The Truth about Cell Jammers

Posted by , , at 7:00 am

A few weeks ago, a customer on Facebook presented us with this question:

“My area has had several burglaries, and police report the thieves are using GSM/Cellular Jammers to prevent alarm systems from accessing a cellular signal while they burglarize the houses. Is my FrontPoint system susceptible to this type of device?”

Questions about cellular monitoring and its reliability in the presence of a cell jammer have popped up more often in recent years, as the home alarm industry continues to shift towards cellular monitoring. We’ve talked about cell jammers before, but this customer’s concern presented the perfect opportunity to provide further clarity.

A Cell Jammer’s Use

Cell jammers are devices used to prevent and block cellular signals, primarily in mobile phones. They’re often used to disrupt signals in locations where silence is expected or where using a phone would be impolite or rude.

Commercial use of cell jammers is illegal in the U.S., but this has not stopped people from using them; a quick Google search will unveil many sites selling the device.

The Effect on Cellular Alarm Systems

We know cell jammers can work on mobile phones, but can they also block the signal in your home security system with cellular monitoring?

The answer is yes, cell jammers can disrupt the signals of cellular radios because they use the same frequencies as mobile devices. Sensors will not be affected, as they operate on a separate military-grade frequency, but are limited in range.

This probably is not the answer you wanted to hear, but be reassured, you can still trust your cellular alarm system.

There’s a reason both new and old home alarm companies are choosing cellular technology: cellular monitoring is still the safest – and most reliable – form of monitoring available. And here’s why.

Real Burglaries v. Hollywood

It comes down to the true nature of burglaries. They’re often portrayed in movies and television as pre-determined, meticulously planned and skillfully executed events. This is very inaccurate.

Burglaries are rarely pre-determined or carefully orchestrated. Instead, they’re random and opportunistic acts.

Wire Cutters are the Tool of Choice

Burglars are much more likely to be carrying wire cutters than a cell jammer.

This is because wired security systems make up the majority of the home alarm market, and they’re still being sold by the majority of alarm companies – despite their obvious flaws. As a burglar, the likelihood of running into a wired system is much greater than a cellular system.

There’s also the issue of obtaining a cell jammer. As we mentioned, cell jammers are illegal for commercial use in the U.S.

Although burglars have a disregard for the law, taking a step further by obtaining a cell jammer is likely not worth the risk. Whereas, wire cutters are legal and easy to purchase.

The Burglar Mindset

A burglar’s motives is another reason why a cell jammer is not a realistic option.

As we mentioned, burglaries are often random, opportunistic acts. Burglars are not George Clooney or the rest of the Ocean’s Eleven looking to pull off an elaborate heist.

Burglars are looking for low-effort, low-risk opportunities. And since most homes equipped with a security system are wired, cell jammers are not worth it for burglars. They’ll be carrying wire cutters instead.

Another factor to consider is the cost: wire cutters are extremely cheap and cell jammers are much more expensive. Since there’s no guarantee that a home will be protected by a cellular security system, why would a burglar opt for a more expensive tool that may be unnecessary?

Cell Jammers are Not Effective

Worst case scenario, a burglar chooses to use a cell jammer instead of wire cutters. There is no guarantee it will work.

The cellular radios found in alarm systems vary from system to system. Some belong to different carriers, while others feature newer technology. And technology is constantly changing.

The mobile industry is in the forefront of innovation, and security companies are quick to adopt technologies that are introduced.

The most affordable cell jammers have a limited range. If a customer places their panel in a recommended location, away from doors and windows, a burglar will have a hard time knowing if they’re in range.

Cellular Home Security is Safe

As you can see, there are a lot of reasons why a burglar simply wouldn’t put forth the effort to lug a cell jammer around the neighborhood. The combination of unreliability, high price and high risk make it extremely difficult to justify, especially when wire cutters are (unfortunately) a proven tool.

We understand that our customers, and discerning home security shoppers, are concerned with cell jammers. And we hear you! We do everything we can to give you with peace of mind, not only by providing the best and safest home security, but also by providing you information and knowledge you need. Please tell us, what other questions do you have about home security?

Comments (16)

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  1. Jane Ruddick

    I live in Costa Rica in the mountains..My one and only neighbor has sued me, case was dismissed..Now, as a pay back his alarm has been going off at night only for going on two weeks…We have called police, our attorney, etc…NOTHING..
    How can we block the signal to shut off? We cannot cut any wires or go in there and take the speaker off, we would be the first they would suspect..It is his party house, he is Costa Rican, lives in another town. He is a real slime bag..Get so drunk, shoots guns into the air, music like at stadium level…HELP

  2. Theresa mcdermott

    Can neighbor use jamming device to cause my swann surveillance camera to blurr for the amount of time to do vandalism

  3. Ana hall

    Our house was recently burglarized, the burglar was warned ( by cell phone) that we had pulled not the street making the getaway easy. I was thinking perhaps a cell phone scrambler would be my answer but now I’m worried my alarm will be affected. Thoughts?

    • Katie Rynex

      Ana, if you were to use a cellphone scrambler this would effect your panels communication to the monitoring station. We hope that this answers your question and ask that you please let us know if you have any other questions!

  4. George Clooney

    Seems to me that doing all types of fancy configurations or algarythyms would not make a bit of difference. If someone is jamming the wifi signal in the building, all wifi is blocked including the signal coming from the cable/wifi company. Thus it does not matter if the alarm is smarter as if the cable box is not smarter, game over.

  5. Jim

    I have been pre wiring homes, installing and programming systems from DSC, inter logic, and Honeywell for about 5 years and have worked on both commercial and residential panels. Individual wireless transmitters and receivers are supervised and enrolled with the panel by serial number. That means that they send a signal to the panel on a set interval. If the panel does not see a signal from that specific serialized transmitter it will trip the alarm. It would take fairly sophisticated frequency sweeping to detect a specific frequency to mess with then also send that signal at predetermined intervals. A simple “jam” would be detected almost immediately. They could however jam you cell signal slightly more easily, however the customer would then be getting phone calls from there monitoring company and an eventual police dispatch. I don’t know a lot about front point specifically but the word “jam” is being used fairly loosely here. Hope this helps someone. This started as a Google search of ways I could improve on my own installations while I’m sitting in a hospital waiting room at 1:00 AM.

  6. kathleen

    My system was jammed Repeatedly. Burglars are sophisticated. That is utter nonsense that they don’t use jammers I BET 90 percent of them do. Security companies have to catch up. My life was ruined over this major home invasion and theft.

    • Aaron

      More details about this event would be appreciated. Sorry you had to deal with this horrible experience.

  7. Anonymous Coward

    “Sensors will not be affected, as they operate on a separate military-grade frequency, but are limited in range.”

    There is no such thing as a “military grade frequency”. Due to the low power output of the sensors they can be jammed very easily (easier than the cellular radio). In fact using language like that could even be considered false advertising. I would be TOTALLY shocked if the sensors are not in the ISM band.

    Radio technology is moving faster than companies like this can move. Software defined radios are all the rage currently and could EASILY be used as a jamming device. Even worse is this technology could potentially allow thieves to know when people are home by monitoring the signals coming from the sensors.

  8. Dennis

    With all the technology floating around there must be a way for the Frontpoint system to be designed to send a unit specific pulse of some kind to the monitoring outfit every 15 sec or so. The receiver would expect a pulse from the unit on that interval; not receiving it would indicate a communication problem, perhaps a jammer. A lost communication alert could be initiated to a monitoring person, who would call the appropriate folks. We have two numbers for them to call, that are not normally at the same location. So some contact could be made. If the incidence of jammer use is as low as you say, and the pulsing electronics is automatic, the added cost should be reasonable for those who feel they want it. Just a concept – the devil is always in the details, but I expect it could be figured out how to do it.

  9. J Cohn

    I should think that a partial Faraday cage that blocks all but line of sight to the nearest cell towars would help. They’d have to know where the cell towers were in relation to the location so they could stand in line with the communications.

    Put the antenna in the ceiling or on the second floor and the first floor can be blocked from the cellular jammer.

    • aetheriadraconis

      Yes, “keep alive” ping every N seconds is the only way to protect against jammers, but I don’t think it’s feasible using modern GSM/4G networks, because it will require uninterrupted connection.

      Another real problem is jamming of the wireless sensors themselves and these jammers are available, despite what article says. The only real guard here would be installation of wired sensors/cameras, which is, of course, much more expensive.

  10. KB

    I have to agree with Chris, the arguments for the safety of your systems is pretty weak, basically siting the laziness of burglars which could be a baseless assumption, what are the stats? How many burglaries have been executed using this technology and where? How many of your systems have been hacked? What steps is Fronitpoint taking as a precaution or are you just hoping that all burglars, rapists and murderers are cheap, lazy and low-tech?

  11. chris

    The arguments used to minimize the jammers’ effectiveness are extremely weak… and please, stating that security companies are quick to pick up new technology is a complete nonsense. You are still using wireless technology of the 90’s… probably unencrypted etc?

  12. Tom

    Can we back up the cellular system with an analog line and have both?

    • Jamie Botzer

      Hi Tom, that’s a great question. We want our customers to have the safest product on the market, and that is a cellular system. We understand why you might want some sort of backup and we do offer other solutions for those customers who live in an area that does not have any cellular reception. These instances are handled on a case-by-case basis. Of course, we want you to feel good about your home security. If you give us a call, one of Support Specialists can get a better understanding of your home security needs and provide recommendations.