Patents by Inventor David J Geisler

David J Geisler has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Multi-spatial mode enabled PAT and AO terminal architecture for free-space optical communications
    Patent number: 10892824
    Abstract: Many free-space optical (FSO) communications systems use pointing, acquisition, and tracking (PAT) systems to align the transmit and receive apertures for efficiently coupling received light to a detector. Conventional PAT systems divert energy from the communications receiver to a photodiode array for measuring tilt in the focal plane. Unfortunately, diverting energy from communications to PAT reduces SNR and sensitivity for communications. The PAT terminal disclosed here determines tilt angle without diverting energy from the communications receiver. It tracks the power in different spatial modes and uses that power distribution to determine tilt information for PAT. It does this with a passive mode converter, such as a photonic lantern, that maps power in each spatial mode at the receive aperture to a different single-mode output.
    Type: Grant
    Filed: February 28, 2020
    Date of Patent: January 12, 2021
    Assignee: Massachusetts Institute of Technology
    Inventors: David J Geisler, Timothy M Yarnall
  • Multi-Spatial Mode Enabled PAT and AO Terminal Architecture for Free-Space Optical Communications
    Publication number: 20200343973
    Abstract: Many free-space optical (FSO) communications systems use pointing, acquisition, and tracking (PAT) systems to align the transmit and receive apertures for efficiently coupling received light to a detector. Conventional PAT systems divert energy from the communications receiver to a photodiode array for measuring tilt in the focal plane. Unfortunately, diverting energy from communications to PAT reduces SNR and sensitivity for communications. The PAT terminal disclosed here determines tilt angle without diverting energy from the communications receiver. It tracks the power in different spatial modes and uses that power distribution to determine tilt information for PAT. It does this with a passive mode converter, such as a photonic lantern, that maps power in each spatial mode at the receive aperture to a different single-mode output.
    Type: Application
    Filed: February 28, 2020
    Publication date: October 29, 2020
    Applicant: Massachusetts Institute of Technology
    Inventors: David J Geisler, Timothy M Yarnall