RF low noise amplifier circuit
RF refers to with a certain wavelength for electromagnetic wave radio communication. The high frequency circuit used to generate radio frequency is a radio frequency circuit, consisting essentially of passive components, active devices, and passive networks. With the development of communication technology, the frequency of communication equipment is increasing day by day. Radio frequency (RF) and microwave (MW) circuits are widely used in communication systems. The field of RF circuit design has received special attention in industry.
RF (Radio Frequency) technology is widely used in many fields, such as television, radio, mobile phone, radar, automatic identification system and so on. Special term RFID (radio frequency identification) means the identification of objects by means of radio frequency identification signals. Including the application of RFID: ETC (Electronic Toll Collection), railway vehicle recognition and tracking, container identification, valuables identification, authentication and tracking, retail, healthcare, logistics services, target management, and access control, animal identification and tracking, automatic vehicle lock (Security)
RF (radio frequency) refers to having a wavelength can be used for electromagnetic wave radio communication. The electromagnetic wave can be represented by its frequency as KHz (kHz), MHz (MHz) and GHz (Qian Zhaohe). Its frequency range is VLF (extremely low frequency), that is, 10-30KHz to EHF (extremely high frequency), that is, 30-300GHz. RFID is an easy to handle, simple, practical and flexible application technology especially suited for automatic control. Its unique advantages are unmatched by other identification technologies. It can support read only working mode, also can support read-write mode, and do not need to touch or aim at. It can work freely in all kinds of bad environment, and can carry on the high data integration. In addition, because the technology is difficult to counterfeit and intrusion, the RFID has a high security protection capability.
Conceptually, RFID is similar to the bar code scanning, the bar code technology, it will have a bar code encoding attached to the object and use the special scanning reader using optical signal will be transmitted to the magnetic strip information by scanning the reader; and the RFID is used for the RFID reader and can be attached to the target of RFID special unit, using the RF signal information by RFID unit sent to the RFID reader. Contains all relevant information about the target in the RFID unit such as the name of the object, the target location, the location of the transfer transport initiation termination and the target after a specific time, but also can load such as temperature index. The RFID unit, such as labels, cards can be flexibly attached to the radio frequency from the vehicle to the various items of RFID technology used for truck chassis 50KHz-5.8GHz, as shown in Figure 1, one of the most basic RFID system generally include the following parts:
An object containing information related to the RFID unit (answering machine or card, label etc.); the reader and the RFID unit of RF signal transmission antenna; a RF signal generated by the RF transceiver (RF transceiver); a received RF signal returned from the RFID unit and the decoded data transmission to the host system for processing the reader; reader, antenna, transceiver and host can be partially or fully integrated as a whole, or integrated into a small number of components. Different manufacturers have different integration methods.