What is long-range identification for? What tasks does it solve?.
Long-range identification is identification based on radio frequency identification (RFID) technology. When we talk about long-range identification, we are talking about reading tags at long distances. This can be 5-10 meters, and for some tasks, 50-100 meters.
One of the areas of application of long-range identification is security systems. Due to the large reading range, it is convenient, for example, to organize the entry of vehicles into the territory of enterprises. The driver does not need to reach for the reader with the card, the tag just needs to be in the car. However, in addition to use in access control systems, this technology can successfully find application in a number of other areas:
logistics;
control of movement on toll highways;
warehouse accounting;
container monitoring systems at storage sites, etc. In our country, this is still rather exotic, but in Western countries, the use of long-range identification on toll sections of highways is a common phenomenon. If everyone pays for a single trip, this will lead to large losses of time at the checkpoint. You can use a subscription for the required number of trips — such a subscription is a tag that can be read at a large distance and at high speed.
What can be said about the licensing of frequencies on which long-range identification works? And are combined tags harmful to health?
The Parsec long-range identification system operates in the 2.45 GHz range. With low radiated powers, this is an unlicensed range in which Wi-Fi networks operate. The Parsec long-range identification system can be used without permission to allocate a frequency range from the State Commission on Radio Frequencies (SCRF), since the maximum radiated power of the tags is several times less than the permissible limits.
The question: «Isn't it harmful to health to carry a tag in your pocket?» is one of the most frequently asked. Since the power is low and the tag does not emit constantly, we can say that it is completely harmless to health. Compared to a tag, a mobile phone has an order of magnitude greater effect on the human body.
How does the system work? What equipment is needed for full-fledged operation?
The system consists of a PR-G07 reader (electronics unit + 2 remote antennas) and ActiveTag tags, available in various designs — from key fobs to industrial sealed tags with an extended temperature range. The reader is made dual-channel, which essentially means 2 readers in one. That is, with the help of one PR-G07, you can service either one two-way entry point, or two one-way ones (if readers are needed only for entry).
The tag constantly issues its code at a set frequency. When it enters the antenna's field of action, the tag code is received by the reader and, depending on the programmed operating mode, can be transmitted to the outside world (to the access system controller, to the computer). The logic of the system reader is flexibly programmable, which allows adapting the operating modes to specific application conditions. For these purposes, a utility is supplied with the reader, allowing you to change various reader parameters.
As examples, we can cite two of the most frequently used modes of system operation.
A simple registration mode without obstructing devices is used in cases where it is necessary to determine the fact and direction of a vehicle's passage. The system is used in logistics, on toll roads, parking lots, etc. The mode in question, thanks to the use of 2 antennas, makes it possible to determine the direction of vehicle movement based on the sequence of intersections of antenna reading zones without using additional sensors. Stable reading of the tag is ensured when the vehicle is moving at a speed of up to 200 km/h, depending on the antenna used and its direction.
Full mode of operation with support for automatic sensors of the access point. A car with a tag, approaching the barrier, covers the IR barrier, which is directly connected to the system reader. In this case, the tag gets into the visibility zone of the reader's antenna. If it is recognized by the reader as «its own» (the reader can distinguish tag lot numbers and can ignore «foreign» tags, related, for example, to a neighboring object), then the tag code is transmitted to the controller that controls this point, which makes a decision to open the barrier. If a car with «its own» tag simply drove past without crossing the IR barrier, the tag code will not be transmitted to the controller and the barrier will not be falsely opened. Instead of an IR barrier, a weighing platform, an induction loop or any other device for detecting the presence of a car can be used. Having passed the barrier, the car gets into the visibility zone of the second antenna, which works on the exit. The tag will be read by this antenna in any case, but the code will not be transmitted to the controller, so that the controller does not receive an unnecessary paired event from the reader.
What can the system be connected to?
When it comes to security systems, PR-G07 readers can be connected not only to the controllers of the integrated ParsecNET system, but also to almost any other controllers, since they have Parsec interfaces and the most common Wiegand 26 and Touch Memory.
In addition, to use the system in various third-party applications, the reader has an opto-isolated RS-485 interface, which allows you to connect up to 30 such devices (the readers support addressing) to one communication line. An interesting example of such use of the system is the personnel accounting and location system developed for coal mines, where the readers are mounted on a single RS-485 loop at various points in the mine, and the tags are attached inside the helmet-lamp.
To integrate readers into customer applications, a developer's kit (SDK) is available with the necessary libraries (DLL), examples of their use and documentation.
What are the key differences between the Parsec long-range identification system and similar systems?
The main differences include the following.
Dual-channel implementation of the reader. This allows organizing various modes of operation of the access point with filtering in the reader itself of «extra» repeated events that interfere with the operation of the ACS controllers, having the ability to implement identification of transport both at entry and exit using one reader, register the direction of movement of cars without additional devices, etc.
The use of external antennas makes it possible, if necessary, to select antennas with the desired directional diagram, sensitivity, mounting method, and appearance for installation in a specific situation.
A unique anti-collision mechanism allows the reader to simultaneously «see» up to 64 tags in the antenna's field of action.
The programmable frequency of code output by the tag allows for a significant increase in the service life of the battery if there is no need to output the code too often (a high frequency of code output may be needed only in rare cases when the object with the tag is moving very quickly). At the same time, the design of the tags allows for easy replacement of batteries (one of the most common types of batteries is used) directly on the site.
Additional information on the capabilities and features of the system can be found on the website parsec.ru