Once again about cell phone blockers..
MAKSIMOV Andrey Mikhailovich
ONCE AGAIN ABOUT CELL PHONE BLOCKERS
The widespread use of mobile communications has also given rise to problems of protection against cellular telephony. The use of cellular telephones has long been prohibited in some government agencies and restricted areas, and in the offices of law enforcement agencies. They fight against handsets in prisons and camps, in educational institutions, especially during exam periods, in some hospitals (they affect the operation of pacemakers), and on board airliners (they affect navigation equipment). They insist on compulsory observance of silence in movie theaters and concert halls, in churches, museums, etc. It is becoming the norm to prohibit the use of cellular telephones during important business events — meetings, conferences, and negotiations, especially where confidential issues are discussed. This is due to the fact that any cellular handset is potentially a ready-made eavesdropping device, capable of secretly transmitting information via cellular communication channels from others. Special technical means operating in the GSM standard and using regular SIM cards have also become widespread.
It turned out to be impossible to solve the problem organizationally — you can't search people before a meeting and check whether the handsets are on or not. But a whole industry of technical means of blocking mobile phones has emerged. In Russia alone, a dozen companies are engaged in the production of such devices — including «Maskom», «Nelk», «Surtel», «Radioservis», «NERA-S». Products of foreign manufacture are also entering the country — products of the well-known Israeli company NetLine (blockers of the C-Guard series), blockers of Taiwanese companies (DLW2000-4000, RK-3000-6000, SH-066PL, etc.). It is important to note that the overwhelming majority of devices presented on the market are active signal suppression equipment. Despite all the diversity, they operate on a similar principle of generating barrage interference in the entire frequency range of the phone, as a result of which the phone simply stops «seeing» its network. The main difference between blockers of this type is the signal power, which affects their range, and the number of blocked ranges, which together determines the cost of the products. The simplest devices cover only the GSM900/1800 range, others — no more than two ranges (GSM, CDMA800) and only the most advanced models can «boast» the ability to block phones operating in the CDMA2000, DECT and NMT450i standards. There are also differences in terms of ease of use of products from different manufacturers. Some models work only from the network, others have alternative power sources, are supplied with remote controls, are camouflaged as interior items, etc. And yet one of the most important indicators is the range. For the «weakest» models, it does not exceed 15 meters (the lowest-power, battery-powered, cover a zone of 2 — 3 meters). Powerful models, such as “Barkhan-3” and “Mosaic-ZM”, provide cellular coverage in a zone with a radius of up to 40 meters and have a total radiation power of up to 9 W. However, it is quite difficult to judge the real efficiency of a particular model based on the declared passport data. It is not for nothing that all manufacturers indicate that the range depends on the distance to the nearest base station. Well, if the blocker does not cover the entire room — it means the cell is close. Moreover, no one has yet conducted comparative field tests of products from different manufacturers in similar conditions (apparently, for reasons of corporate ethics).
The coverage area of the device does not depend on the proximity of the base stations, since it is determined not so much by the power of the blocking signal as by the sensitivity of the blocker receiver and the adjustment of the detection threshold of the cell phone signal. The blocker has an indication of the definition of the cellular communication standard and is designed for round-the-clock operation. In the standard package, «Ginger» is supplied with a broadband discone antenna. In another version, it is equipped with a new, unique, flat antenna with 5 resonances in all frequency ranges. This antenna allows you to make the device extremely compact and camouflage it, for example, under a small picture. An even more miniature portable version is also being developed. The pulse output power of the new blocker is at least 1 W, the blocking range is 10 — 20 m.
«NERA-S»
Address: Moscow, 109004, st. Bolshaya Kommunisticheskaya, 27, office 335
Phone: (7 495) 912-57-18, 103-04-49
http://nera-s
http://biotox.ru
E-mail: nera-s@rutenia.ru