman wrote,

We are in real danger of a consumer backlash against annoying technologies. We already have seen the growth of mobile-phone free zones, of prohibition against phone use, camera use, camera phones, in all sort of public and private places. The mobile phone has been shown to be a dangerous distraction to the driver of an automobile, whether hands-free or not. If we do nothing to overcome these problems, then the benefits these technologies bring may very well be denied us because the social costs are simply too great.

Annoyance with others comes from many sources. Some might consider this a social issue, but there might very well be technological solutions. After all, it is the technology that has provided the affordance — the technical terms that describes the ability to do some action — that is so annoying. Perhaps we could refine the technology so that it better affords politeness to others. (emphasis added)

Dr. Norman also discusses the issue of loud speech by cell phone users that he attributes to lack of sidetone in many cell phones and views as an issue that could be addressed in engineering design. The point here is that interpersonal friction resulting from cell phone use may be a key factor in the demand for cell phone jammers.

In Japan the cell phone industry is more attentive to interpersonal friction problems from cell phone use than in many other countries. Part of the instruction manual from a cell phone marketed in Japan has a section on “Mobile Manners” that recommends:

“Use your handset responsibly. Inappropriate handset use can be both dangerous and bothersome. Take care not to disturb others when using your handset. Adjust handset use according to your surroundings. • Turn off handset power in theaters, museums and other places where silence is the norm.
• Refrain from use in restaurants, lobbies, elevators, etc.
• Observe signs and instructions regarding handset use on trains, etc.
• Refrain from use that interrupts the flow of pedestrian of vehicletraffic.”

Telstra, an Australian carrier, has similar information for its consumers on its
website, but generally cellular carriers do not give guidance to their users on avoiding interpersonal conflict through cell phone use. It is likely that interpersonal friction is a major issue in stimulating the demand for jamming devices and reducing it through technical changes, such as changing technology to reduce user voice volume during calls, or consumer education will reduce consumer demand for jammers. Such demand reduction would then complement supply reduction through better enforcement by national spectrum regulators and is more likely to impact the use of consumer jammers than addressing either supply or demand independently.

If we cannot reduce the use of unauthorized consumer jammers through actions such as those discussed above, their use will seriously impact the telecommunications systems that readers have worked assiduously to develop, distribute, and operate for the benefit of our societies and economies.


*In France jamming of cellphones in prisons, theaters and concert halls is actually explicitly allowed under national law, France, Article L33-3, Code des postes et des communications électroniques, as amended by Loi n°2002- 1138 du 9 septembre 2002 — art. 47 JORF (Sept. 10, 2002)


CEPT/ECC Recommendation 04(01), updated February 2013, says “these discussions have made it clear that there is no legal basis to allow that communications be disrupted by jamming devices operated by the public”. However it goes on to say “CEPT administrations should not allow the placing on the market nor the use of jammers except in the very limited context of authorised use which may be permitted by a national legislation”.

Thus while the above cited French law permits jamming in prisons, theaters and concert halls, this CEPT recommendation is contradictory about permitting jamming by any member of the public in the specific case where it is authorized by national law. It is clear that at present FCC regulations do not permit any jamming by the public or state or local governments. Whether this is a necessary interpretation of 47 USC 333 is an issue FCC has yet to rule on.

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