Proximity cards – the way is open.

A plastic contactless card operating using Proximity technology at frequencies of 125 and 62.5 kHz. Proximity cards are made of light-colored polycarbonate. They have compact dimensions, usually no more than 85.7x54x1.8 mm, which makes it convenient to store such a «key» with you. On one of the surfaces of the proximity cardhave an individual factory number. The peculiarity of such a key, which allows passing through the reader, is the presence of a special sticker. The proximity card sticker is also a carrier of information about the company or a specific person. The card can be attached to clothing elements, for which there are special horizontal or vertical ones, through which a clip or strap is threaded. Proximity cards can be classified as universal elements of access control systems, since they have the ability to interact with street and indoor readers, as well as with readers of access cards to computer networks. Proximity cardsare representatives of the passive class, since they do not have a built-in power source. If we consider the device of the card in more detail, then each of them consists of two plastic plates, between which an antenna and a miniature chip are placed, and the plates are hermetically glued in factory conditions. The chip includes a transmitter, a receiver and a processor, in the memory of which the identification code of the card recorded at the factory is stored. Reading and recognition of code information from the card occurs on the basis of contactless radio frequency identification technology. Proximity cards work at a distance, with undemanding precision positioning of the object, which guarantees their stable and long-term service.

Proximity readers

Open or closed access in systems based on proximity technologies is provided by proximity readers. The operating principle of such a system is simple and also refers to the type of contactless autonomous access control systems. Proximity readers are designed to receive and identify code information from the card for the purpose of further transmitting this information to the access system controller. Proximity readerswork on the following principle: with the help of an inductance coil built into the reader mechanism, an electromagnetic field is created around the entire device. The same coil is located inside the proximity card. If, when passing through the access control system, the card is in the reader's field coverage area, an electric current is generated in its own coil, which provides power to the card's microcircuit. Then, when the microcircuit receives sufficient power from the electric field, it transmits the unique serial number sewn into it to the reader through the card coil. Proximity card readers, having captured and recorded the card's serial number, transmit it to the controller via the connection interface. Small readers with a long card reading distance are made in a plastic case. Proximity readers can work in sub-zero temperatures, and even in conditions of 100% humidity. Proximity card readers are characterized by various capabilities in terms of reading range. It depends on the reader circuit, the size of its antenna (inductor coil), the operating frequency, and also on the type of proximity card.