System and method for implementing adaptive pulse position modulation (APPM) for improved optical communications performance
AssigneeLeidos, Inc.
InventorsSusan Harris, Mark Krepel, James Lundberg, Chris Fisher
Life of this patent
Estimating the term…
Abstract
The Adaptable Pulse Position Modulation (APPM) optical communication system and process facilitate wireless communications through turbid mediums including, but not limited to, smoke, airborne dust, mist, fog, clouds, water, seawater and water-to-air (air-to-water) interfaces by controlling the signal gain at the optical detector and controlling of the signal encoding to allow high data rate operation when the signal to noise ratio is high. The system also supports signal encoding redundancy to maintain good connectivity at the cost of the communication channel data rate as the signal to noise degrades.
Claims31
A communications system for facilitating communications across a wireless optical channel which includes an air-water interface comprising:
- an optical transmission device for transmitting encoded optical signals across the wireless optical channel, wherein the optical transmission device includes means for encoding the optical signals in accordance with at least one of multiple encoding schemes;
- an optical detection device for receiving transmitted optical signals from the optical transmission device across the wireless optical channel, wherein the optical detection device includes means for automatically adjusting gain of the optical detection device responsive to one or more measurements related to the received optical signals;
- wherein at least one of the optical transmission device and the optical detection device is located under water and another of the optical transmission device and the optical detection device is located in air;
- and
- further wherein the means for encoding the optical signals varies an applicable at least one of multiple encoding schemes during the communication with the optical detection device responsive to the one or more measurements related to the received optical signals.
A transceiver for facilitating wireless communications across an air-water interface comprising:
- an optical transmission device for transmitting optical signals, wherein the optical transmission device includes means for encoding data within the transmitted optical signals;
- an optical detection device for receiving optical signals, wherein the optical detection device includes means for automatically adjusting gain of the optical detection device responsive to one or more measurements related to the received optical signals;
- wherein at least one of the optical transmission device and the optical detection device is located under water and another of the optical transmission device and the optical detection device is located in air;
- and
- a digital signal processor (DSP) for controlling the means for encoding data and the means for automatically adjusting gain of the optical detection device.
A communications system for facilitating communications across a wireless optical channel which includes an air-water interface comprising:
- a first transceiver including a first optical transmission device for transmitting optical signals and a first optical detection device for receiving optical signals;
- a second transceiver including a second optical transmission device for transmitting optical signals and a second optical detection device for receiving optical signals;
- wherein the first transceiver and the second transceiver include means for adapting one or more components thereof during the communications across the optical channel responsive to changes in the received optical signals;
- and
- further wherein at least one of the first and second transceivers is located underwater and another of the another of the first and second transceivers is located in air.
Dependencies are inferred from the claim text.