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- Wu, Kuan-Hsun, et al.
(författare)
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Considerations of SiP based Antenna in Package/Module (AiP/AiM) Design at Sub-Terahertz Frequencies for Potential B5G/6G Applications
- 2021
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Ingår i: Proceedings - Electronic Components and Technology Conference. - 0569-5503. ; 2021-June, s. 1162-1168
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Konferensbidrag (refereegranskat)abstract
- Antenna-in-Package/Module (AiP/AiM) are the primary technologies to realize the RF subsystems for frequencies beyond millimeter-wave (mmW) bands, including sub-terahertz for potential B5G/6G applications. Due to the small wavelength, the mechanical process of the current system-in-package (SiP) results in limitations to realize antenna arrays at sub-terahertz. In this paper, the mechanical limits to cause radiation discrepancy is investigated by designing an AiP/AiM at 110 GHz band. Through the parametric studies based on the currently available cheap SiP process, one may summarize the considerations of AiP/AiM design for beyond sub-terahertz frequencies. The examination will consider the design of an 8x8 antenna array to provide a radiation gain of 20 dBi. Numerical full-wave simulations by HFSS were performed to obtain reliable behaviors of AiP/AiM radiations.
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3. |
- Lu, R.S., et al.
(författare)
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A ring-like accretion structure in M87 connecting its black hole and jet
- 2023
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Ingår i: Nature. - 0028-0836 .- 1476-4687. ; 616:7958, s. 686-690
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Tidskriftsartikel (refereegranskat)abstract
- The nearby radio galaxy M87 is a prime target for studying black hole accretion and jet formation1,2. Event Horizon Telescope observations of M87 in 2017, at a wavelength of 1.3 mm, revealed a ring-like structure, which was interpreted as gravitationally lensed emission around a central black hole3. Here we report images of M87 obtained in 2018, at a wavelength of 3.5 mm, showing that the compact radio core is spatially resolved. High-resolution imaging shows a ring-like structure of [Formula: see text] Schwarzschild radii in diameter, approximately 50% larger than that seen at 1.3 mm. The outer edge at 3.5 mm is also larger than that at 1.3 mm. This larger and thicker ring indicates a substantial contribution from the accretion flow with absorption effects, in addition to the gravitationally lensed ring-like emission. The images show that the edge-brightened jet connects to the accretion flow of the black hole. Close to the black hole, the emission profile of the jet-launching region is wider than the expected profile of a black-hole-driven jet, suggesting the possible presence of a wind associated with the accretion flow.
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