In parallel with the advantages that the NFC functionality of credit cards offers to the customers, some weak points, which can be used by criminal subjects for money (information) theft, exist. In the crowds, trams, trains, queues..etc., criminals can easily, simply holding their NFC devices close to the wallet (pocket, bag) of the offer, scan and extract the data of the credit/security/health insurance/ID cards and after that use it for criminal acts. I have invented a simple and secure solution to solve the mentioned problem.

The patent application "NFC jammer" is filled and registered under the identifier EP12195187.

The invention concerns a NFC jammer device used to protect NFC eligible devices (credit cards, identity cards, secured entrance control cards, health insurance cards … etc.) from hacker attacks and stealing their information. It can be embedded inside credit card size plastic cards, in the wallet or hand bags walls, suit pockets and everywhere, where the mentioned electronic documents can be stored (carried).

The object of the present invention is to provide a NFC jammer with high efficiency, small size and fully complaining the radio emitting regulations protecting the other NFC cards from stealing the internal information.

The proposed NFC jammer fully satisfies the defined above requirements. The jammer is placed nearby the victim NFC device. It senses the same electromagnetic field used from
the attacker to read the NFC card. It is supplied by the same field as the attacked NFC device and transmits data simultaneously with the victim NFC device. Thus the sent data from both devices interfere and its decoding is impossible.

The NFC jammer comprises receiver/transmitter resonance loop. The loop is connected to PMU (power management unit) used to supply all other blocks of the jammer with energy.
The PMU supplies a RPG (random/quasi-random pattern generator with embedded internal oscillator). The RPG output is connected with the input of NFC modulator supplied by the
PMU. The output of the NFC modulator is connected with the input of Power amplifier, also supplied by the PMU. For more complete description of the present invention and its advantages, reference is made to the following description, taken in conjunction with the accompanying drawing (Fig.1), in which the architecture of the NFC jammer with the internal interconnections is shown. An embodiment of the invention is presented in Fig.1.

The principle of work of the proposed invention is as follows: The NFC jammer shall be placed always in close distance to the NFC electronic document, which must be protected. When unsolicited attempt for the reading of the information of the electronic document happens, both the electronic document and the jammer start to send the data simultaneously – the electronic document (credit card) its own data; the jammer – randomly generated dummy data. Both data flows interferer, what corrupts the NFC data transfer protocol and the data kept in the electronic document remains unread and safe against the hacker attack.