the new application of the active RFID of human and goods timely positioning system
2.45G active RFID tags (card) is a new kind of technology in the field of RFID application. Because this kind of electronic tags transmit power is very low, and the air of wireless data transmission distances of up to one hundred meters, and the external environment on the transport properties, beginning in the RF fields obtained user great attention. With the application of data people for 2.45G active radio frequency electronic tags in a limited range of personnel management and logistics and distribution, warehousing and transportation, vehicle access management the system can through short message platform or transmitted on the Internet, more make the product shows an extremely wide application prospect.
With the popularization and application of 2.45G active RFID tag, people find this kind of electronic tags (card shape packaging a variety of different applications) characteristics are much better than other RFID products. If this kind of electronic label sensing direction of change is not obvious, if this kind of label is attached on the surface of the metal, the influence is relatively small, such labels can also be made read-only and read-write type. If the use of special data anti conflict reading sensor, also can be read more than 100 pieces of labels in a short period of time at the same time. In the application of 2.45G electronic tags in the process, the people to the product of the perfect pursuit is endless. For example, in the management of a small range of personnel flow time (such as a hospital inpatient, kindergarten and so on), managers sometimes not only to know the time at which the tag reading sensor reading, but also want to know at the moment the label where near moving (XN, YN), at this time the label in the coordinates of the location of the original set of. The substantial requirement is: require such labeling with spatial positioning function. So you can make the specific location of passive management and storage and transportation of small range of activities of the goods timely provide reliable location information to the management system, and bring great convenience for the management work.
Positioning function to achieve 2.45G electronic tag, the system in addition to the data processing part, reading recognition part and the electronic label, address code generator system must have a very wide distribution, function is relatively simple, the cost is low. When wearing the label for personnel to enter the location area, electronic label received sent address code generator address code, will soon address code and tag the original ID number is sent to the reading sensor, data transmission sensor read after treatment to the control system. Through the electronic map can always know the worn electronic label personnel the moment in which position. Of course, this time if someone is equipped with a handheld PDA type reading sensor, and is positioned is the electronic tag storage system of containers, you can connect to the PDA through a PDA or computer network, also can know the specific location of the cargo.
In view of this, the system adds a address code generator, is essential for locating RFID system equipment. Its main function is to transmit through programmed address code and to the electronic tag, and at the same time to tag will address code and label ID launch out. The realization of this function is the key to the use of what kind of frequency to transmit the address code. After repeated research, experiment, comparison, found that there are a variety of frequency can be achieved. A low frequency (LF) band, commonly used with 125K ~ 134K. High frequency (HF), commonly used with 433M ~ 445M. And the ultra high frequency (UHF) band, and even microwave frequency. By using the low frequency carrier as address code transmission, low frequency large power consumption and large volume of equipment, the distance can be more accurate, but the electronic tag identification address code has obvious directivity, will affect the use. Using the high frequency UHF as the transport address information carrier, the address range is big, not easy to precise positioning. At the same time as if receiving electronic tag will be greater, and is not suitable for popularization and application in large area.After comparison and practical application, with more than 2G frequency as the address signal transmission frequency. Direction of the electronic label is not obvious, the distance is accurate, and the size and cost of electronic tag is not too high, relatively broad application prospects. Now the RFID real time location system has been in the hospital, school, prison underground and many fields in small quantities used, and has shown its great potential application. In order to address the boundary crossing problem of electronic tag system developers have a variety of different methods to solve. Such as increasing the anti accentuation address code, after repeated many remain no longer transmission, when only the change of address code and re evaluation of electronic label position, even when tag from the boundary address will send the alarm signal is sent to the guard on duty location.
Increase the security personnel and goods to care..
Relatively passive radio frequency electronic tags, 2.45G active electronic tag cost is relatively high. But due to the excellent performance of 2.45G active electronic tag, and successfully applied in many fields has achieved good economic and social benefits, far more than the former. We have reason to believe that the 2.45GRFID real time location system has a more broad application prospects.