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Radio technology in the field of automatic identification applications, more specific name for the radio frequency identification technology, English as Radio Frequency Identification, referred to as RFID . The composition of radio frequency identification systems generally include at least two parts: (1) Tag The English name for the Tag; (2) readers, the English name for Reader. Tag in the agreed format for the general preservation of electronic data, in practice, the electronic tag attached to the surface of the object to be identified. Reader device, also known as read, be read without contact and identification tag stored in the electronic data, so as to achieve the purpose of automatic identification of objects. Further through the computer and the computer network to realize the object recognition information collection, processing and management features such as remote transmission. Radio Frequency Identification RFID technology according to the classification of different frequencies used in the system can be divided into low and high frequency system of two categories; according to whether the electronic tag with Battery Its power, can be divided into active systems and two types of passive systems; from the information stored within the electronic label injection method may be the sub- IC Curing type, site type and field of wireless cable rewrite rewrite type three categories; read tag data, according to technology tools, can be divided into Broadcasting Launch Type, Frequency modulation type and reflection type three categories. 1. Low-frequency systems generally refers to the operating frequency less than 30MHz, the typical working frequency: 125KHz, 225KHz, 13.56M, etc., based on the frequency of the radio frequency identification system generally have corresponding international standards. The basic features of lower-cost electronic tags, labels, less the amount of data stored inside, reading a short distance (passive case, the typical reading distance of 10cm), electronic tag shape diversity (card-shaped, circular, button-like , pen-like), reading non-directional antenna and strong. 2. High frequency systems generally refers to the frequency greater than 400MHz, the typical working band: 915MHz, 2450MHz, 5800MHz and so on. High-frequency systems in these bands also have a large number of international standards to support it. The basic features of high-frequency system, the electronic tag and reader costs are high, the tag stored data volume, reading distance (up to ten meters a few meters) to meet the object high speed performance, appearance is usually card shaped antenna and electronic tag read had strong directional antenna. 3. Active electronic tag that has the battery, and generally has far reading distance, inadequate battery life is limited (3 to 10 years); Passive electronic tags without batteries, it receives reader ( read out device) to issue the microwave signal, part of the microwave energy into direct current for their own work, general maintenance can be achieved. Compared to active systems, passive systems, and adapt to the movement of objects to read from a slight speed limit. 4. Integrated curing electronic tag information in general about the information in the IC production process model with ROM into its stored information is static; live cable adapted electronic tag will generally be stored tag information is written its internal storage area rewrite E2 need a dedicated programmer or a writer, rewrite the process to have their power supply; site wireless rewritten electronic tags are generally applicable to active electronic tag, with a particular rewrite instructions, electronic tag information is also stored in storage area in which the E2. General rewrite of electronic tag data read time is much greater than the time required for tag data. Typically, the time required for the second-level rewritten, reading time is millisecond. 5. Radio transmission Radio Frequency Identification easiest to achieve. Tag must be active approach to work and to be stored in real time Logo Information outside broadcasts, readers not only cost the equivalent of a hair receiver. The disadvantage of such systems because the electronic tag information to be kept out firing both electric charge, then electromagnetic pollution on the environment, and the system does not have Security Confidentiality. Frequency Radio Frequency Identification systems have some difficulties to achieve them. In general, reading signals emitted by radio frequency queries, electronic tag return signal carrier frequency of radio frequency multiplier reader. This mode of receiving and processing of the echo signal reader provides a convenient, however, passive RFID, the electronic tag reader to receive radio frequency energy is converted to harmonic echo carrier frequency, its energy conversion efficiency than low conversion efficiency, it requires a high microwave techniques, which means higher cost of RFID tags. At the same time such a system work to occupy two working frequencies, generally more difficult to obtain radio frequency licenses Application Management Committee. Reflex modulation radio frequency identification system to achieve up to solve the problem with the frequency transceiver. Systems work, read the microwave emitted by check (energy) signal, the electronic tags (passive) part of the received microwave energy signal rectifier query electronic tags for the DC circuit for the work, another part of the microwave energy signals are stored within the electronic tag The data modulation (ASK) and then reflected back to reader. Reader receives the signal reflected back to the amplitude modulation, the solutions of the electronic tag from the logo of the saved data. System during the work, reading and receiving microwave signals emitted by the amplitude modulation signal reflected back is parallel. Reflected back into the signal strength is much weaker than the transmitted signal, so the difficulty lies in technology to receive the same frequency. [Key words]: Radio Frequency Identification System RFID Comment Large In Small I am an expert from flexibleledstriplights.com, while we provides the quality product, such as Special LED Light , Spiral Energy Saving Lamp, Flexible LED Strip Lights,and more.
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