Since 2004, 4g cell phone jammer with the RFID technology related articles continue to emerge in various media, relevant reports make this history is not short of technology in a short time become the focus of an international chase. From a global business empire giant Wal-Mart, the international lT giants IBM, HP, Microsoft, etc., from the United States Department of Defense to China National Standards Committee, all under the command of RFID wand dance together. So what exactly is how RFID will have so much charm to let the world so crazy that we look at such a report:?? http://www.4gcellphonejammers.com/
Western side of the Rhine in Germany, a city named Noyes, a customer is a large supermarket METRO shopping before, when he selected things to buy, leisurely walked electronic automatic pay machines, neither the cashier checkout queued as before, and without the trolleys of goods one by one out, let the salesperson for each commodity barcode scan, he was just a short stay for a few seconds, you push a shopping cart and walked out of the supermarket. 4g cell phone jammer This occurred in the Metro supermarket scene sounds like a very fresh, like a science fiction movie, fictional things, actually seven, before long, it will happen in real life around us. This is RFlD-- radio frequency identification technology to change our lives.
Meaning 1 RFID's
Radio Frequency Identification RFID is an abbreviation that radio frequency identification. It is a non-contact automatic identification technology, automatic target recognition through radio frequency signals and access to relevant data, without human intervention, can work in a variety of harsh environments. RFID technology can identify fast moving objects can also identify multiple tags, easy to operate.
2 RFID composition and working principle
RFID system consists of electronic tags (Tag), reading ditch device (Reader), antenna (Antenna) components.
Electronic tags (Tag): the coupling components and chips, each tag has a unique electronic code, attached to the object to identify the target object.
Reader (Reader): also known as reading means, and can be read without contact the identification tag stored in the electronic data, so as to achieve the purpose of secretion of other objects automatically, with two hand-held or fixed, are usually read is connected to the computer, read the label information is transferred to a computer for further processing.
Antenna (Antenna): asked to pass RF signals in tags and readers
Since the PLC technology such cattle, as long as the wire erected where, where data communications can be transmitted, then why do not we use the Internet PLC power line technology in daily life, instead of using ADSL, optical fiber, etc., as broadband access it? This is due to the inherent disadvantages of PLC technology limit its wider application. 4g cell phone jammer
1 distribution transformers for power line carrier signal has a blocking effect, so the power of the carrier signal can only be transferred within the region of a distribution transformer;
2 electronic line carrier signal attenuation great, it is generally only a single power line carrier signal phase power line transmission;
Electrical apparatus according to many of the power line, the carrier signal will cause interference, and interference signal power may be far greater than the carrier signal.
In conclusion, is not an ideal medium for the power line carrier signal transmission, so the PLC carrier technology has been limited to applications like remote meter reading. But with the Internet communications of smart grid construction, smart home appliances, smart meters between the PLC carrier technology and provide a new arena, and major manufacturers for the PLC-carrier technology is constantly improved to make it more suitable for data transmission and communications.
The main PLC carrier technology
At present, the domestic carrier communication basically narrowband FSK carrier, in this way by the power line loads greater impact, the communication channel is likely to cause instability, and its propagation rate is not enough, not up to the requirements of real-time communication smart meters, so a lot of new the carrier communication improvement program came into being.
Such as the S-FSK and ASK modulation Semiconductor uses automatic switching technology, STMicroelectronics used n-PSK modulation, and the United States believe in the main push of PLC-G3 scheme, based on OFDM modulation technology, as well as the Middle East and Europe are deploying the PRIME standard, also based on OFDM modulation techniques. Major semiconductor manufacturers for each technique also has a corresponding chip solution launch, such as Maxim's MAX2990, MAX2992, STMicroelectronics ST7580, etc., and TI's C2000 DSP platform solution is used, the user can simply modify the software agreement achieve a variety of standard solutions FSK, G3, PRIME, etc., for the design brings great convenience. 4g cell phone jammer
With the deepening of smart grid development, I believe PLC carrier technology will certainly be more widely used, and with continuous improvement and evolution of the technology, it will be more deeply into our lives, changing the our way of life.
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