Design of an RF Transmitter for RFID Tags in a New Technology with Ultra Thin Silicon Substrates

The development of the Gateforest technology with new ultra-thin silicon substrates triggered research into its possible applications. RFID implementation, specifically the transmitter implementation, on this technology is investigated in this document. To start with, the measurement and simulation of circuit elements (passive and active) at high frequencies is done in order to verify that the chip could operate at radio frequencies. The document then discusses the basic structures that are involved in the design of the transmitter test-structures, followed by the theory of operation of voltage controlled oscillators. The implementation of the circuits is done to explore the possibility of creating an RFID tag using a new technology. For this, 4 transmitter circuits are designed, two ring oscillators and two cross-coupled oscillators, such that they cover 3 different operating frequencies (433 MHz ISM band, 869 MHz SRD band and 2.45 GHz ISM band). They are also designed in both differential and single-ended form to cover a good set of different parameters for testing. In circuit design, high complexity of the structures is avoided because this is only a first prototype and special care was taken in order to provide a wide tuning range (≥ 40%). This is important in order to assure that the operating frequency could be reachable despite temperature and process variations. The circuit layout is done such that it fitted on one chip provided by IMS-CHIPS. The pad connections are done so that testing of the chip is facilitated as much as possible.