Isaac Balbin

Multiresonator-Based Chipless RFID System for Low-Cost Item Tracking

A fully passive printable chipless RFID system is presented. The chipless tag uses the amplitude and phase of the spectral signature of a multiresonator circuit and provides 1:1 correspondence of data bits. The tag comprises of a microstrip spiral multiresonator and cross-polarized transmitting and receiving microstrip ultra-wideband disc loaded monopole antennas. The reader antenna is a log periodic dipole antenna with average 5.5-dBi gain. Firstly, a 6-bit chipless tag is designed to encode 000000 and 010101 IDs. Finally, a 35-bit chipless tag based on the same principle is presented. The tag has potentials for low-cost item tagging such as banknotes and secured documents.

Phase-Encoded Chipless RFID Transponder for Large-Scale Low-Cost Applications

A novel 3 b chipless RFID transponder is presented. The transponder comprises three microstrip patch antennas, which are loaded with open circuited (O/C) high impedance stubs. The antennas are resonant at nearby frequencies, and when excited with their respective resonant frequency signals, they re-radiate backscattered signals with distinct phase characteristics. This phase information is encoded as hexadecimal bits for the proposed chipless RFID tag. Both the CST Microwave Studio full-wave solver and the anechoic chamber measurements show a 30deg phase step for the 3 b chipless RFID transponder. It it easily transferred to printed technology, and it may find applications in the mass identification market.

Quasi-static modeling of defected ground structure

A quasi-static equivalent-circuit model of a dumbbell-shaped defected ground structure is developed. The equivalent-circuit model is derived from the equivalent inductance and capacitance developed due to the perturbed return current path on the ground and the narrow gap, respectively. The theory is validated against the commercial full-wave solver CST Microwave Studio. Finally, the calculated results are compared with the measured results. Good agreement between the theory, the commercially available numerical analyses, and the experimental results validates the developed theoretical model.

A Novel Chipless RFID System Based on Planar Multiresonators for Barcode Replacement

RFID is taking the world by storm but lowering the price of the tag is a necessity in order to completely replace barcode systems with RFID systems. Researchers around the world have been working on chipless RFID systems. In this paper we present a novel chipless RFID system for barcode replacement. The system can be effectively used in conveyor belt applications. It uses spectral signatures to encoded data and hence provide a unique ID for every tagged object. The chipless tag is fully passive and planar.

Chipless Frequency Signature Based RFID Transponders

RFID technology is taking the world by storm and there is a requirement for having cheap RFID tags. Chipless transponders offer cheap solutions which can compare with the barcode. We present two types of frequency signature based RFID transponders using multiresonators and fractal antennas. In this article we present the novel chipless RFID concept and simulated and measured results of the chipless tags.

The development and design of a novel chipless RFID system for low-cost item tracking

In this paper, the novel chipless RFID system uses multiresonators to encode the spectral signature into multi-bit identification data for items. We have shown simulation and experimental results which confirm that by interrogating the transponder with a multi-frequency signal, it is possible to detect the distinct magnitude and phase variations of the received tag signal and thus decode the transponders ID. The frequency signature based system is the first of its kind to use the amplitude as well as phase to encode data which increases the reading range from a few millimeters to more than 20 cm. The chipless tag has a great market potential if printed on plastic substrate using transparent conductive (silver) ink for low-cost item tracking.

Development of a low-cost semi-passive transponder for sensor applications at 2.4GHz

Development of a simple low-cost radio frequency identification (RFID) transponder for wireless sensor networks at 2.4 GHz is presented. The transponder is comprised of a rectangular patch antenna, RF modulating circuit and a low power mixed signal microcontroller from Texas Instruments. The transponder is powered by a 3 V pill-box battery and uses amplitude shift keying (ASK) backscatter modulation to communicate with a RFID reader. In this paper we present the design steps and measured results of the developed semi-passive RFID transponder.

Novel N - way Power Divider and Array Configuration for RFID Readers operating at 5.8 GHz

A novel N - way power divider has been designed to be used in arrays for the development of readers in RFID systems. In contrast with the conventional power dividers, this power divider can accommodate any number of power division starting from 1 to 16 and higher from one central circular microstrip patch acting like a hub. Like other conventional power dividers, this power divider can also be put in cascade. The power divider is broadband in nature and greatly reduces space used by arrays compared to the conventional designs. Additionally, the scope of this power divider to be used in RFID systems is huge opening an entire new approach to tracking electronics.

Quasi-Static Analysis of Defected Ground Structure

A quasi-static equivalent circuit model of a dumbbell shaped defected ground structure (DGS) is developed. The equivalent circuit model is derived from the equivalent inductance and capacitance developed due to the perturbed returned current path on the ground and the narrow gap, respectively. The theory is validated against the commercial full-wave solver CST Microwave Studio. Finally, the calculated results are compared with the measured results. Good agreement between the theory, the commercially available numerical analyses and the experimental results validates the developed theoretical model.