# US 12,015,694 B2 · Optical channel intensity streaming encryption > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,015,694 B2 - Document ID: US12015694B2 - Status: Granted - Kind: B2 - Application number: 17/487,924 - Filed: 2021-09-28 - Published: 2022-03-31 - Granted: 2024-06-18 - Earliest claimed: 2020-09-28 - Assignees: California Institute of Technology - Applicants: California Institute of Technology - Inventors: Jian Xu; Changhuei Yang - Web page: https://patentgrep.com/patent/US12015694B2 ## CPC - H04L 9/0656: {Pseudorandom key sequence combined element-for-element with data sequence, e.g. one-time-pad [OTP] or Vernam's cipher} - G02B 27/48: Laser speckle optics - G09C 1/00: Apparatus or methods whereby a given sequence of signs, e.g. an intelligible text, is transformed into an unintelligible sequence of signs by transposing the signs or groups of signs or by replacing them by others according to a predetermined system (cryptographic typewriters G09C3/00) - H04B 10/2537: due to scattering processes, e.g. Raman or Brillouin scattering - H04B 10/54: Intensity modulation - H04B 10/66: Non-coherent receivers, e.g. using direct detection - H04B 10/70: Photonic quantum communication - H04L 9/0875: {based on channel impulse response [CIR]} - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS - G09C: CIPHERING OR DECIPHERING APPARATUS FOR CRYPTOGRAPHIC OR OTHER PURPOSES INVOLVING THE NEED FOR SECRECY - H04B: TRANSMISSION ## Abstract A communication system including a first detector; a first scattering medium; a second detector; an intensity modulator; a second scattering medium; wherein electromagnetic radiation transmitted from a first spot at the first scattering medium, and scattered by and through the first scattering medium and then the second scattering medium, forms a first speckle pattern detected by the second detector. The intensity modulator outputs a second spot of electromagnetic radiation representing the “ones” in a data stream at locations of the bright speckles (or at locations of the dark speckles to represent the “zeros” in the data stream) so that the electromagnetic radiation, transmitted from the second spot and scattered by and through the second scattering medium and then the first scattering medium, forms one or more second bright or dark speckles on the first detector. The data stream can be constructed from the second bright or dark speckles. ## Claims ### Claim 1 A communication system, comprising: a first source of electromagnetic radiation comprising a point source transmitter device; a first detector; a first scattering medium electromagnetically coupled to the first source and the first detector; a second detector; an intensity modulator; a second scattering medium electromagnetically coupled to the second detector and the intensity modulator; wherein: the first source forms a first spot of the electromagnetic radiation at the first scattering medium, so that the electromagnetic radiation, transmitted from the first spot and scattered through the first scattering medium and the second scattering medium, forms a first speckle pattern comprising one or more first bright speckles at one or more first locations and one or more first dark speckles at one or more second locations; the second detector detects one or more of the speckles at one or more of the locations; the intensity modulator receiving data comprising a data stream of one or more bits comprising one or more “ones” and one or more “zeros,” forms at least one of: one or more second spots of electromagnetic radiation representing the “ones” at each of one or more of the first locations, so that the electromagnetic radiation, transmitted from the one or more second spots and scattered through the second scattering medium and then the first scattering medium, forms one or more second bright speckles on the first detector; or one or more third spots of the electromagnetic radiation representing the “zeros” at each of the one or more third locations, so that the electromagnetic radiation transmitted from the one or more third spots at the second locations through the second scattering medium and then the first scattering medium, forms one or more second dark speckles on the first detector; and a computer comprising one or more processors implemented in hardware connected to the second detector and constructing the data stream by associating the one or more dark speckles with the “zeros” and the one or more bright speckles with the “ones.” ### Claim 2 (depends on 1) The communication system of claim 1, wherein the first source of electromagnetic radiation comprises a laser or light emitting diode and a lens or mirror focusing the electromagnetic radiation so as to form the first spot. ### Claim 3 (depends on 1) The communication system of claim 1, wherein the first source of electromagnetic radiation comprises a second intensity modulator. ### Claim 4 (depends on 1) The communication system of claim 1, wherein the first spot, the one or more second spots, and the one or more third spots each comprise a point source of the electromagnetic radiation. ### Claim 5 (depends on 1) The communication system of claim 1, further comprising: a first station at a first station location, the first station comprising the first source, the first detector, and the first scattering medium; and a second station at a second station location, the second station comprising the intensity modulator comprising a spatial light modulator, the second detector, and the second scattering medium; wherein the first station comprises a first transmitter comprising the first source and a first receiver comprising the first detector; wherein the second station comprises a second transmitter comprising the intensity light modulator and the second receiver comprises the second detector. ### Claim 6 (depends on 5) The communication system of claim 5, wherein the first station and second station are separated by a line of sight and the electromagnetic radiation is transmitted between the first scattering medium and the second scattering medium along the line of sight. ### Claim 7 (depends on 5) The communication system of claim 5, wherein the first station and second station are separated by an optical fiber and the electromagnetic radiation is transmitted between the first scattering medium and the second scattering medium along the optical fiber. ### Claim 8 (depends on 1) The communication system of claim 1, wherein the scattering medium comprise glass. ### Claim 9 (depends on 1) The communication system of claim 1, wherein the computer arranges the zeros and the ones in the data stream according to the chronological order the second bright speckles and the second dark speckles are detected on the first detector. ### Claim 10 (depends on 1) The system of claim 1, further comprising one or more lenses, mirrors, or collimators focusing or collimating the electromagnetic radiation so as to form the first spot or image the second spots or the third spots on the second scattering medium. ### Claim 11 (depends on 1) The system of claim 1, further comprising a second shield or aperture at an input to the second scattering medium and a first shield at an input to the first scattering medium, the shields or apertures suppressing transmission of noisy electromagnetic radiation that does not comprise the electromagnetic radiation being used to transmit the data stream. ### Claim 12 (depends on 1) The system of claim 1, wherein the detectors comprise an array of pixels and the locations are the locations or address of the pixels on the array that receive the speckles. ### Claim 13 A computer implemented method for communicating, comprising: transmitting electromagnetic radiation from a first source of electromagnetic radiation coupled to a first detector and a first scattering medium; forming a first spot of the electromagnetic radiation at the first scattering medium, so that the electromagnetic radiation, transmitted from the first spot and scattered through the first scattering medium and the second scattering medium, forms a first speckle pattern comprising one or more first bright speckles at one or more first locations and one or more first dark speckles at one or more second locations; detecting, on a second detector, one or more of the speckles at one or more of the locations; receiving, on an intensity modulator, data comprising a data stream of one or more bits comprising one or more “ones” and one or more “zeros,” outputting, from the intensity modulator, at least one of: one or more second spots of electromagnetic radiation representing the “ones” at each of one or more of the first locations, so that the electromagnetic radiation, transmitted from the one or more second spots and scattered through the second scattering medium and then the first scattering medium, forms one or more second bright speckles on the first detector; or one or more third spots of the electromagnetic radiation representing the “zeros” at each of the one or more second locations, so that the electromagnetic radiation transmitted from the one or more third spots at the second locations through the second scattering medium and then the first scattering medium, forms one or more second dark speckles on the first detector; and constructing, using a computer comprising one or more processors implemented in hardware connected to the second detector, the data stream by associating the one or more first dark speckles with the “zeros” and the one or more first bright speckles with the “ones.” ### Claim 14 A computer implemented system, comprising: a computer comprising one or more processors implemented in hardware; one or more memories; and one or more programs stored in the one or more memories, wherein the one or more programs executed by the one or more processors performs a method, comprising: constructing a data stream by associating each of one or more dark speckles with a “zero” and each of one or more bright speckles with a “one,” the dark speckles and the bright speckles obtained by a process comprising: transmitting electromagnetic radiation from a first source of electromagnetic radiation coupled to a first detector and a first scattering medium; forming a first spot of the electromagnetic radiation at the first scattering medium, so that the electromagnetic radiation, transmitted from the first spot and scattered through the first scattering medium and a second scattering medium, forms a first speckle pattern comprising the bright speckles comprising one or more first bright speckles at one or more first locations and the dark speckles comprising one or more first dark speckles at one or more second locations; detecting, on a second detector, one or more of the speckles at one or more of the locations; receiving, on an intensity modulator, data comprising a data stream of one or more bits comprising the one or more “ones” and the one or more “zeros,” outputting, from the intensity modulator, at least one of: one or more second spots of electromagnetic radiation representing the “ones” at each of one or more of the first locations, so that the electromagnetic radiation, transmitted from the one or more second spots and scattered through the second scattering medium and then the first scattering medium, forms the bright speckles comprising one or more second bright speckles on the first detector; or one or more third spots of the electromagnetic radiation representing the “zeros” at each of the one or more second locations, so that the electromagnetic radiation transmitted from the one or more third spots at the second locations through the second scattering medium and then the first scattering medium, forms the dark speckles comprising one or more second dark speckles on the first detector. ### Claim 15 (depends on 14) The system of claim 14, wherein the computer constructs a message comprising the data stream, wherein the message is transmitted from a second station in a communications system comprising: a first station at a first station location, the first station comprising the first source, the first detector, and the first scattering medium; and the second station at a second station location, the second station comprising the intensity modulator comprising a spatial light modulator, the second detector, and the second scattering medium; wherein the first station comprises a first transmitter comprising the first source and a first receiver comprising the first detector; and wherein the second station comprises a second transmitter comprising the spatial light modulator and the second receiver comprises the second detector. ### Claim 16 (depends on 15) The system of claim 15, wherein the first station and second station are separated by a line of sight and the electromagnetic radiation is transmitted between the first scattering medium and the second scattering medium along the line of sight. ### Claim 17 (depends on 15) The system of claim 15, wherein the first station and second station are separated by an optical fiber and the electromagnetic radiation is transmitted between the first scattering medium and the second scattering medium along the optical fiber. ### Claim 18 (depends on 14) The system of claim 14, wherein the scattering medium comprise glass. ### Claim 19 (depends on 14) The system of claim 14, wherein the computer arranges the zeros and the ones in the data stream according to a chronological order the second bright speckles and the second dark speckles are detected on the detector. ### Claim 20 (depends on 14) The communication system of claim 14, wherein the first source of electromagnetic radiation comprises a second intensity modulator; and the first spot, the one or more second spots, and the one or more third spots each comprise a point source of the electromagnetic radiation.