Reconfigurable Antenna Systems · 2019-09-05 · antenna to adapt to a pre-determined operative...
Transcript of Reconfigurable Antenna Systems · 2019-09-05 · antenna to adapt to a pre-determined operative...
Reconfigurable Antenna Systems Enrico Tolin
Supervisor: Prof.ssa Francesca Vipiana
Submitted and published works • E. Tolin, A. Bahr, M. Geissler and F. Vipiana, "Flexible and cost effective reconfigurable UHF RFID antenna system," 11th
European Conference on Antennas and Propagation (EUCAP), Paris 2017.
• E. Tolin, O. Litschke, S. Bruni and F. Vipiana, "Innovative Rotman lens setup for extended scan range array antennas," IEEE-
APS Topical Conference on Antennas and Propagation in Wireless Communications (IEEE APWC), Verona 2017.
• E. Tolin, O. Litschke and F. Vipiana, " Phase shifters design for Rotman lens based beamforming network scan range
extension ", 2018 IEEE International Symposium on Antennas and Propagation and USNC-URSI Radio Science Meeting,
Boston 2018.
• E. Tolin, O. Litschke, S. Bruni and F. Vipiana, "Flexible and cost effective reconfigurable UHF RFID antenna system," 11th
European Conference on Antennas and Propagation (EUCAP), London 2018.
• E. Tolin, O. Litschke, S. Bruni and F. Vipiana, “Extended scan range radar system based on Rotman lens,“ in preparation
List of attended classes • 01MMRRV – Tecniche numeriche avanzate per l'analisi ed il progetto di antenne (26/5/2017, 4 credits)
• 01QFFRV – Tecniche innovative per l'ottimizzazione (11/9/2017, 4 credits)
• 01QFDRV – Photonics: a key enabling technology for engineering applications (11/9/2017, 5 credits)
• 01RZTRV – Il criterio di responsabilità nella ricerca e nell'innovazione - l'impatto sulle sfide sociali
(24/5/2017, 4 credits)
• 01RZURV – Il criterio di responsabilità nella ricerca e nell'innovazione - Il ruolo dell'ICT nell'era di internet
(30/5/2017, 4 credits)
• 01QTXRV – BIO/CMOS interfaces and co-design (18/10/2017, 3 credits )
• 01QRNRV – Electromagnetic dosimetry in MRI: computational and experimental methods (9/11/2017, 4
credits)
• ESoA Course – RADAR 2020, FUTURE RADAR SYSTEMS (7/5/2018, 3 ECTS credits)
• The frequency and polarization agile RFID antenna presents a new method to apply the
reconfigurability concept to an antenna: in fact the tuning element is not inserted directly in
the antenna but instead it is used in the matching network. For changing the polarization
(V, H and ±45°), 3 different concepts of reconfigurable feeding network has been
designed, employing switchable delay and metamaterials lines. A very compact solution
using reconfigurable rat-race coupler has been developed.
• The extended scan range applied to the Rotman Lens as beamformer allow to double the
scan range of the Rotman Lens. For the investigated case of a ±30° Rotman Lens design
a dedicated phase management unit has been designed. A highly integrated solution
employing a novel switchable microstrip-to-slot coupled phase inverter (using 4 PIN diodes
for selecting the desired Electric field orientation).
Novel contributions
Addressed research questions/problems
• Polarization agility is also added, allowing the patch to radiate in horizontal, vertical and
the combination of these two polarization (i.e. +45° and -45°). This approach ensures
better performance in terms of Polarization Loss Factor (PLF) compared to standard
circular polarization approach.
• Rotman lenses are key devices in many phased array applications because of good
performance and relatively simple development and low cost fabrication. Anyway, its use in
applications like automotive radars is limited by the drawback of having poor
performance level at wide scan angles, which leads to a bulky and sub-optimal designs.
Therefore, an innovative phase management has been developed for doubling the scan
range of an antenna array fed by a Rotman lens. It combines two effects called Complete
Beam Shifting and Beam Mirroring.
• The phase management unit employ a progressive phase shift for moving all the beams
toward positive/negative scan angles (90° for the examined case), while the Beam
Mirroring introduces a shift on the opposite side of the scan range (in the basic unit cell
only 2 phase inversion are needed in the case of Rotman lens designed for ±30° scan).
By combining these 2 effects a doubling scan range can be obtained (approximately 60°).
Research context and motivation • Traditionally wireless systems are designed for single predefined operations. To overcome
from limitations due to the standard approach reconfigurable antennas and systems are
employed for increase performance and to change the intrinsic characteristic of the
antenna to adapt to a pre-determined operative state (frequency, pattern, polarization).
Adopted methodologies • Due to the heterogeneous nature of this topic, different methodologies were exploited for
designing the reconfigurable antenna systems. Moreover, an important part of the research
concerned the investigation of new technology for applying this techniques in an industrial
Future work • Final measurements on the RFID antenna, showing effective frequency reconfigurability
and selectable polarization.
• Application to the extending scan range method to a 77GHz array with the use of new
technologies like tunable materials, preferably using waveguide technology for minimizing
losses.
PhD program in
Electrical, Electronics and
Communications Engineering
XXXII Cycle
Rotman Lens
Antenna array
Phase Management
Array side
outputs φD
φB
φC
φD
φA 90° 180° 270° 360°
-90° 180° -270° 360°
0° 30° -30 60° 0° 30° -30°
Complete Beam
Shifting
Mirror
Beam Mirroring 60° 0° 30° -30° -60°
Fixed phase shifting superimposed to Rotman
Lens
Phase inversion applied at every second antenna
array input
Beam Shift
Special case of Rotman
Lens with max scan range
angle of ±30° allows a
compact and efficient
phase management unit
• A frequency reconfigurable RFID reader´s
antenna aim to unify the radiating element
that has to be used in Europe and USA area
has been designed. In particular the
reconfigurability concept is applied to the
matching network, by using a high power
CMOS switch, and taking advantage of wide
band radiation capability of patch antennas.
environment. In particular the combination of
circuit simulation and EM modeling was the key
element for the creation and verification of the
proposed solutions.
• The interaction between active components and
EM structures leads to an accurate modelling of
the switches and co-simulation of the complete
system with a full wave simulator.
Frequency Agility Polarization Agility
PIN Diodes
Pol V
Pol H
Input
Polarization control
Frequency control
-60° -30° 30° 60°
Extended Scan Range
• Reconfigurable antennas are important in industrial
application because they allow to achieve a better
integration, less costs and maximize connectivity.
• Automotive Radar technology is growing exponentially
in recent years, with great efforts for the development of
the Advanced Driver Assistant System (ADAS), following
the goal of fully automated driving by the year 2025.