Directivity enhancehment of antipodal vivaldi antenna using broadband metasurface lens

© 2019 IEEE.In this work, radiation performance of an antipodal Vivaldi antenna is enhanced using a broadband metasurface lens structure in 1-6 GHz bandwidth. Radiation pattern for the new antenna is more directive due to electromagnetic properties of the metasurface lens. In order to create such a lens, electrically responsive unit cells with high effective permittivity values are utilized. Unit cell dimensions are adjusted to display no resonant behaviour in the designated bandwidth. Overall lens structure is etched over the same substrate containing the antipodal Vivaldi antenna resulting in a compact and low profile design. Far-field radiation patterns indicate a more directive beam is radiated from the modified antenna with metasurface lens. Measurement and simulation results show that directivity is increased considerably without affecting the efficiency characteristics of the antenna due to the inclusion of the metasurface lens.


Inter-satellite optical communication networks: RF fading diversity for higher spectral efficiency
Şahin, Asaf Behzat; Kurnaz, S (2005-06-11)
Revolutionary developments in semiconductors lead to efficient deployment of lasers and photodetectors, thus enabling optical transmission of data signals, whether in fiber optic links or free space. Line of sight transmission characteristic of optics ensures the security of the data. With the incessant increase in the numbers of satellites and the data payload required to handle, it is inevitable that in the future we will see a shift towards optical networking, especially in the earth orbiting satellites....
Broadband absorption enhancement in an uncooled microbolometer infrared detector
Kebapci, Basak; Dervisoglu, Ozgecan; Battal, Enes; OKYAY, Ali Kemal; Akın, Tayfun (2014-05-08)
This paper introduces a method for a broadband absorption enhancement in the LWIR range (8-12 µm), in single layer microbolometer pixels with 35 μm pitch. For the first time in the literature, this study introduces a very simple and low cost approach to enhance the absorption by embedding plasmonic structures at the same level as the already existing metallic layer of a microbolometer pixel. The metal layer comprises the electrode and the arm structures on the body. Even though the periodicity of the plasmo...
Angular acceleration assisted stabilization of a-2 DOF gimbal platform
Öztürk, Taha; Leblebicioğlu, Mehmet Kemal; Department of Electrical and Electronics Engineering (2010)
In this thesis work construction of the angular acceleration signal of a 2-DOF gimbal platform and use of this signal for improving the stabilization performance is aimed. This topic can be divided into two subtopics, first being the construction of angular acceleration and the second being the use of this information in a way to improve system performance. Both problems should be tackled in order to get satisfactory results. The most important output of this work is defined as the demonstration of the impr...
Performance Analysis of Faster than Symbol Rate Sampling in 1-Bit Massive MIMO Systems
Üçüncü, Ali Bulut; Yılmaz, Ali Özgür (2017-05-25)
Low resolution analog-to-digital converters (ADC) attracted much attention lately for massive multiple-input multiple-output (MIMO) communication and systems with high bandwidth. Especially, 1-bit ADCs are suitable for such systems due to their low power consumption and cost. In this study, we illustrate the benefits of using faster than symbol rate (FTSR) sampling in an uplink massive MIMO system with 1-bit ADCs in terms of symbol error rate (SER). We show that FTSR sampling provides about 4 dB signal-to-n...
TCP-Peach++: Enhancement of TCP-Peach+ for satellite IP networks with asymmetrical bandwidth and persistent fades - (Invited paper)
Fang, J; Akan, OB (2005-01-01)
In this paper, an improvement to TCP-Peach+, called TCPPeach++, is proposed to improve the throughput performance for satellite IP networks with asymmetrical bandwidth and persistent fades. The delayed SACK scheme is adopted to address the problems due to bandwidth asymmetrical satellite links. A new protocol procedure, Hold State, is developed to address the link outages due to persistent fades. The simulation results show that TCP-Peach++ improves the throughput performance during rain fades and addresses...
Citation Formats
G. Sayan, “Directivity enhancehment of antipodal vivaldi antenna using broadband metasurface lens,” 2019, Accessed: 00, 2020. [Online]. Available: