Daniele Inserra

Planar antenna array design considerations for RFID electronic toll collection system

This paper deals with the design of a radio-frequency identification (RFID) reader for electronic toll collection (ETC) systems. The ETC scheme herein considered comprises a planar antenna array as radiating element of the RFID reader. This reader is required to be capable of alternatively illuminating three (or more) road surface portions called coverage areas, where a transponder (tag) might be present. Coverage areas have to be well-defined in order to avoid collision. This paper treats with the design of the RFID reader, with special emphasis on the coverage area synthesis in the practical case of a limited size antenna array.

Linear optimization of antenna array for radiation pattern defined on a planar surface

ABSTRACT In this contribution, the antenna array synthesis for radiation pattern defined on a planar surface is described. This can be required when the electric field r-decay factor effect cannot be neglected, e.g. an antenna array mechanically tilted and a specific pattern defined in terms of cartesian coordinates. Differently from the classical sidelobe level reduction optimization problem, the case in which both a constant power bounded area and a sidelobe suppression region are defined and required to be synthesized is herein addressed. The general nonlinear optimization problem is first presented; then, the derivation of some sub-optimal linear problems based on practical implementation hypothesis is described, with the advantage of a reduced computational complexity. Numerical results validate the effectiveness of the proposed method.

High gain linearly polarized wideband UHF antenna based on substrate integrated coaxial line feeding network

A high gain antenna array for the ultra high frequency (UHF) radio frequency identification (RFID) universal bandwidth (840–960 MHz) is herein proposed. A corporate feeding network is designed with substrate integrated coaxial line (SICL) technology in order to minimize losses due to dispersive mode propagation. Suspended E-shaped patches are employed to broaden the frequency band and improve antenna gain. A 2 ×2 antenna array prototype is manufactured and measured, revealing a sufficient S11 < −10dB bandwidth to cover the universal UHF RFID band, and a gain larger than 11 dBi within the bandwidth of interest.

Design of a Microstrip Series Power Divider for Sequentially Rotated Nonuniform Antenna Array

This paper deals with the design of a microstrip series power divider for circularly polarized sequential rotational antenna array. The theoretical description of the design is firstly proposed, comprising the cases of nonuniform weighted antenna arrays. A more flexible open octagon shape instead of the classical open ring is suggested, highlighting benefits in the case of nonuniform power distribution. A design example of an ultra-high frequency (UHF) band sequentially rotated Tschebischeff antenna array finally demonstrates the effectiveness of the proposed implementation.

Communication area synthesis for next generation highway ETC systems

In this paper, some requirements of next generation highway electronic toll collection (ETC) systems are presented. In particular, the trend of moving toward a completely open road free-flow tolling concept that, ideally, comprises the possibility of having vehicles with speed up to 200 km/h, encourages the elongation of the communication area or, however, a more efficient synthesis of the antenna radiation pattern. For this reason, the concept of communication area in the context of highway radio-frequency identification (RFID) based ETC is first investigated, and then a simple methodology with antenna array to synthesize a specific communication area by exploiting well known synthesis techniques, e.g. Tschebyscheff distribution, is proposed.