Derivative works — US Patent 10468047

DEFENSIVE DISCLOSURE: DERIVATIVE WORKS AND NOVEL APPLICATIONS FOR WIRELESS AUDIO SYSTEMS

Publication Date: May 13, 2026

Reference Patent: US 10,468,047 B2, "Wireless digital audio music system"

Disclaimer: This document is a defensive publication intended to place the described concepts into the public domain, thereby establishing prior art. This action is taken to preclude patenting of these concepts by others. No license, expressed or implied, is granted under any patent rights.

Introduction

This defensive disclosure builds upon the foundational teachings of US Patent 10,468,047 B2. The '047 patent describes a portable spread spectrum audio receiver and transmitter system utilizing a unique user code and Code Division Multiple Access (CDMA) for interference-free wireless audio transmission. The core claims focus on a receiver configured to handle various demodulation schemes (including DPSK and non-DPSK), reduce intersymbol interference, and provide a high-fidelity analog audio output. This document explores novel and non-obvious extensions, variations, and applications of the '047 patent's core principles, with the intent of rendering incremental improvements by competitors as obvious.

Analysis of Core Claim 1: A Portable Spread Spectrum Audio Receiver

The fundamental innovation of Claim 1 lies in a portable receiver that can:

Store a unique user code for CDMA-based communication.
Receive and process wireless transmissions to reduce intersymbol interference.
Perform multiple demodulation types, including DPSK.
Exclude audio content from non-paired transmitters.
Convert the digital signal to an analog output for a speaker.

The following sections detail derivative inventions based on this core concept.

Derivative Variations Based on Core Claim 1

1. Material & Component Substitution

1.1. Graphene-Based Shielding and Antenna Components

Enabling Description: The portable receiver's casing and internal shielding are constructed from a graphene-polymer composite. This material provides superior electromagnetic interference (EMI) shielding compared to traditional materials, enhancing the receiver's ability to reject unwanted signals, a key aspect of the original patent. The receiving antenna is fabricated from a printed graphene film, allowing for a more compact and conformal design integrated directly into the headphone housing. This substitution improves signal-to-noise ratio and physical durability.

Mermaid Diagram:

graph TD
    A[Graphene-Polymer Composite Housing] -- Provides EMI Shielding --> B(Internal Circuitry);
    C[Printed Graphene Film Antenna] -- Captures RF Signal --> D(Direct Conversion Module);
    B -- Protects --> D;
    D -- Processes Signal --> E(DAC);
    E -- Outputs Analog Signal --> F(Speaker);

1.2. Ferroelectric RAM for User Code Storage

Enabling Description: The unique user code is stored in Ferroelectric RAM (FeRAM) instead of conventional EEPROM or flash memory. FeRAM offers faster write times and significantly lower power consumption, which is critical for a battery-powered portable device. This allows for dynamic and rapid re-pairing of the receiver with different transmitters, or even "guest" access codes that can be quickly written and erased. The lower power draw extends the operational life of the receiver on a single charge.

Mermaid Diagram:

sequenceDiagram
    participant TX as Transmitter
    participant RX as Receiver
    participant FeRAM
    TX->>RX: Initiate Pairing (with new user code)
    RX->>FeRAM: Write Unique User Code
    Note right of FeRAM: Low-power, high-speed write operation
    FeRAM-->>RX: Confirm Code Storage
    RX-->>TX: Acknowledge Pairing

2. Operational Parameter Expansion

2.1. Cryogenic Temperature Operation for Scientific Instrumentation

Enabling Description: The receiver is adapted for operation in cryogenic environments (e.g., down to 77 Kelvin) for use in scientific and medical imaging applications like MRI or quantum computing labs. The electronic components, including the direct conversion module and DAC, are selected for their low-temperature performance characteristics. The battery is replaced with a supercapacitor bank tolerant of extreme cold. This system would be used to transmit sensor data or audio cues within the shielded, high-interference environment of a superconducting magnet, where wired connections are problematic.

Mermaid Diagram:

stateDiagram-v2
    [*] --> Idle
    Idle --> Receiving: RF Signal Detected
    Receiving --> Processing: Signal Locked
    state Processing {
        [*] --> Demodulation
        Demodulation --> Code_Check
        Code_Check --> DAC_Conversion: User Code Match
        Code_Check --> Idle: Code Mismatch
        DAC_Conversion --> [*]
    }
    Processing --> Idle: Signal Lost
    note right of Processing
        All components rated for 77K operation.
        Supercapacitor power source.
    end note

2.2. High-Frequency, High-Bandwidth Industrial Data Streaming

Enabling Description: The system is scaled up to operate in the 60 GHz frequency band, allowing for multi-gigabit-per-second data rates. This is not for audio, but for streaming high-resolution sensor data (e.g., LiDAR, machine vision) in a noisy industrial automation setting. The core CDMA principle is retained to allow multiple machines on a factory floor to communicate wirelessly without interference. The "unique user code" becomes a unique machine identifier. The receiver is integrated into a programmable logic controller (PLC) or an edge computing device.

Mermaid Diagram:

graph TD
    subgraph Factory_Floor
        A(Robot_1_Transmitter) -- 60GHz_CDMA_Stream --> B(PLC_Receiver_1);
        C(Robot_2_Transmitter) -- 60GHz_CDMA_Stream --> D(PLC_Receiver_2);
        E(Conveyor_Sensor_Transmitter) -- 60GHz_CDMA_Stream --> F(Edge_Compute_Receiver);
    end
    B -- Machine_Data_1 --> G(Central_Control);
    D -- Machine_Data_2 --> G;
    F -- Sensor_Data --> G;

3. Cross-Domain Application

3.1. Aerospace: Intra-Vehicular Wireless Crew Communication

Enabling Description: The system is implemented for astronaut communication inside a spacecraft or habitat. The CDMA and unique user code features are critical for ensuring that private communication channels can be established between crew members without interference from the multitude of other RF systems on board. The receiver is integrated into the helmet of the spacesuit, and the transmitter is a small, battery-powered unit on the crew member's belt. The system is hardened against radiation and designed for high reliability.

Mermaid Diagram:

sequenceDiagram
    participant Commander_TX
    participant Engineer_RX
    participant FlightControl_TX
    Commander_TX->>Engineer_RX: Private Channel (Code 12A)
    FlightControl_TX-->>Engineer_RX: All-Hands Channel (Code 01X) - Heard by all
    Note over Engineer_RX: Receiver processes both, user selects active channel.

3.2. AgTech: In-Field Sensor Network for Precision Farming

Enabling Description: The transmitter is connected to a soil moisture or nutrient sensor, and the receiver is part of a central hub in a farmer's field. Each sensor (or group of sensors) is assigned a unique user code. The CDMA capability allows hundreds of sensors to transmit data simultaneously to the hub without interfering with each other. The hub then aggregates the data and transmits it to the cloud for analysis. The low-power design is essential for long-term deployment in remote fields.

Mermaid Diagram:

erDiagram
    SENSOR {
        int SensorID
        string UserCode
    }
    HUB {
        int HubID
    }
    SENSOR ||--o{ HUB : "Transmits To"

3.3. Consumer Electronics: Multi-User Virtual Reality Audio

Enabling Description: In a multi-user VR arcade or home setup, each player's headset is a receiver, and the VR system is the transmitter. The system uses CDMA to send a unique, personalized audio stream to each player based on their position and actions in the virtual world. This prevents audio crosstalk and ensures an immersive experience. The "unique user code" is assigned to the player's headset when they join the game.

Mermaid Diagram:

graph TD
    VR_System -- User_1_Audio (Code ABC) --> Headset_1;
    VR_System -- User_2_Audio (Code XYZ) --> Headset_2;
    VR_System -- User_3_Audio (Code 123) --> Headset_3;
    Headset_1 -- Ignores --> User_2_Audio;
    Headset_1 -- Ignores --> User_3_Audio;

4. Integration with Emerging Tech

4.1. AI-Driven Dynamic Code and Frequency Hopping

Enabling Description: An AI agent is integrated into the transmitter and receiver. The agent monitors the RF spectrum in real-time and uses a machine learning model to predict and avoid interference. It can dynamically change the "unique user code" (the CDMA spreading code) and the frequency band of the spread spectrum signal to proactively hop away from noisy channels. This creates a cognitive radio system that is far more robust than the static system in the original patent.

Mermaid Diagram:

flowchart LR
    subgraph Receiver
        A[Spectrum_Scanner] --> B{AI_Agent};
        B -- Predicts_Interference --> C[Code/Frequency_Control];
        C -- New_Code --> D[CDMA_Module];
        C -- New_Frequency --> E[Direct_Conversion_Module];
    end
    subgraph Transmitter
        F[Spectrum_Scanner] --> G{AI_Agent};
        G -- Predicts_Interference --> H[Code/Frequency_Control];
        H -- New_Code --> I[CDMA_Module];
        H -- New_Frequency --> J[Transmitter_Module];
    end
    Transmitter --> Receiver;

4.2. IoT-Enabled Environmental-Aware Audio Equalization

Enabling Description: The headphone receiver is equipped with an array of IoT sensors (e.g., microphone, accelerometer, pressure sensor). These sensors provide real-time data about the user's environment (ambient noise level, whether they are running or sitting still, altitude). This data is fed to a local processor that dynamically adjusts the audio equalization. For example, it could boost bass frequencies when high levels of low-frequency ambient noise are detected. The CDMA link remains the core of the audio delivery.

Mermaid Diagram:

graph TD
    A[IoT_Sensors] -- Env_Data --> B(Processor);
    C[Wireless_Receiver] -- Audio_Stream --> B;
    B -- Adjusts_EQ --> D(DAC);
    D -- Equalized_Audio --> E(Speaker);

4.3. Blockchain for Authenticating Transmitters

Enabling Description: Each transmitter is manufactured with a unique cryptographic key stored in a secure element. The "unique user code" is derived from this key. When a receiver pairs with a transmitter, it verifies the transmitter's authenticity by checking its key against a public blockchain ledger. This prevents counterfeit or unauthorized devices from being used with the system, which is critical for secure applications like law enforcement or military communications.

Mermaid Diagram:

sequenceDiagram
    participant TX
    participant RX
    participant Blockchain
    TX->>RX: Pairing Request (with Public Key)
    RX->>Blockchain: Verify Public Key
    Blockchain-->>RX: Verification Result (Success/Fail)
    alt Key is Valid
        RX-->>TX: Pairing Successful
    else Key is Invalid
        RX-->>TX: Pairing Denied
    end

5. The "Inverse" or Failure Mode

5.1. Graceful Degradation to a Low-Power, Mono Audio Mode

Enabling Description: The receiver constantly monitors its battery level. When the battery drops below a critical threshold (e.g., 10%), the system automatically enters a "limp mode." In this mode, it switches from stereo to mono audio, reduces the audio bandwidth (e.g., from 20kHz to 10kHz), and simplifies the demodulation scheme to a less computationally intensive one (e.g., from DPSK to a simpler FSK). This significantly reduces power consumption, allowing the user to continue listening for an extended period, albeit at a lower quality.

Mermaid Diagram:

stateDiagram-v2
    state Full_Power {
        Stereo_Audio
        Wide_Bandwidth
        DPSK_Demodulation
    }
    state Low_Power {
        Mono_Audio
        Narrow_Bandwidth
        FSK_Demodulation
    }
    [*] --> Full_Power
    Full_Power --> Low_Power: Battery < 10%
    Low_Power --> [*]: Power Off

Combination Prior Art Scenarios

Combination with Bluetooth Low Energy (BLE) Standard: The core CDMA audio transmission of the '047 patent is used for the high-bandwidth audio stream. However, the initial pairing, user code exchange, and control signals (play, pause, volume) are handled over a standard Bluetooth Low Energy (BLE) connection. This leverages the ubiquitous BLE for low-power control while using the patented method for high-quality, low-latency audio, which BLE Audio protocols may not achieve in high-interference environments.
Combination with WebRTC Open Source Project: A transmitter device, instead of connecting to a local audio source, connects to a web browser and uses the WebRTC API to receive an audio stream from the internet. The transmitter then re-encodes this stream using the CDMA and unique user code method from the '047 patent to broadcast it to a local receiver. This creates a bridge between a global, web-based audio source and a local, interference-resistant wireless listener.
Combination with the Advanced Audio Coding (AAC) Open Standard: The system as described in the '047 patent uses a generic analog-to-digital conversion. This is enhanced by first encoding the audio using the open AAC standard before the CDMA modulation. The receiver then performs the inverse operation: after demodulation and CDMA decoding, it uses a standard AAC decoder to reconstruct the audio signal before the final digital-to-analog conversion. This significantly improves audio quality for a given bit rate compared to uncompressed digital audio.