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Optical Couplers
Published in Erich Kasper, Jinzhong Yu, Silicon-Based Photonics, 2020
This kind of inverted tapered spot-size converter had a well-considered structure. However, its insertion loss was still higher than 3 dB. Furthermore, it was very sensitive to the polarization state. Simulation showed that the insertion losses for TM-like and TE-like modes at 1550 nm were 3.3 dB and 6 dB, respectively. The total measured insertion loss was 9.2 dB, including about 5 dB loss caused by the nano-optical waveguides, and this was quite close to the simulated result. The insertion loss originated from the mode mismatch loss between the optical fiber and tip facet modes and from mode conversion of the low-confined mode at the tip facet into the high-confined mode in the waveguide. Meanwhile, its misalignment tolerance was relatively large and the additional insertion loss for 1.2 μm misalignment in both horizontal and vertical directions was only 1 dB. This mainly resulted from the large field dimensions at the tip.
Active and Diversity Receiving Antenna Systems
Published in Victor Rabinovich, Nikolai Alexandrov, Basim Alkhateeb, Automotive Antenna Design and Applications, 2010
Victor Rabinovich, Nikolai Alexandrov, Basim Alkhateeb
The mismatch loss at the input determines the magnitude of the input reflection coefficient. For example, if we have to sacrifice a 1 dB gain at the input port for the best noise value, the 1 dB mismatch loss converts to a 0.45 input reflection coefficient magnitude. A 2 dB mismatch loss leads to an input reflection coefficient magnitude of 0.6—a poor input match.
Emperor Penguin Optimization Based MPPT for PV System under Different Irradiation Condition
Published in Electric Power Components and Systems, 2023
Muhilan Paramasivam, Senthilkumar Subramaniam
Due to the scarcity of the resources like fossil fuels, renewable energy resources (RER) are emerging in the world to meet the requirement for electricity. The photovoltaic (PV) is a widely used power generator because of its unlimited energy resources [1]. The power generated by PV is limited by hotspots, partial shading and cracks [2, 3]. Because of the intermittent characteristics of its resources, it is widely used by researchers as distributed generator [4]. In a distributed system, the PV system will produce low emissions, reduced power loss and higher power quality [5]. Due to the high penetration of the radiation and temperature into the PV cell, the operating condition of the cell will obtain transformation [6]. When a considerable number of PV modules are used for the installation, the design or arrangement of the PV module is necessary due to power loss. The arrangement of the PV module can be a simple series connection, simple parallel [7, 8] connection, serial-parallel (SP) configuration [9], honey-comb (HC) configuration [10], total cross tied (TCT) configuration [11] and bridge-linked (BL) [12] configuration. In series string connected configuration, the mismatch loss has a huge impact. The HC, TCT, and BL configured networks reduce the mismatch loss. The employment of those configured networks brings better out-turn from the PV system.