Derivative works — US Patent 8593358

Defensive Disclosure: Derivatives of U.S. Patent 8,593,358

Publication Date: May 13, 2026
Reference ID: DPD-8593358-01

This document discloses technical variations and novel applications derived from the core concepts of U.S. Patent 8,593,358, "Active antennas for multiple bands in wireless portable devices." The purpose of this disclosure is to place these concepts into the public domain, thereby establishing prior art against future patent applications claiming these or obvious variations thereof. The core concept involves a shared, tunable antenna structure for simultaneous multi-band operation.

Derivatives Based on Core Claim 1: Shared Tunable Antenna Array

1. Material & Component Substitution

Derivative 1.1: Graphene-Based Frequency Agile Surface
- Enabling Description: The antenna array elements are fabricated from chemical vapor deposition (CVD) grown monolayer graphene sheets on a silicon dioxide (SiO2) substrate. Tuning is achieved by electrostatically gating the graphene elements. Applying a variable DC bias voltage between the graphene and a back-gate alters the material's Fermi level, which in turn changes its surface conductivity and complex permittivity at RF frequencies. This allows for continuous, non-mechanical tuning of the antenna's resonant frequency. Each element can be individually gated by a multi-channel digital-to-analog converter (DAC) controlled by the device's baseband processor, enabling simultaneous resonance at, for example, 2.4 GHz for Wi-Fi and 28 GHz for 5G mmWave by creating distinct high-conductivity zones on a single antenna surface.
- ```
graph TD
    A[Baseband Processor] -->|Digital Control Bus| B(Multi-channel DAC);
    B -->|V_gate1| C{Graphene Element 1};
    B -->|V_gate2| D{Graphene Element 2};
    subgraph Antenna Array
        C;
        D;
    end
    C -->|RF_out1 @ 2.4GHz| E[Transceiver 1];
    D -->|RF_out2 @ 28GHz| F[Transceiver 2];
```
Derivative 1.2: Liquid Metal Parasitic Elements
- Enabling Description: The primary driven antenna element is a conventional dipole. It is surrounded by an array of microfluidic channels embedded in a polydimethylsiloxane (PDMS) substrate. These channels are filled with a eutectic gallium-indium (EGaIn) alloy. A series of micro-pumps, controlled by the tuner logic, alters the geometry and length of the liquid metal columns within the channels. These columns act as tunable parasitic elements, coupling with the driven element to shift its resonant frequency and radiation pattern. By precisely controlling the shape of multiple parasitic elements, the antenna can be matched to several bands simultaneously.
- ```
sequenceDiagram
    participant C as Controller
    participant P as Micro-pumps
    participant LM as Liquid Metal Elements
    participant Ant as Driven Antenna
    C->>P: Set Channel Geometries (Band 1, Band 2)
    P->>LM: Inject/Retract EGaIn Alloy
    LM->>Ant: Parasitically Couple
    Ant-->>C: Feedback (VSWR)
```

2. Operational Parameter Expansion

Derivative 1.3: Cryogenic Quantum Interface Antenna
- Enabling Description: This device operates within a dilution refrigerator at temperatures below 100 millikelvin for interfacing with superconducting quantum bits (qubits). The antenna array is fabricated from niobium nitride (NbN) on a high-purity silicon substrate. The "tuners" are composed of an array of Superconducting Quantum Interference Devices (SQUIDs). The controller applies a minute magnetic flux to each SQUID loop, which precisely alters its Josephson inductance. This change in inductance is used to tune the impedance of the feedline for each antenna element, allowing for simultaneous, high-fidelity readout of multiple qubits operating at slightly different frequencies in the 4-8 GHz range.
- ```
graph TD
    subgraph Quantum Processor @ <100mK
        Q1(Qubit 1 @ 6.1 GHz) --- A1(NbN Antenna 1);
        Q2(Qubit 2 @ 6.2 GHz) --- A2(NbN Antenna 2);
    end
    subgraph Tuner Array
        T1{SQUID Tuner 1}
        T2{SQUID Tuner 2}
    end
    A1 --- T1;
    A2 --- T2;
    C[Flux Bias Controller] -->|Flux 1| T1;
    C -->|Flux 2| T2;
    T1 --- R1[Readout Rx 1];
    T2 --- R2[Readout Rx 2];
```

3. Cross-Domain Application

Derivative 1.4: Agricultural Smart-Dust Network
- Enabling Description: The wireless device is a millimeter-scale sensor node ("smart dust") dispersed over an agricultural field. The antenna is a single, miniaturized fractal antenna. The device integrates multiple transceivers: a LoRa transceiver (915 MHz) for low-power, long-range communication of soil moisture data and a Bluetooth Low Energy (BLE) transceiver (2.4 GHz) for high-bandwidth communication with aerial drones during fly-overs for firmware updates or data dumps. The tuner consists of a bank of MEMS switched capacitors. The controller, an ultra-low-power MCU, activates the LoRa band for hourly check-ins. When a drone's BLE signal is detected, the controller reconfigures the MEMS switches to tune the antenna to 2.4 GHz for the duration of the high-speed link.
- ```
stateDiagram-v2
    [*] --> LowPower_LoRa
    LowPower_LoRa: Transmitting soil data @ 915 MHz
    LowPower_LoRa --> DroneDetect : Drone signal detected
    DroneDetect --> HighSpeed_BLE : Re-tune antenna to 2.4 GHz
    HighSpeed_BLE: Downloading firmware
    HighSpeed_BLE --> LowPower_LoRa : Drone departs
```
Derivative 1.5: Aerospace Conformal Skin Antenna
- Enabling Description: The "antenna array" is integrated into the composite skin of an aircraft. The radiating elements are conductive carbon nanotube (CNT) fibers woven directly into the carbon-fiber-reinforced polymer (CFRP) fuselage. The device shares this single physical aperture for multiple functions: Ka-band satellite communications (26.5-40 GHz), X-band weather radar (8-12 GHz), and L-band GPS reception (1.575 GHz). Tuning is achieved using embedded phase-shifters and tunable band-stop filters based on Barium Strontium Titanate (BST) thin films, controlled by the central avionics computer. The controller applies bias voltages to the BST elements to create transparent or reflective states for different frequency bands, effectively routing signals from the shared aperture to the correct transceiver.
- ```
flowchart LR
    subgraph Aircraft_Skin
        A(CNT-Fiber Aperture)
    end
    subgraph Avionics_Rack
        T1(GPS Rx)
        T2(Radar XCVR)
        T3(Satcom XCVR)
    end
    A -- L, X, Ka Bands --> F(BST Tunable Filter Bank);
    F -- 1.575 GHz --> T1;
    F -- 8-12 GHz --> T2;
    F -- 26.5-40 GHz --> T3;
    C[Avionics Computer] -- Control Voltages --> F;
```

4. Integration with Emerging Tech

Derivative 1.6: AI-Optimized Cognitive Radio Antenna
- Enabling Description: A neural network, implemented on an edge AI accelerator within the wireless device, acts as the antenna controller. It processes real-time data from an array of IoT sensors (accelerometer, gyroscope, proximity sensor) and RF environment data (signal strength, interference levels). The AI model predictively tunes the antenna array elements before a communication link is established. For example, by sensing the user is raising the phone to their head, it pre-tunes for optimal Specific Absorption Rate (SAR) compliance and signal quality. Tuning is performed by a varactor diode array. The optimal tuning parameters for each context (e.g., "in-pocket", "on-table", "in-hand") are logged to a private blockchain for diagnostics and regulatory reporting.
- ```
graph TD
    subgraph IoT_Sensors
        S1[Accelerometer]
        S2[RF Sniffer]
    end
    subgraph Controller
        AI[Neural Network]
        BC[Blockchain Logger]
    end
    subgraph Tuner
        V(Varactor Diodes)
    end
    S1 & S2 --> AI;
    AI -->|Predictive Tuning Vector| V;
    V -- tunes --> Ant(Antenna Array);
    AI -->|Log Parameters| BC;
```

5. The "Inverse" or Failure Mode

Derivative 1.7: Failsafe Emergency Beacon Mode
- Enabling Description: The tuner circuit is designed with a "dead-man's switch." In case of a power failure to the controller or a detected fault in the tuning components (e.g., a shorted varactor), all electronic tuning elements are galvanically disconnected from the antenna feed via a micro-relay. In this default state, the antenna feed is directly connected to a fixed, passive, broadband impedance matching network. This network provides a suboptimal but functional match across a wide range of emergency frequencies (e.g., VHF marine band and the 406 MHz Cospas-Sarsat satellite beacon band). This ensures the device can transmit a low-power distress signal even when its primary multi-band tuning functionality has failed.
- ```
stateDiagram-v2
    state "Normal Operation" as Normal {
        [*] --> Tuned
        Tuned: Controller actively adjusts tuner for specific bands (LTE, WiFi, etc.)
    }
    state "Failsafe Mode" as Failsafe {
        [*] --> Passive
        Passive: Relay disconnects tuner. Fixed broadband network engaged for emergency frequencies.
    }
    Normal --> Failsafe : Power Loss OR Fault Detected
    Failsafe --> Normal : Power Restored AND System Reset
```

Derivatives Based on Core Claim 14: Simultaneous Multi-Band Matching

Derivative 14.1: Metamaterial-Based Duplexing Antenna
- Enabling Description: The tuner and antenna are integrated into a single metasurface composed of an array of electronically tunable split-ring resonators (SRRs). The multiband transceiver feeds the metasurface at a single point. The controller applies a specific pattern of capacitance values to the varactors integrated into each SRR. This pattern creates two distinct resonant pathways on the surface simultaneously. One pathway is engineered for a low-frequency band (e.g., 1.8 GHz for LTE) and the other for a high-frequency band (e.g., 5.8 GHz for Wi-Fi). The surface provides high isolation between the pathways, allowing the LTE and Wi-Fi transceivers to operate simultaneously from a single feed point without traditional duplexers.
- ```
classDiagram
    class Metasurface {
        +SplitRingResonator[] elements
        +singleFeedPoint
    }
    class SplitRingResonator {
        +varactorDiode
        +capacitanceValue
    }
    class Controller {
        +calculateResonancePattern(band1, band2)
    }
    class Transceiver {
        +transmitLTE()
        +receiveWiFi()
    }
    Controller ..> Metasurface : sets capacitance values
    Transceiver -- Metasurface : single RF connection
```

Combination Prior Art Scenarios

Scenario 1: Integration with GNU Radio (SDR)
- Enabling Description: The controller for the tunable antenna of US 8,593,358 is replaced with a software-defined controller running as a block within the GNU Radio framework on a host computer. The host computer is connected to an SDR peripheral (e.g., a USRP). A custom GNU Radio block, titled "Active Antenna Controller," takes frequency and bandwidth parameters from the SDR signal processing flowgraph as input. It translates these parameters into the required digital control signals (e.g., I2C or SPI commands) for the physical tuner hardware. This allows a user to dynamically re-tune the antenna in real-time from a software flowgraph to seamlessly switch between receiving, for example, an FM broadcast signal at 101.1 MHz and a 4G LTE signal at 1700 MHz using the same hardware.
Scenario 2: Integration with LoRaWAN (IoT Protocol)
- Enabling Description: A wireless IoT device incorporates the tunable antenna system to support multiple regional LoRaWAN standards. A LoRaWAN end-node for global logistics must operate on different ISM bands (e.g., EU868 in Europe, US915 in North America, AS923 in Asia). The device's firmware includes a geolocation module (via GPS or Wi-Fi sniffing). Upon entering a new regulatory region, the controller automatically tunes the single antenna to the correct LoRaWAN frequency plan for that region, ensuring compliance and optimal link performance. The same antenna is simultaneously matched to 2.4 GHz to provide a BLE interface for local configuration by a technician's smartphone.
Scenario 3: Integration with Open-Source Antenna Design (CST/HFSS Models)
- Enabling Description: The physical antenna element described in US 8,593,358 is designed using an open-source model, such as a community-published design for a fractal or patch antenna from a repository like Open-Antenna.org. The design files (e.g., for CST Studio Suite or Ansys HFSS) are made publicly available. The disclosed invention lies in the combination of this open-source physical antenna structure with a specific, proprietary active tuner circuit. The public disclosure provides the simulation model of the open-source antenna and a detailed schematic of the tuner, including component values for the tunable elements (e.g., Skyworks varactor diodes) and the control logic, enabling a person skilled in the art to replicate the combined system for simultaneous multi-band operation.