Derivative works — US Patent 11431431

DEFENSIVE DISCLOSURE

Title: Methods and Apparatus for Dynamic Power-Level Adjustment in Signal Distribution Networks Based on Connected Device Characteristics

Publication Date: May 8, 2026

Abstract: This disclosure describes a series of methods and systems for dynamically adjusting the power level of a signal (e.g., optical, electrical, laser, wireless) that is distributed from a central node to one or more connected endpoint devices. A controller at the distribution node receives or determines connection information identifying the type or operational state of a connected device. Based on this information, the controller adjusts a variable attenuator or amplifier in the signal path to provide a power level specifically optimized for that device. This enables flexible, reconfigurable, and robust networks. The following derivatives and applications are disclosed to place this technology and its foreseeable variations into the public domain.

Derivative Set 1: Material and Component Substitution

This set of derivatives describes alternative physical implementations of the core components (attenuator, controller) to achieve the same functional outcome of device-adaptive signal power control.

1.1. MEMS-based Attenuation Array

Enabling Description: The variable optical attenuator is implemented using a monolithic Micro-Electro-Mechanical System (MEMS) device. An input wavelength-multiplexed signal is demultiplexed and each wavelength is directed to an individual MEMS micromirror. The controller, upon receiving connection information for the device associated with that wavelength's destination port, applies a precise voltage to the corresponding micromirror's actuator. This voltage causes a controlled tilt in the mirror, inducing a calibrated amount of coupling loss as the light is reflected toward the output fiber. The attenuation is thus a function of the tilt angle. The entire array can be fabricated on a single silicon substrate, offering high-speed (microsecond-scale) attenuation changes and high port density.

Diagram:

graph TD
    subgraph MEMS Attenuator Chip
        A[Input WDM Signal] --> B{Demux};
        B --> C1[λ1 → Mirror1];
        B --> C2[λ2 → Mirror2];
        B --> C3[λN → MirrorN];
        C1 --> D1[Output Port 1];
        C2 --> D2[Output Port 2];
        C3 --> D3[Output Port N];
    end
    subgraph Control System
        E[Connection Info for Port 2] --> F[Controller];
        F -- Voltage Signal --x G{Actuator for Mirror2};
    end
    G -. Tilts Mirror .-> C2;

1.2. Semiconductor Optical Amplifier (SOA) in Attenuation Mode

Enabling Description: A Semiconductor Optical Amplifier (SOA) is used as a bi-modal component for both amplification and attenuation. The controller receives connection information for a target device. If the device requires a signal power lower than the demultiplexed input, the controller applies a low forward bias or a reverse bias current to the SOA in that signal's path. This causes the SOA to operate in an absorptive regime, attenuating the signal. The degree of attenuation is directly proportional to the applied current. If the device requires amplification, the controller applies a high forward bias current. This architecture provides a wider dynamic range of power control than a passive attenuator.

Diagram:

sequenceDiagram
    participant Client as Network Mgmt
    participant Node as Controller
    participant SOA as SOA Component
    Client->>Node: Connection Info (Device requires -10dBm)
    Node->>Node: Calculate required attenuation
    Node->>SOA: Set Reverse Bias Current (e.g., -5mA)
    SOA-->>Node: Ack
    Note right of SOA: SOA absorbs photons, acting as attenuator
    Node-->>Client: Port configured

1.3. FPGA-based Controller with In-Field Updatability

Enabling Description: The controller is implemented on a Field-Programmable Gate Array (FPGA) rather than a fixed-function ASIC or microcontroller. The FPGA holds a dynamically updatable look-up table (LUT) in its Block RAM, which maps hundreds of potential "Device Type" identifiers to specific attenuation values and component control parameters (e.g., SOA bias current, MEMS voltage). When a network manager needs to support a new device type, they can push a new bitstream or just the updated LUT to the FPGA remotely, without a physical hardware swap. This allows the optical device to adapt to future, yet-to-be-invented transceivers and client devices.

Diagram:

graph LR
    A[Network Admin] -- New Device Profile --> B(Network Management System);
    B -- Bitstream/LUT Update --> C{FPGA Controller};
    subgraph Optical Node
        D[Pluggable Module<br/><i>New Device Type</i>] -- I2C --> C;
        C -- Fetches new profile --> E[Block RAM LUT];
        E -- Attenuation Value --> C;
        C -- Control Signal --> F(Variable Attenuator);
    end

Derivative Set 2: Operational Parameter Expansion

This set explores the application of the core technology in extreme operational environments.

2.1. Cryogenic Optical Switch for Quantum Computing

Enabling Description: The apparatus is integrated into a dilution refrigerator for routing optical control signals to qubits or quantum sensors. All optical components (demux, attenuators) are fabricated from materials suitable for cryogenic operation (e.g., silicon nitride waveguides). The controller, located outside the refrigerator, adjusts the attenuation based on the connected "device," which could be a specific type of superconducting nanowire single-photon detector (SNSPD) or a quantum dot with distinct optical power requirements. The controller utilizes pre-calibrated maps that account for the temperature-dependent performance of both the attenuator and the receiving quantum device to ensure precise photon delivery.

Diagram:

stateDiagram-v2
    [*] --> Idle
    Idle --> Configuring: Received Qubit_Control_Request
    Configuring --> Active: Attenuation set for SNSPD
    state Configuring {
        direction LR
        [*] --> GetDeviceInfo
        GetDeviceInfo --> LookUpTempMap: Device=SNSPD, Temp=100mK
        LookUpTempMap --> SetAttenuation: Value= -30.5 dB
        SetAttenuation --> [*]
    }
    Active --> Idle: Control Sequence Complete

2.2. High-Power Industrial Laser Beam Distribution

Enabling Description: In a laser manufacturing cell, a central high-power fiber laser (e.g., 20kW) is split into multiple process beams. The disclosed apparatus functions as the beam distribution and power setting node. The "demultiplexer" is a diffractive optical element, and the "attenuator" is an acousto-optic modulator (AOM). The "connected devices" are various tool heads: a welding head, a cutting nozzle, or a surface cladding tool. The central factory controller sends "connection information" identifying the active tool. The node controller then sets the RF power to the AOM to diffract a precise percentage of the laser power, thus attenuating the beam to the exact wattage required for the specific manufacturing process (e.g., 5kW for cutting, 1.5kW for welding).

Diagram:

graph TD
    A[20kW Master Laser] --> B{Beam Splitter/Demux};
    B -- Beam 1 --> C1(AOM 1);
    B -- Beam 2 --> C2(AOM 2);
    C1 --> D1[Welding Head];
    C2 --> D2[Cutting Nozzle];
    E[Factory Controller<br/><i>Job: Weld Seam_A</i>] --> F(Node Controller);
    F -- Sets RF Power for 1.5kW --> C1;

Derivative Set 3: Cross-Domain Application

This set describes the application of the core mechanism in industries unrelated to telecommunications.

3.1. Aerospace: Fly-by-Light Actuator Control

Enabling Description: In a fly-by-light aircraft, optical fibers replace electrical wiring for flight control signals. A node based on this disclosure is placed in an avionics bay to distribute signals from the flight control computer to wing actuators. The "connected devices" are different types of actuators, such as a primary electro-hydraulic actuator and a secondary electro-mechanical backup. The backup actuator may have a more sensitive optical receiver. When the flight computer switches to the backup, it sends connection information identifying the new target. The node controller automatically increases the attenuation on that fiber link to prevent oversaturating the backup actuator's receiver, ensuring its stable operation.

Diagram:

sequenceDiagram
    participant FCC as Flight Control Computer
    participant Node as Optical Node Controller
    participant Actuator as Primary Actuator
    participant Backup as Backup Actuator
    FCC->>Node: Route signal to Primary Actuator
    Node->>Actuator: Optical Signal (-5dBm)
    FCC->>Node: FAULT! Reroute to Backup Actuator
    Node->>Node: Look up profile for Backup
    Node->>Backup: Optical Signal (-15dBm)
    Note right of Backup: Attenuation increased to prevent saturation

3.2. AgTech: Adaptive Lighting in Vertical Farms

Enabling Description: A central LED driver distributes power-over-fiber to multiple LED lighting arrays in a vertical farm. The apparatus acts as a power distribution hub. The "connected devices" are different lighting arrays tailored for various plants (e.g., "Leafy Greens Array," "Fruiting Plants Array," "Seedling Germination Array"). Each array has a different optimal light intensity (PPFD) and power draw. When an array is connected, it identifies itself to the controller, which then adjusts the attenuation of the optical power signal to deliver the precise intensity for the specific plant growth stage, optimizing energy use and crop yield.

Diagram:

erDiagram
    FARM_CONTROLLER ||--o{ LIGHTING_NODE : controls
    LIGHTING_NODE ||--|{ PORT : has
    PORT }o--|| LED_ARRAY : connects_to
    LED_ARRAY {
        string type "Device Type (e.g., 'Leafy Greens')"
        string required_power
    }
    PORT {
        int port_id
        float attenuation_level "Set by Controller"
    }

Derivative Set 4: Integration with Emerging Technology

This set describes integrating the core patent with AI, IoT, and blockchain.

4.1. AI-Driven Predictive Attenuation Maintenance

Enabling Description: The controller integrates a trained machine learning model (e.g., a gradient-boosted tree) that predicts the future health of the optical link. The controller monitors IoT sensor data from the connected device, such as its receiver's bit error rate (BER), temperature, and optical power received, over time. The ML model uses this time-series data to predict degradation due to component aging or fiber strain. It then proactively and gradually adjusts the attenuation (e.g., slightly decreasing it over months) to maintain a constant signal quality at the receiver, maximizing link lifetime and preventing outages.

Diagram:

flowchart LR
    subgraph IoT Device
        A[Optical Receiver]
    end
    subgraph Optical Node
        B[Controller + ML Model]
        C[VOA]
    end
    A -- Telemetry (BER, Temp, Power) --> B;
    B -- Analyzes Trend --> B;
    B -- "Predicts 0.1dB degradation over next month" --> B;
    B -- "Adjust VOA by +0.1dB" --> C;
    C -- Attenuated Signal --> A;

4.2. Blockchain-Verified Device Onboarding and Configuration

Enabling Description: The process of authenticating a connected device and configuring its port is secured by a private blockchain. Each manageable device (pluggable transceiver, client device) is provisioned at the factory with a unique cryptographic identity on the blockchain. When plugged into a port, the device performs a challenge-response handshake with the node controller. The controller verifies the device's identity against the blockchain ledger and retrieves its immutable operational parameters, including its required power class. The controller then sets the attenuation and logs the event (Port ID, Device ID, Attenuation Value, Timestamp) as a new, non-repudiable transaction on the chain, creating a secure audit trail for all network modifications.

Diagram:

sequenceDiagram
    participant Device
    participant Controller
    participant Blockchain
    Device->>Controller: Hello, I am Device_X [sends cert]
    Controller->>Blockchain: Verify(Device_X_cert)
    Blockchain-->>Controller: Verified. Profile: {PowerClass: 4}
    Controller->>Controller: Set Attenuation for PowerClass 4
    Controller->>Blockchain: Log Transaction(Port_5, Device_X, -12dB)
    Blockchain-->>Controller: Transaction Confirmed

Derivative Set 5: The "Inverse" or Failure Mode

This set describes versions of the invention designed for safe failure or limited functionality.

5.1. Fail-Safe Optical Cut-off

Enabling Description: The variable optical attenuator is designed to fail in a known, safe state. It uses a normally-closed MEMS shutter or a liquid crystal cell that is opaque without power. Upon controller failure or power loss to the node, the attenuator automatically reverts to a state of maximum attenuation (>40 dB), effectively blocking the optical signal. This prevents a high-power, un-attenuated signal from propagating downstream and potentially damaging a sensitive receiver on a connected device. An independent watchdog timer in the power circuit can trigger this state if the controller software hangs.

Diagram:

stateDiagram-v2
    state "Active" as Active
    state "Safe Mode" as Safe

    [*] --> Active: Power On
    Active --> Safe: Controller Failure OR Power Loss
    Safe --> Active: System Reset

    state Active {
        direction LR
        [*] --> Attenuating
        Attenuating: Controller sets VOA to -10dB
    }
    state Safe {
        direction LR
        [*] --> MaxAttenuation
        MaxAttenuation: VOA defaults to > -40dB (Signal blocked)
    }

Combination with Open-Source Standards

1. NETCONF/YANG Integration: The system is managed using the IETF NETCONF protocol (RFC 6241). The capabilities of the optical node, including the per-port attenuation settings and device type identification, are formally defined in a YANG data model (RFC 7950). A network management system identifies a newly connected device (e.g., via LLDP), consults its YANG model to determine the device type, and sends a <edit-config> operation to the node, setting the attenuation leaf in the model to a value appropriate for the identified device-type enumeration.
2. MSA-based Plug-and-Play: The "connection information" is acquired by the controller via the I2C management interface defined in open, multi-source agreements (MSAs) for pluggable optics, such as CMIS for QSFP-DD or OSFP modules. The controller reads a standard field from the module's EEPROM, such as the "Power Class" or "Application Code" fields. This code is used as a key to a local table to determine the correct attenuation setting, rendering the invention an obvious implementation detail of existing hot-pluggable hardware standards.
3. Control via gRPC/Protobuf API: The controller hosts a gRPC server defined by an open-source Protocol Buffers (.proto) file. The definition includes a service like OpticalNodeManager with an RPC SetPortConfig(PortInfo) returns (Status). The PortInfo message contains a device_type field, which is a Protobuf enum listing known device categories (e.g., DEVICE_TYPE_LR4, DEVICE_TYPE_ZRPLUS). A remote management system acts as a gRPC client, calling this RPC to configure the port's attenuation based on the device it intends to connect. This decouples the management system from the node hardware, using common open-source RPC technology.