Electronic Espionage Detection and Prevention
|
Electronic Espionage Detection and Prevention |
|
Partner with TSCM Technical Services-- Special information for Security and Investigative Firms How do I get a price quotation for your services? Contact TSCM Technical Services Hints, Suggestions, and Interesting
historical info
|
Radio Frequency Detection Equipment Transmitter detection is a tricky process. The bad guy has the entire radio frequency spectrum to choose from. And has a whole host of different modulation techniques to use. Modulation techniques control how the sound is transmitted. Common ones include those you use every day: Amplitude Modulation (AM), Frequency Modulation (FM), Narrow Band FM, and others. More exotic modulation types include single side band, subcarrier, spread spectrum, frequency hopping and various other digital types where the analog audio is converted into data. Transmitters can operate on frequencies as low as 20 kHz, using the AC power lines or telephone lines to carry the signal. Transmitters can operate up into the microwave frequencies, too. The TSCM technician does not know what background, ability and equipment the bad guy has access to, so the entire spectrum and all of the different modulation techniques have to be considered and examined. Plus, there really is no way to tell how much power the eavesdropping transmitter has. It might be an 80 milliwatt transmitter that will go several hundred yards or a much weaker transmitter than only has to transmit a few dozen feet to a hidden receiver. This makes the RF sweep a detailed and time consuming task. Quick and easy is not a concept that good RF TSCM technicians are familiar with. Frequency Coverage Traditionally, the frequency ranges covered during a TSCM sweep start just above sound and end in the microwave ranges. Our equipment can detect transmissions as low as 20 kHz. Transmitters using frequencies this low generally do not use radiating antennas as do higher frequency transmitters. These low frequency threats require very long antennas (maybe as long as several hundred yards) if they are to radiate or transmit a signal for any sort of distance. Instead of radiating through the air, low frequency eqavesdropping transmitters make use of existing building wiring: their signals are carried on the AC wiring or are coupled onto the telephone wiring. The signals from these sources only radiate a few inches from whatever wiring they use. Our RF detection equipment couples directly to building AC and telephone wiring so any signals carried by the wiring can be picked up right away as strong signals for quite some distance. These transmitters are called Carrier Current transmitters Most RF detection equipment tops out at 1000 Megahertz. And currently 98% of all eavesdropping transmitters will be found below this 1000 MHz threshold. In fact, 98% of all radio signals that the TSCM technician has to evaluate are below 1000 MHz. This means that at least 2% of the signals are going to be above the 1000 MHz threshold. In fact, there are products that can be used for eavesdropping operating at 2400-2600 MHz that can be bought for under $250 at consumer electronics stores. We recognize this escalation of frequency range as a serious problem. Our equipment will detect transmitters operating at 7 times higher than the traditional range. We continually ask the question "how high is high enough?" Currently, we put the ceiling at 7,000 MHz. When we recognize a realistic threat higher than 7 GHz, we will extend the range of our sweeps to cover. Area of Coverage We use a laboratory standard spectrum analyzer, ISA's ECR-2. Spectrum analyzers are the tool of choice for all major TSCM providers. This analyzer can cover a large area --up to 32,000 square feet in one sweep. The reason we can sweep such a large area is that the ECR-2 has remarkable sensitivity. High sensitivity is the ability to detect weak signals from a distance. To be certain of detecting even low powered transmitters, we calibrate the area prior to the sweep using low power RF sources to make sure that even the lowest power signal will be detected. Other popular "all in one" correlating transmitter detection products claim to have high sensitivity, but field tests by our staff prove that the real detection range for low power transmitters and microwave transmitters is typically no more than 40 feet. Our spectrum analyzer will cover an area roughly 5 times that size, making a sweep more cost effective and much more accurate. All equipment selected for use by TSCM Technical Services is carefully evaluated to make sure the sweep is as accurate and efficient as current technology allows. Computer Control We control the analyzer with a computer running ISA's SmartScan software. SmartScan automates the RF sweep and makes it much more accurate. It also frees up a technician for other activities and tasks. Manual RF sweeps take upwards of 1 to 2 hours. Using SmartScan, a sweep usually takes less than twenty minutes of actual operator time. It also lets us compare signals outside a facility to signals inside to detect transmitters more efficiently. All RF sweeps are archived in the computer for reporting capability and for comparison against previous sweeps at a facility speeding up the survey. SmartScan offers two types of reports of the results of the RF sweep: The first shows a list of all of the signals detected form the first to the last or from the strongest to the weakest. The second type of report is a graphic display of the spectrum in frequency spans from 2 MHz in width to 7 GHz in 1 GHz wide steps. Any signal can be highlighted and printed in detail. SmartScan also contains a sophisticated analysis algorithm for identification of spread spectrum transmitters that are very difficult to detect and locate using manual methods. Click here to see a sample of the SmartScan display.
All digital telephones are tested for RF emanations. Telephone lines for distances around the site of the survey are examined with the RF spectrum analyzer to detect transmitters located at remote from the site. AC power lines are tested for RF transmissions. CATV cabling is tested, also. Special Event Services We monitor the RF spectrum in real-time during sensitive meetings when required. This technique will detect the activation of a cellphone or other transmitter in the area during the meeting. Although we can assure you that the area is clean when the sweep is completed, we can not prevent a device from being carried into the area after we have completed the survey. Devices could be carried in by service personnel or could consist of a cell phone configured for auto-answer brought into the meeting by an unfriendly participant.
|
Send mail to info@tscmtech.com with questions or comments about this web site.
|
