Study Of Chipless UWB-RFID Technology

As an emerging automatic identification technology, RFID technology has manymerits, such as durability, compact size, large capacity, reusability and so on. Combinedwith the internet and communication technologies, it can trail commodities and shareinformation across the world. RFID technology, which can be applied to more areaswith the development of technology, has now become one of the hot research fields andwill embrace a bright market outlook.However the tag cost, especially the chip cost, is a bottleneck for the sweepingapplication of RFID technology. Recently, chipless RFID tag has been proposed, whichprovided idea for the large cost. Under such background, this paper presents a design ofan ultra wide band chipless RFID tag and the correspondent gaussian pulse generator.The main content includes the following aspects:1. The first part is a discussion of RFID system and how it works followed by abrief introduction of the types of chipless RFID tags that have ever existed.2. The second part introduces the design of a RFID tag based on time delay andphase code. The tag is composed of five UWB coplanar waveguide antennas traced withdelay lines, each of which is followed by three kinds of loadings. When the tag isstimulated by an UWB narrow pulse, a series of scattering pulses return with differentphase information and delay time, the modulation of the backscattered signals is thencompleted. With varied phases of the backscattered signals at different time, every taghas their own ID.3. The last part presents a design of Gaussian pulse generator with the analysis ofseveral UWB pulse generation technologies. Consisting of the core component,ordinary RF triode, and other components like electric resistance, capacitance andinductance, this kind of pulse generator can generate narrow pulse in the way ofcapacitor charging and discharging by the utilization of the triode’s switching feature.