公开(公告)号：US20250125874A1

公开(公告)日：2025-04-17

申请号：US18490381

申请日：2023-10-19

Applicant: KING FAHD UNIVERSITY OF PETROLEUM AND MINERALS

Inventor： Khurram Karim QURESHI ,  Jawad MIRZA ,  Ahmad ATIEH ,  Salman Abdul GHAFOOR ,  Sheikh Sharif IQBAL

IPC: H04B10/118 ,  H01S3/067 ,  H01S3/094 ,  H04B10/564

Abstract: A dual-hop system for optical wireless communication between a base station on Earth and satellite is described. The system includes a first Thulium-Doped Fiber Amplifier (TDFA) at the base station and a second TDFS installed in a High-Altitude Platform Station (HAPS). The first TDF A includes a first thulium-doped fiber (TDF) and a first set of optical pumps. The first TDFA amplifies an input optical signal for wireless transmission to the HAPS installed at a specific altitude. The amplified signal is received by the second TDFA at HAPS. The second TDFA includes a second TDF and a second set of optical pumps. The signal amplified by the second TDFA is compensated for attenuation before it is wirelessly transmitted to the satellite. Both TDFAs ensure that the amplification of the optical signals, either through power amplification or gain, meets specified criteria to maintain the integrity and quality of the transmitted signals.

公开(公告)号：US20250102730A1

公开(公告)日：2025-03-27

申请号：US18473689

申请日：2023-09-25

Applicant: KING FAHD UNIVERSITY OF PETROLEUM AND MINERALS

Inventor： Khurram Karim QURESHI ,  Eid M. AL-MUTAIRI ,  Sheikh Sharif IQBAL ,  Md. Ahasan HABIB

IPC: G02B6/02 ,  G01N21/45

Abstract: A hollow-core photonic crystal fiber for sensing an oil includes a hexagonal core wall, a cladding region, and a circular layer. The hexagonal core wall defines a hollow space, where a core diameter is equal to a distance between two opposing inner vertices of the hexagonal core wall. The cladding region includes a circular cladding segment and up to four cladding arms, where the up to four cladding arms extend from the circular cladding segment to four outer vertices of the hexagonal core wall. An inner wall of the circular cladding segment, the up to four cladding arms and an outer surface of the hexagonal core wall define up to four wedge shaped air gaps. The cladding region has an inner radius with a range from 2.0 up to 2.4 times the core diameter and an outer radius with a range from 2.1 up to 2.6 times the core diameter.