Beating Remote Control Signal Jamming

There has been tons of hype associated with so-called remote "signal jamming" within the news lately. Signal jamming refers to the shady and highly illegal practice of employing a remote device - like those wont to open garage doors or entrance gates - to "jam" the signal transmitted by the remote that you simply use to lock your car, arm its alarm, etc.

The problem

Let's first take a glance at the technology behind it all. The hand transmitter - or remote, because it is more commonly known - transmits an RF signal that's picked up by a receiver. The receiver, which is essentially a tuned circuit, successively converts this signal to an output that can then be wont to operate a gate motor, activate a car's central locking, or regardless of the case could also be. In South Africa, the waveband on which all remote devices operate is 433MHz, as decided by the regulator for the South African communications sector, ICASA. This band is shared by all RF devices.

As illustrated during a recent newscast segment, criminals abuse this novel technology by pressing and holding their remotes at precisely the same time as an unsuspecting vehicle owner is endeavoring to remotely lock his or her car, or to arm the vehicle's alarm, and in so doing leaving the car susceptible to intrusion. It must be remembered that the signal sent out by these transmitters is relatively small, and may thus be swamped by interfering signals.

Naturally, the reason of remote controls is to supply the user with convenience and peace of mind, and each possible precaution has been taken to make sure that remote controls are as secure as possible, with certain gate motor manufacturers even implementing revolutionary rolling-code technology to stop "code-grabbing", another dastardly practice favored by modern criminals. Remote controls using rolling code technology never transmit an equivalent signal twice, dramatically increasing the safety of RF communication and rendering code-scanning devices completely useless.

However, as discussed earlier, even these highly secure remotes are required to work at a frequency of 433MHz, and intrinsically criminals are known to use them for signal-jamming.

The Solution

Most vehicle manufacturers equip their cars with some kind of confirmation signal, be it a beep, double beep or flashing of the headlights, to point that the vehicle in question has been securely locked or the alarm has been armed, etc. All vehicle owners are therefore advised to concentrate carefully for these confirmation signals before leaving their vehicles unattended. it's better to adopt a pro-active approach when handling this new breed of tech-savvy criminal.