This paper at first illustrates implementation aspects and measurement results of a subcomponent for a multistandard RF identification (RFID) transponder. It is intended to be a common reference cell, both for basic UHF requirements and advanced application fields like local positioning and wireless sensing. Different single circuit topologies shown in previous studies or literature and their applicability for that RFID system are evaluated. After that, measurement results of two final circuit configurations, including a newly designed RC oscillator with metal-metal capacitors, are discussed and compared. Layout aspects for reducing the process variations and low power consumption are demonstrated. Simulation results show border conditions for the power supply of the transponder on chip level. Moreover, distance measurements with our first complete transponder compliant to the electronic product code protocol are shown. It includes the newly presented reference cells and other necessary transponder components. All chips are designed based on a 0.13-μm CMOS technology.

This paper presents an antenna for a Multistandard RFID transponder IC. The IC is capable of communicating at 13.56 and 868MHz. Additionally a FMCW functionality is implemented at 2.45GHz. Therefore the antenna has to provide multiband functionality for all frequency bands. The multiband functionality is achieved by designing two geometrically separated structures that resonate at different frequencies. The HF structure consists of two single layer inductances and a single layer capacitance. The UHF structure can be described as a modified dipole antenna. The maximum geometrical size of the transponder is restricted to the ID1 format. Consequently the available space for the antenna design is limited. Thus the antenna design is focused to the minimization of the HF and UHF structures assuring high performance in all frequency bands with regard to read rate and read range.