Electronic article surveillance - antennas and functions

 

Our article protection systems are delivered – according to the system – with different antennas which have certain qualities and functions. These antennas are:

 

An active antenna – mono antenna is at the same time a broadcasting and a receiver’s antenna. It sends out the signal and can also identify – due to the powerful processor – the interference signal. Active antennas are always used in mono antenna systems, as they always have to perform both tasks.

 

The protection of merchandise with a mono antenna is the easiest form of the article protection. These antennas can protect entrance areas up to 120 cm in both directions. If this antenna is installed in the middle of the entrance area, an area up to 240 cm can be protected with a single mono antenna.

 

Nevertheless, the usual installation of mono antenna systems is on one side of the entrance area. Especially smaller boutiques or retail stores have less space and smaller entrance areas which can be protected with one antenna installed on the side. It is to be noted that the mono antennas still send out signals in both directions. Therefore, the articles placed on the "dead" side of the system may not be protected with tag or labels.

 

 

Passive antennas are on its own no article surveillance systems, however, passive antennas still fulfill two important tasks in the article protection.

 

Passive antennas are used primarily where the protection area with a mono antenna is too wide. The passive antennas contain no active surveillance electronics. However, the wiring within this antenna is required to strengthen the core signal within the detection range. The passive antenna is connected merely with the antenna cable of the mono antenna, no special power supply is needed. With a mono-passiv system you can protect entrance areas up to 160-180 cm easily. Another beneficial aspect is that also the radiation of the antennas is reduced by this kind of the system. Therefore, it is possible to place protected articles closer to the antennas.

 

Our article protection systems are so powerful that two passive antennas can be combined with a single mono antenna. Therefore an entrance area of 320-360 cm can be protected with only one article protection electronics.

 

The second application is the usage as a pure dummy. Here the shopkeeper trusts exclusively in the deterrent effect of the antenna hoping to keep shoplifters away.

 

 

Article protection systems with 2 antennas are the classic systems for the protection of retail stores and boutiques.

 

These systems have an active transmitter and an active receiver. The transmitter antenna only sends out the signal, the receivers´ task is to receive the interference. Thus the transmitter antennas can send out more intensive signals in a higher frequency density, receiver’s antennas can conceive more sensitively and more intensely. Due to the separation of tasks, the detection quality is increased and the possible protection area is enlarged.

 

The distance which can be protected with an antenna system 2 is depending on the used hard etiquettes, tags and security labels. It is a rule of thumb that the bigger the tag is, the larger is also the detection area and quality.

 

 

The system EAS Easydet corresponds in the concept to the system of the dual system Superdet, however, with slightly other qualities. Basically one can say that these antennas are less powerful but more favourable.