Plan To Jam Mobile Phones In Schools Is Madness

Mobile phones in schools. If you’re a teacher, school staffer, or a parent, you’ve likely got six hundred opinions about this very topic, and you will have had six hundred arguments about it this week. In Australia, push has come to shove, and several states have banned the use of mobile phones during school hours entirely. Others are contemplating doing the same.

In the state of New South Wales, the current opposition party has made it clear it will implement a ban if elected. Wildly, the party wants to use mobile phone jamming technology to enforce this ban whether students intend to comply or not. Let’s take a look at how jammers work in theory, and explore why using them in schools would be madness in practice.

Cellular Jamming 101

In general, mobile phone jammers work in a relatively simple fashion. They simply random noise broadcast radio frequency signals on the same frequencies used by cellular networks. If the signal from the jammer is powerful enough, it will drown out the signals from cellular base stations, and stop phones from making contact with the network.  Typically, broadcasting noise at high power across cell phone channels is all that’s required to successfully jam all communication.

You could make a cell phone jammer yourself, but you really shouldn’t.

Depending on the amount of power you put out, and the antennas you use, you can vary the area affected by your jammer. Of course, measuring this area is an inexact science. In much the same way you can’t stop your home WiFi network from reaching outside the front gate, you can’t readily limit a cell phone jammer’s output to, say, the boundary of a schoolyard.

And therein lies the problem with using cellphone jammers in schools. Given that most schools are in built-up areas, Lorain High School hallwaythere is a high likelihood of jammers spilling over to mobile phone users in surrounding homes and businesses. The outcomes would be profoundly negative in all cases. At best, residents and workers would be deprived of access to connectivity they need to do their jobs and pursue their very lives. At worst, emergency calls could fail to connect, and lives could be put on the line.

It’s for this reason that cellphone jamming is very much illegal in Australia, and most everywhere else for that matter. It doesn’t matter whether you want to jam signals in your own home or business, or just have a jammer in your pocket to keep your devices in the dark on the go. Owning, using, or supplying a jammer is illegal in Australia. It’s thanks to a permanent ban put in place by the Australian Communications and Media Authority.

Interestingly, though, there is a limited exception to the permanent ban, and there has already been a live trial jamming technology within the state of NSW. Via a special exception granted by the ACMA, the government has implemented mobile phone jammers in the Lithgow and Goulburn Correctional Centers. Since mobile phones may enter a prison as contraband, the jammers act as an extra measure to help prevent their use. The jammers were first trialled in Lithgow beginning in 2013. The trial aimed to determine whether the jammers would unduly interfere with regular mobile phone users outside the jail. After the trial proved successful, an ongoing authorization was granted in 2018. A trial at Goulburn Correctional Center is ongoing. In this case, the Goulburn facility exists in a more populated area, and thus there is a greater risk of the jammers causing problems for surrounding residents. As per requirements of the ACMA, the devices used in Goulburn may not cause radio emissions above -128.5 dBm/kHz outside the prison facility. The intention of this measure is to make sure legitimate phone users outside the prison are not affected by the jammer.

It’s Problems All The Way Down

While the authorities have largely supported the use of jammers in prisons, schools are another thing entirely. Jammers would affect students, teachers, and staff alike. They would also affect parents at school drop off, and any contractors working in or delivering to the school. Few of these people would expect to be cut off from their phone service, but jammers don’t discriminate.

Lorain High School hallway” by Matt Dempsey

The blanket use of jammers in schools would thus present concerning safety issues. Any emergency calls would have to be made via landline. This could introduce great delays if somebody is injured out on a playground, on the outskirts of the school, or in a building without a phone line. Indeed, schools these days have far fewer landline phones due to the rise of the mobile phone. Plus, these are not accessible to students or visitors, either. It would be a tragedy for a student to suffer a medical emergency and not have help arrive in time because a jammer was blocking calls.

There are issues with the realities of jamming capability, too. Strong jamming will leak beyond school grounds and cause condemnation from surrounding residents. Meanwhile, if jamming is done conservatively, the jammers may not be effective at their job. Industrious teens with smartphones would readily find any jamming blackspots within days. In fact, you could likely map areas where jamming had failed by taking a drone up and plotting out clusters of disaffected teenagers.

Wait, What?

Curiously, there has been little talk of the specifics of the policy. However, one thing stands out: there has been talk of a proposal by a company referred to as “Educell” which has no visible online presence we could find. Speaking to media, NSW Labor Party leader Chris Minns also hinted that emerging technology could block students from making calls, texting, and using the internet, while allowing emergency access to those with medical conditions. If that is the case, that would require some kind of advanced cellular device within the school itself. It would have to force student phones across all networks to connect to it in place of existing conventional cell sites. Only then could it allow emergency calls while blocking other uses.

It seems unlikely such a device could fit within any school budget, nor gain the approval of network carriers to effectively pull a man-in-the-middle attack on their subscribers. It would also require a continually-updated white list to allow staff to use their devices while blocking those of students. Any visitors to the school would also be subject to blocking unless they had their number whitelisted as well. Alternatively, such a system could operate on a blacklist method, but then students could simply buy a new SIM card or provide the school with a fake number to avoid being subject to the restrictions.

Neither Hackaday nor the ACMA has seen detailed technical specifications on Educell’s tools. One suspects such flexible phone banning tools are more of a nice-to-have idea, rather than something that is readily practical with solutions available on the market.

Reality Check

In reality, the schools of NSW could instead follow the example of those in other states. Teachers have simply used their disciplinary authority to punish students for using their phones in class. Other schools have mandated that they remain in lockers during school hours, or in special Faraday cage-like pouches to ensure they’re non-operable. All these measures are far cheaper and simpler than implementing jammers. They also have zero effect on the surrounding community. Plus, they don’t stop staff, parents, and visitors from using their own phones for work purposes or in an emergency situation.

The proposal has quickly led to wild headlines comparing the treatment of students to prisoners. That, combined with the technical infeasibility of the proposal, may lead to this jammer policy getting quietly dropped for a more conventional ban on phones in schools. If not, though, expect the road towards school-based cell jamming to be a bumpy and uncomfortable one for everybody involved.

331 thoughts on “Plan To Jam Mobile Phones In Schools Is Madness

  1. If keeping students off their phones seems to be a problem for which other solutions are lacking, signal jamming in a school can’t be taken off the table “just because” any more than it is for Goulburn. If jamming seems like it would cause problems, then these problems need to be quantified, and experiments run to see if they can be worked around.

  2. Stop making schools resemble prisons even more than they already do.

    Jamming will threaten safety of life in emergency situations.

    Treating children like prisoners is an equation for failure.

    Have fun ruining your country!

  3. @Cottrill:
    You sound like the fool, who after an accident refused to take a sobriety test. Flailing about and spewing b.s. About knowing your rights, the constitution, free county, …
    Everybody else just snickering while they haul you off.

    It’s OUR world, OUR school. Society dictates the rules.
    “…the parent ALLOWED them to 1. have a phone 2. Want a direct communication to said child and 3. Allowed it to go to school with them.”
    Re: 1. OK. 2. Must be without disruption 3. OK
    That fact that you WANT instant, direct communication with your child, might or might not be possible without a disruption and burden to others. WE (including you) will determine that. I want to know that my tax dollars are being used to educate, effectively and efficiently. If you think YOUR want exceeds other issues, keep your kid at home.

    My school has a phones in lockers policy. No problems with my two kids going thru. They could always reach us when necessary. If we needed to contact them immediately, we called the office, and they were instantly pulled out of class.

  4. “Teachers can just use their disciplinary powers…” Lol good one. That would require local administrators to not waffle every time a kid spurgs out and their parent goes full Karen over the subject. It would also require district administration to not be actively engaged in cooking the books on school discipline issues in order to obtain some moronic federal funding hurdle based on number of incidents. The stark reality is that most parents of the kids that have issues with phone usage aren’t raising their kids anyway, and actively support their child’s bad behavior.

    I don’t care about jamming the whole campus, I just want to bring the noise floor up in my classroom to the point that mobile data won’t work in a 5m radius. That’s achievable and the kids can still make Tik Toks in the hallways.

  5. Doing this would only promote decentralized+encrypted solutions like Briar, since that would be one of the only ways school gossip could circulate.
    I think that if the government wants to shoot itself in the foot and have another “firechat”-like incident, go ahead and jam the most tech-savvy segment of your own population.

  6. Many smartphones can operate just fine using a wifi connection to the internet. Jamming cellphone signals would not effect wifi. Jamming cellphone signals seems overkill since it would not be 100%effective and th set e are already non-jamming alternatives that would not effect teachers, staff; and the surrounding community.

  7. Jamming is bad even at low transmit powers. It will cause a lot of unintended interference let alone safety issues.

    Rather then jam install devices that detect and alert of a nearby active phone in the desks and identify the offender. Hopefully alerting it gets to the point positive peer pressure makes students embarrassed they triggered the alarm. Then have it amount to some type of infraction or absence. Too many infractions have real consequences like detention, summer school, suspension, or late graduation.

  8. Kids are at school to learn.
    They can’t learn if they are distracted, whether by the view out of the window, harassing the kid infront of them, or chatting to their mates. Playing with a mobile device is just another distraction and is subject to the whatever processes are available to the teacher.
    At our local schools the policy is for kids to put their mobile phone or similar into a box when they enter a classroom and collect it on the way out. Non-compliance is subject to the same disciplinary processes any other breach would invoke, from a gentle reminder.
    There’s no need to bleat about violation of human rights, or psychological damage. Just common sense. As the original poster made in their Reality Check paragraph.

  9. All the comments in favour of this, ahaha
    Phones in school are still good, get with the times. And seeing as this is America…what if there is an…incident? How are people meant to call for help? Just an absolutely inconsiderate, thoughtless, illogical idea.

    Speaking of thoughtless…why do I have to scroll all the way to the bottom to leave a comment on mobile? I mean it’s 2023 and we’re all technophiles out to solve problems.

  10. Dont be so vague!
    On 24 March, you say, effectively ” the current NSW opposition proposes jamming in schools”
    Very close to an election date which chaged the NSW goverment.
    So who were this “current NSW opposition”.
    Technologocal geniouses

Leave a Reply

Please be kind and respectful to help make the comments section excellent. (Comment Policy)

This site uses Akismet to reduce spam. Learn how your comment data is processed.