The Research And Implementation Of RFID Reader In UHF Band

Radio Frequency Identification(RFID) is one of the non-contact automatic identification technologies which can realize intercommunication by using wireless channel. Ultra high frequency(UHF) RFID technology is the international study hot spot, which has advantages of long identification distance, speedy identification, relatively long life, etc. And it will be applied to these domain Logisties Management, Strategyand tracking of Products and Freeway charge. Therefore, the research of UHF RFID reader has a very important practical significance.The paper on the basement of a wide range of access to information, study of the UHF band protocol ISO/IEC18000-6 detailly, analyze the existing feasible program design, simulate and analysise of the program. Then this paper give a system design of reader program ,verify and improve the method in the project. As an engineering study of the subject, base on the absorption of existing technology ,do some new attempts and explorations, adopte the integrated radio frequency transceiver chip AS3990 and ultra-low-power microprocessor MSP430F157 to reduce the power consumption and volume of reader.In hardware design, It selectes MSP430F157 as the main controller, constitutes a master, communications, power control circuitry. And developes the AS3990 constitutes radio frequency transceiver module design, as AS3990 only integrates ISO/IEC18000-6C protocol, in the realization of ISO/IEC18000-6B protocol, using AS3990 to achieve radio transceiver transfer, modulation and demodulation functions, using baseband software to achieve coding and decoding functions.In software design, It adoptes modular and structured programming ideas, programming language using C. Include the main, protocol processing, communication and anti-collision procedures. The main program is charge for system dispatch, protocol processing procedures are charge for protocols command processing, communications handler is charge for communicating with the host, the anti-collision procedures accomplish the binary trees and ALOHA algorithm.This design with low power consumption, modular, compact design features, reaching ISO/IEC18000-6B/C protocols call for, performance of stable and reliable.