Design and Development of Multifunctional UWB Antennas for Cognitive Radio Applications
Avionics
The introduction of new wireless services and the quest for high-speed communication with enhanced data rate and channel capacity have led to unprecedented congestion in the RF spectrum. A cognitive radio (CR) system provides a sustainable solution due to its opportunistic and intelligent usage of the spectrum using ‘dynamic’ spectrum policy. In a CR system, the spectrum is shared using the sub-bands in an ultrawideband (UWB) frequency range. The available spectrum over an UWB spectrum which includes/excludes the frequency band of the primary users, known as ‘white space’, is scanned to detect the unused/idle band which is then dynamically allotted to the secondary users for ‘communication’. This dynamic allocation of sub-bands through frequency scanning and subsequent communication, requires an intelligent multifunctional antenna system. More specifically, an UWB antenna (known as sensing antenna) is used to detect the ‘white space’ and a narrow-band antenna is required for ‘communication’.
Caption: Conceptual block diagram and various types of CR Antennas
Dr. Saha’s research group in the department of Avionics has contributed in design and development of new types and class of antennas for CR applications [1]-[3]. The group has shown that by improvised designing of the UWB antennas and loading of various switching and tuning elements, such as, PIN diodes, varactor diodes etc. multfuncional antennas with dual tunable features can be realized. The concept has been established with precise computation of the resontaors & radiators and have been established for various genres of UWB radiator, such as circular monopole antenna, its variants and tapered slot antennas.
Ref: C. Saha, J. Y. Siddiqui and Y.M.M. Antar, “Mulltifunctional Ultrawideband Antennas: Trends, Techniques and Applications”, Taylor and Francis, 6000 Broken Sound Parkway , NW, Suite 300, Boca Raton, Florida 33487, USA (April 2019, ISBN: 9781138553545).
Ref: S. Keerthipriya, C.Saha, D. Sarkar, JY Siddiqui, and Y.M.M. Antar, “ Varactor Controlled SRR Integrated Frequency Reconfigurable Multifunctional Antenna”, IEEE Antennas and Propagation Magazine, July 2021 ( Early Access). doi: 10.1109/MAP.2021.3106893.
Ref: L.Ahmed, C. Saha, Y.M.M. Antar, and J.Y. Siddiqui, “ An antenna advance for Cognitive Radio: Introducing Multilayered Split Ring Resonator Loaded Printed Ultra-Wideband Antenna with Multi-Functional Characteristics” IEEE Antennas and Propagation Magazine, Vol. 60, issue. 2, pp 20-33, March 2018.
