<p>Current printable memory technology are not suited for mass produc‐tion. With new inexpensive printed memory, it will be possible to manufacture cheap surveillance tags that are capable to tell the user if something has happened within a timeline. This project is within the ITC FrameProgram 7 founded project PriMeBits. The goal is to imple‐ment a write once read many memory (WORM) onto an RF‐tag together with a sensor that can sense wetness, which can be detected by EAS antitheft systems. Pre researches have been done in the fields printed capacitance, coils and WORMs, all printed with silver ink. Before implementation of a WORM onto a tag simulations and laboratory tests with adjustable resistances were made. Two different circuit models are simulated and tested. When connected to a tag and the WORM is un‐programmed, the EAS system should not trigger an alarm. But if the WORM is programmed by the sensor, the alarm should trigger. Results show that capacitances and WORMs are printable with this technique but coils are not due to high inner resistance. The simulations show that a tag built as an LCCR‐circuit is the best choice. This is also confirmed with tests done with real resistors. With WORMs connected to a tag the results show that approximately 70% of them work as intended, this is because the WORMs as of now are not completely developed. The conclusion of this project is that it is possible to implement a WORM onto a tag with further research, to make an inexpensive surveillance tag.</p> / PriMeBits

Current printable memory technology are not suited for mass produc‐tion. With new inexpensive printed memory, it will be possible to manufacture cheap surveillance tags that are capable to tell the user if something has happened within a timeline. This project is within the ITC FrameProgram 7 founded project PriMeBits. The goal is to imple‐ment a write once read many memory (WORM) onto an RF‐tag together with a sensor that can sense wetness, which can be detected by EAS antitheft systems. Pre researches have been done in the fields printed capacitance, coils and WORMs, all printed with silver ink. Before implementation of a WORM onto a tag simulations and laboratory tests with adjustable resistances were made. Two different circuit models are simulated and tested. When connected to a tag and the WORM is un‐programmed, the EAS system should not trigger an alarm. But if the WORM is programmed by the sensor, the alarm should trigger. Results show that capacitances and WORMs are printable with this technique but coils are not due to high inner resistance. The simulations show that a tag built as an LCCR‐circuit is the best choice. This is also confirmed with tests done with real resistors. With WORMs connected to a tag the results show that approximately 70% of them work as intended, this is because the WORMs as of now are not completely developed. The conclusion of this project is that it is possible to implement a WORM onto a tag with further research, to make an inexpensive surveillance tag. / PriMeBits

In recent years, passive radio frequency (RF) tags that communicate using modulated backscatter radiation have shown great potential for use in inventory management, parcel and postal tracking, for use as remote sensors, and in a host of other Radio Frequency Identification (RFID) applications. However, for the widespread use of these tags to become reality, much basic research is needed to reduce the cost, increase the range, and increase the reliability of the RF tag. This research seeks to enhance the performance of passive RF tags by developing a series of tests, or radio assay, to measure the following: the performance of RF tag antennas as a function of antenna material and manufacturing technique and the antenna performance when attached to various materials. The radio assay experiments are designed for RF tag antennas that operate in the far field of the tag reader and communicate using modulated backscatter radiation at 915 MHz. Three flexible, folded dipoles, printed on plastic substrates, were measured in the radio assay experiments. The results of the experiments include the following: the antenna gain penalty (relative to a baseline antenna) for each antenna material and manufacturing technique, the antenna gain penalty (relative to the free space antenna gain) due to material losses when the tag antenna is attached to an object, and the benefits (in terms of antenna gain) of tuning each tag antenna to the material to which it is attached. The results are presented in a form to aid RF engineers in the design of RF tag system link budgets.