摘要：This paper presents a fully integrated passive UHF RFID tag chip complying with the ISO18000-6B *** tag chip includes an RF/analog front-end,a baseband processor,and a 512-bit EEPROM *** improve power conversion efficiency,a Schottky barrier diode based rectifier is adopted.A novel voltage reference using the peaking current source is discussed in detail,which can meet the low-power,low-voltage requirement while retaining circuit *** of the analog blocks are designed to work under sub-1 V to reduce power consumption,and several practical methods are used to further reduce the power consumption of the baseband *** whole tag chip is implemented in a TSMC 0.18μm CMOS process with a die size of 800×800μm;. Measurement results show that the total power consumption of the tag chip is only 7.4μW with a sensitivity of -12 dBm.

摘要：A fully integrated passive UHF RFID tag complying with the ISO 18000-6B protocol is presented, which includes an analog front-end, a baseband processor, and an EEPROM memory. To extend the communication range, a high efficiency differential-drive CMOS rectifier is adopted. A novel high performance voltage limiter is used to provide a stable limiting voltage, with a 172 mV voltage variation against temperature variation and process dispersion. The dynamic band-enhancement technique is used in the regulator circuit to improve the regulating capacity. A rail-to-rail hysteresis comparator is adopted to demodulate the signal correctly in any condition. The whole transponder chip is implemented in a 0.18μm CMOS process, with a die size of 900 × 800 μm2. Our measurement results show that the total power consumption of the tag chip is only 6.8 μW, with a sensitivity of -13.5 dBm.

摘要：We design a novel X-ray image detector by lens coupling a Gd2O2S：Tb intensifying screen with a high performance low-light-level （L^3, which often means luminescence less than 10^-3 Lux） image intensifier. Different coupling effects on imaging performance between zoom lens and fix-focus lens are analyzed theoretically. In experiment, for designing a detector of 15-inch visual field, the system coupled by zoom lens is of 12.25-lp/cm resolution, while the one with fix-focus lens is 10 lp/cm. The superiority of zoom lens is validated. It is concluded that zoom lens preserves the image information better than fix-focus lens and improves the imaging system＇s performance in this design, which is referential to the design of other optical imaging systems.