What Is An RFID ?

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RFID tags can be divided into three different categories according to the power supply method , passive RFID , active RFID, and semi-active RFID.

1，Passive RFID

Passive RFID is the most widely used in RFID filed that also is the earliest and the most mature among the three types of RFID products. In passive RFID, the electronic tag receives the microwave signal transmitted by the radio frequency identification reader and obtains energy through the electromagnetic induction coil to temporarily supply power to itself, thus completing this information exchange. Because the power supply system is omitted, the volume of passive RFID products can reach the order of centimeters or even smaller, and the structure is simple, the cost is low, the failure rate is low, and the service life is long. But as a price, the effective identification distance of passive RFID is usually short, and it is generally used for close contact identification. Passive RFID mainly works in the lower frequency bands 125KHz, 13.56MKHz, etc. It widely used in bus cards, Identity ID cards etc.

2, Active RFID

Active RFID has not been around for a long time, but it has played an indispensable role in various fields, especially in highway electronic toll collection systems. Active RFID is powered by an external power supply and actively sends signals to radio frequency identification readers. It’s volume is relatively large. But it also has a longer transmission distance and higher transmission speed. A typical active RFID tag can establish contact with an RFID reader 100 meters away with a reading rate of 1,700 read / sec.

Active RFID mainly works in higher frequency bands， such as 900MHz, 2.45GHz and 5.8GHz, and it has the function of identifying multiple tags simultaneously. The long-range and high efficiency of active RFID makes it indispensable in some radio frequency identification applications that require high performance etc.

3，Semi-active RFID

Passive RFID itself does not supply power, but the effective identification distance is too short. The active RFID identification distance is long enough, but requires an external power supply, which is large. The semi-active RFID is the product of compromise for this contradiction. Semi-active RFID is also called low-frequency activation trigger technology. Under normal circumstances, semi-active RFID products are in a dormant state and only power the data retention part of the tag, so the power consumption is small and can be maintained for a long time. When the tag enters the identification range of the radio frequency identification reader, the reader first activates the tag accurately in a small range with a low frequency signal of 125KHz to make it enter the working state, and then transmits information with it through the 2.4GHz microwave. That is to say, first use low-frequency signals to accurately locate, and then use high-frequency signals to quickly transmit data. Its general application scenario is: in a large area covered by a high-frequency signal, multiple low-frequency readers are placed at different positions for activating semi-active RFID products. This not only completes the positioning, but also realizes the collection and transmission of information.

What's the  different features ？

Generally speaking, RFID technology has the following characteristics:

1. Applicability: RFID technology relies on electromagnetic waves and does not require physical contact between the two parties. This allows it to establish a connection regardless of dust, fog, plastic, paper, wood, and various obstacles, and directly complete the communication.

2. High efficiency: The reading and writing speed of the RFID system is extremely fast, and a typical RFID transmission process is usually less than 100 milliseconds. The high-band RFID reader can even recognize and read the contents of multiple tags at the same time, greatly improving the efficiency of information transmission.

3. Uniqueness: Each RFID tag is unique. Through the one-to-one correspondence between RFID tags and products, you can clearly track the subsequent circulation of each product.

4. Simplicity: RFID tag has simple structure, high recognition rate and simple reading equipment. Especially as NFC technology is gradually popularized on smart phones, each user's mobile phone will become the simplest RFID reader.

Advantage

RFID technology can be widely applied to many industries and fields, and it must have its "excellent".

In terms of its external manifestations, the carrier of RFID technology is generally to have the characteristics of waterproof, anti-magnetic, high temperature resistance, etc., to ensure the stability of RFID technology in application. In terms of its use, RFID has advantages in real-time updating of data, amount of stored information, service life, working efficiency, security, etc. RFID can update the existing data more conveniently and reduce the manpower, material and financial resources, making work more convenient,  RFID technology stores information based on computers, etc., up to several megabytes, and can store a large amount of information . To ensure the smooth progress of the work,

RFID technology has a long service life, as long as the staff pays attention to protection during use, it can be reused; RFID technology has changed the inconvenience of information processing in the past, achieving multiple goals simultaneously Identification greatly improves work efficiency; while RFID is also provided with password protection, it is not easy to be forged and has high security. The technology similar to the radio frequency identification technology is the traditional bar code technology. The traditional bar code technology is inferior to the radio frequency identification technology in updating data, storing information amount, service life, working efficiency, security, etc., and cannot adapt well . The current social development needs are also difficult to meet the needs of industry and related fields.

Disadvantages

(1) The technology is not mature enough: RFID technology has been around for a short time and is not yet very mature in technology. Because UHF RFID tags have the characteristics of retroreflectivity, it is difficult to apply them to commodities such as metals and liquids.

(2) High cost: The price of RFID tags is higher than that of ordinary barcode tags, which is dozens of times that of ordinary barcode tags. If the amount of use is large, the cost will be too high, which greatly reduces the market's enthusiasm for using RFID technology.

(3) The security is not strong enough: The security problems faced by RFID technology are mainly manifested in the illegal reading and malicious tampering of RFID label information.

(4) The technical standards are not uniform.

Example of Applications：

Examples of applications that benefit from RFID are endless. Applications extend from broad areas like inventory tracking to supply chain management and can become more specialized depending on the company or industry. Types of RFID applications can span from IT asset tracking to textile tracking and even into specifics like rental item tracking.

1、Race Timing
2、Supply Chain Management
3、Pharmaceutical Tracking
4、Inventory Tracking
5、IT Asset Tracking
6、Laundry & Textile Tracking
7、File Tracking
8、Returnable Transit Item (RTI) Tracking
9、Event & Attendee Tracking
10、Access Control
11、Vehicle Tracking
12、Tolling
13、Hospital Infant Tracking
14、Animal Tracking
15、Tool Tracking
16、Jewelry Tracking
17、Retail Inventory Tracking
18、Pipe and Spool Tracking
19、Logistics Tracking (Materials Management)
20、DVD Kiosks
21、Library Materials Tracking
22、Marketing Campaigns
23、Real-Time Location Systems