As the DOST-ASTI progresses in various fields of R&D, it goes without saying that the work we do in electronics R&D has hit quite the mark in 2019. Three of the agency’s produced papers that made a breakthrough in the IEEE TENCON 2018 has officially been published and awarded by the DOST National Academy of Science and Technology in 2019. 

Empirical Measurements of Antenna Polarization Mismatch and Misalignment Due to Angular Motion 

Link to Publication: https://ieeexplore.ieee.org/document/8650078

Written by Dr. Joel Joseph S. Marciano Jr., Senior Science Research Specialist Calvin Artemies Hilario, and Science Research Specialist II Mar Francis De Guzman, this paper was supported both by the DOST-ASTI and the Electronics Product Development Center (EPDC).

The paper aims to establish a more reliable wireless communications system in terms of making activities such as providing connectivity for small and largescale fishing vessels, localization and tracking of vessels, backhaul link for remote communities, gateway for weather sensors, emergency warning systems, and wireless network for other maritime activities – much more efficient and less costly. Therefore, it presented an approach in characterizing signal propagation in a maritime environment by replicating ocean wave-induced antenna motions in a semi-anechoic chamber.

Furthermore, various setup configurations were also applied as stated in the paper, by varying the tilting orientation, tilting period, and tilting range of the antenna in order to replicate various sea state conditions.

RF Power Amplifier Efficiency Improvement under Antenna Impedance Variation Using a Tunable Matching Network

Link to Publication: https://ieeexplore.ieee.org/document/8650383

Written by DOST ASTI Science Research Specialist II Mar Francis De Guzman, Genedyn Gems Mendoza, and Paul Timothy Quezon, this paper was supported by the DOST-ASTI and Analog Devices Philippines.

With the objective of analyzing and helping mitigate the effects of antenna input impedance to impedance performance, this paper used tunable matching network (TMN) that provides the direct compensation by re-matching the mismatched impedance. A power amplifier was designed first in order to observe the variation of its performance, and significant performance alterations were observed through various simulations that use ideal varactors in the TMN.

Compensation of Antenna Misalignment Using Selection Diversity for Maritime Communications

Link to Publication: https://ieeexplore.ieee.org/document/8650404

Written by DOST-ASTI Science Research Specialist II Mar Francis De Guzman, Greco Gervin Cruz, Leandrew Miguel Guzman, and Steven Matthew Cheng, this paper is supported by the Commission of Higher Education (CHED) Connecting Communities through Mobile Networks (CoCoMoNets) project of the Philippine-California Advanced Research Institutes (PCARI), DOST-ASTI, and the Electronic Products Development Center (EPDC).

The paper aims to reliable communication system for isolated coves through maritime communications that can be used across coastal and rural areas. In order to achieve this, the paper covered improvements of using diversity techniques for a 2.4 GHz communication link in the maritime environment were investigated. Spatial diversity, which uses independent multiple antennas to achieve a level of performance one antenna could not, was also employed. The presented plots exhibit a general trend showing that selection diversity reduces the received signal strength fluctuations to lower power, and minimizes the losses due to antenna misalignment.

For more information on these papers, visit https://asti.dost.gov.ph/projects/journals-and-scientific-papers/.