Views:5 Author:Site Editor Publish Time: 2018-01-04 Origin:Site
People are confusing with the difference between the passive RFID tag and active RFID tag, especially when they choose tags for their system and create their own system solution. So what is the actual difference and how to choose the proper one and used for your application?
This article has talked about the main difference by the composition, the application and the cost.
Passive RFID Tags
Passive RFID tags are comprised of three elements: an integrated circuit or chip, an antenna, and a substrate.
The RFID chip stores data and performs specific tasks. Depending on its design, the chip may be read-only (RO), write-once, read-many (WORM), or read-write (RW). Typically, RFID chips carry 96 bits of memory but can range from 2-1000 bits.
Attached to the RFID tags chip is the antenna, whose purpose is to absorb radio-frequency (RF) waves from the reader's signal and to send and receive data. Passive RFID tag performance is strongly dependent on the antenna's size: the larger the antenna, the more energy it can collect and then send back out. Larger antennas, therefore, have higher read ranges (although not as high as those of active RFID tags).
Antenna shape is also important to the performance of the RFID tag. Low-frequency and high-frequency (LF and HF, respectively) antennas are usually coils because these frequencies are predominantly magnetic in nature. Ultrahigh-frequency (UHF) antennas, on the other hand, look similar to old-fashioned TV antennas (“rabbit ears”) becauseultrahigh frequencies are solely electric in nature.
The third component of a passive RFID tag is called substrate, which is commonly a Mylar or plastic film. Both the antenna and the chip are attached to the substrate, which may be thought of as the “glue” that holds all of the RFID tag's pieces together.
In contrast to active RFID tags, passive tags are usually smaller and less expensive.
Active RFID Tags
Like passive RFID tags, active tags have both a microchip and an antenna. The chips, however, are usually larger in size and have greater capabilities than the RFID chips in passive RFID tags.
Active RFID tags have two additional components that differentiate them from passive RFID tags: an on-board power supply and on-board electronics.
The power supply is usually a battery, although it can also be solar. The built-in power supply allows the RFID tag to transmit data to a reader on its own, without the need to draw power from the reader itself like passive tags do. In addition, active tags can be read from distances of 100 feet or more, whereas passive tags can only be read from up to about 20 feet.
On-board electronics may consist of sensors, microprocessors, and input/output ports, all of which are powered by the tag's on-board power source. The electronics allow active RFID tags to be used in a wider range of applications than passive tags. For example, perishable food products may be tagged with sensors that collect data that can then be used to determine expiration dates and warn the end user that the item may be spoiled. Even though many products have expiration dates printed on them, these dates are valid only if the product is stored under the optimal conditions (temperature, humidity, exposure to light, etc.) for that type of product. Thus, the product may expire before the printed date if it is not stored properly. An RFID tag equipped with a temperature sensor might be able to predict the actual expiration date of a carton of milk, for example, which may be very different from the printed date.
Whether you choose to use active or passive RFID tags in your RFID system will likely depend on both your particular application and your budget. Simple asset tracking that utilizes barcode technology will become obsolete as RFID proliferates through organizations, making them more efficient and better equipped for accuracy.
After reading the above information, you must have obtained some method to distinguish the difference and select your RFID tags. As a professional China RFID tag supplier, we provide worldwide customers with a variety of RFID products, such as RFID cards, RFID tags, NFC tags, etc.. You can browse our classification of the products to choose what you want.