Paolo Maxia

DESIGN OF A PRINTED LOG-PERIODIC DIPOLE ARRAY FOR ULTRA-WIDEBAND APPLICATIONS

A printed Log-periodic dipole array (LPDA) is presented, operating over the C, X and Ku bands. The antenna feeding structure consists of two coaxial cables, in order to realize an inflnite balun which provides the required broadband input matching. The second coaxial cable mirrors the flrst one, connected to the antenna input, and is capable of both stabilizing the antenna phase center and improving the radiation pattern. The antenna has been designed using CST Microwave Studio, with an useful frequency range of 4{18GHz. Moreover, both simulated and measured results show that the proposed LPDA can be successfully used as an Ultra Wideband Antenna in the range 4.25{13.25GHz, in which its phase center remains stable.

A Printed LPDA Fed by a Coplanar Waveguide for Broadband Applications

A printed log-periodic dipole array (LPDA), operating between 3 and 6 GHz and fed with a coplanar waveguide, is presented. The antenna has been designed starting from Carrels theory, optimized using CST Microwave Studio 2012, and then realized. The comparison between simulated and measured results shows that the proposed antenna can be used for broadband applications in the whole operating frequency band (3-6 GHz), with a very good input matching and a satisfactory endfire radiation pattern.

Evaluation of a microwave resonant cavity as a reactor for enzyme reactions

We present here the design and analysis of a microwave resonant cavity to evaluate the effect of RF electromagnetic field on enzyme reactions. The cavity has been first designed using CST Microwave Studio. Then, its behaviour in the actual use has been evaluated using the COMSOL multiphysics. The presented results show that such cavity can be quite effective.

A narrowband chipless multiresonator tag for UHF RFID

In this work, a narrowband fully passive printable RFID chipless tag, working in the UHF band, is presented. The tag consists of two cross-polarized transmitting and receiving microstrip broadband circular monopole antennas, loaded with multiple cascaded resonators, each one unambiguously corresponding to one data bit. The proposed antenna has a compact size, a low cost of fabrication, and a very compact frequency bandwidth. It uses spectral signatures to encode data, and hence provides a unique ID for every tagged object. The antenna has been designed using a general purpose 3D CAD, CST Microwave Studio, and measured results are in very good agreement with the simulations. The designed RFID tag has been tested in anechoic chamber, and the unique spectral signature of the tag has been correctly detected. The proposed tag design is suitable for mass deployment for low cost items.

A Multiband Printed Log-Periodic Dipole Array for Wireless Communications

A multiband printed Log-periodic dipole array (LPDA) antenna for wireless communications is presented. The antenna has been designed starting from Carrel’s theory, optimized using CST Microwave Studio 2012, and then realized. The comparison between simulated and measured results shows that the proposed antenna can be used for wireless communications both in the S (2.4–3 GHz) and in the C (5.2–5.8 GHz) frequency bands, with very good input matching and a satisfactory end-fire radiation pattern. Moreover, it has a compact size, is very easy to realize, and presents an excellent out-of-band rejection, without the use of stop-band filters, thus avoiding interference out of its operating frequency band.

A Multiband Proximity-Coupled-Fed Flexible Microstrip Antenna for Wireless Systems

A multiband printed microstrip antenna for wireless communications is presented. The antenna is fed by a proximity-coupled microstrip line, and it is printed on a flexible substrate. The antenna has been designed using a general-purpose 3D computer-aided design software (CAD), CST Microwave Studio, and then realized. The comparison between simulated and measured results shows that the proposed antenna can be used for wireless communications for WLAN systems, covering both the WLAN S-band (2.45 GHz) and C-band (5.2 GHz), and the Wi-Max 3.5 GHz band, with satisfactory input matching and broadside radiation pattern. Moreover, it has a compact size, is very easy to realize, and presents a discrete out-of-band rejection, without requiring the use of stop-band filters. The proposed structure can be used also as a conformal antenna, and its frequency response and radiated field are satisfactory for curvatures up to 65°.

A CPW-fed printed LPDA for wireless communications

A dual-band printed Log-periodic dipole array (LPDA) antenna for wireless communications is presented. The LPDA has been designed on a PET substrate and implemented by inkjet printing using a conductive ink, in order to obtain a low-cost antenna, and is fully planar, since it is fed by a coplanar waveguide. The proposed antenna can be used for wireless communications both in the S (2.4-2.484 GHz) and C (5.2-5.8 GHz) frequency bands, and a good out-of-band rejection has been obtained without using stop-band filters. The LPDA has been designed using a general purpose 3D CAD, CST Microwave Studio, and fully characterized, with measured results very close to the simulations.

A wire antenna for broadband WLAN applications

This paper presents a wire antenna for multi-band WLAN application, designed using the Structure-Based Evolutionary Programming, and having a very simple geometry. The antenna has been analysed with NEC-2 during the evolutionary process, and the outcome of the procedure shows a very good performance, with a -10dB bandwidth that covers the required frequencies for multi-band WLAN applications (2.4/5.2/5.8 GHz) and beyond, and an end-fire gain greater than 11 dB.

A multi-band antenna for WLAN applications

This paper presents a small truncated waveguide fed by a microstrip line through a transverse coupling slot for multi-band WLAN applications. The proposed radiating element allows to obtain a high radiated power, with a very low cross-polar component in the radiated field, with a -10 dB bandwidth that covers the required frequencies for multi-band WLAN applications (5.2/5.4/5.8 GHz).

A wire antenna for broadband WLAN and Wi-Fi applications

This paper presents a wire antenna for multi-band WLAN application, designed using the Structure-Based Evolutionary Programming, and having a very simple geometry. The antenna has been analysed with NEC-2 during the evolutionary process, and the outcome of the procedure shows a very good performance, with a -10dB bandwidth that covers the required frequencies for multi-band WLAN applications (2.4/5.2/5.8 GHz) and beyond, and an end-fire gain greater than 11 dB.