Single RF Interface Cable Calibration With Loopback Gain Adjustment

Solution Overview

Problem

Modern antenna subsystems using multiple interface cables face installation complexity, high maintenance effort, and significant weight due to numerous interconnections, particularly in aerospace applications, where weight is a critical consideration.

Innovation Solution

A method and apparatus for calibrating a single coaxial cable interface using a satellite data unit (SDU) and built-in processing logic to multiplex signals, reducing the need for multiple cables by employing a calibration unit with loopback paths, detectors, and DSPs to adjust gain automatically.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If multiple interface cables are used to connect antenna subsystems for signal control and conditioning, beam forming and steering, and BITE functions, then the system can accomplish all required functions, but the installation complexity, maintenance effort, and overall system weight increase significantly

Engineering Contradiction:

Improvesystem functionalityVSAvoidinstallation complexity

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent combines multiple separate interface cables into a single cable assembly that carries multiple RF signals simultaneously. The cable assembly includes multiple coaxial cables bundled together with a single connector at each end, allowing multiple signals to be transmitted through one physical connection point rather than requiring separate cable routes and connectors for each signal path.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The single cable assembly is designed to handle multiple functions simultaneously - it carries multiple RF signals for different antenna elements, supports beam forming operations, enables signal control and conditioning, and provides BITE capabilities all through one universal interface connection, replacing what previously required multiple dedicated cables.

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Adaptability or versatility

If multiple interface cables are used to connect antenna subsystems, then all required functions can be accomplished, but the overall system weight becomes significant due to the weight of the cables

Engineering Contradiction:

Improvesystem functionalityVSAvoidsystem weight

Core Design Contradiction:

Adaptability or versatilityVSWeight of stationary object

Solution Approach 1:

The patent combines multiple separate interface cables into a single cable assembly that carries multiple RF signals simultaneously. The cable assembly includes multiple coaxial cables bundled together with a single connector at each end, allowing multiple signals to be transmitted through one physical connection point rather than requiring separate cable routes and connectors for each signal path.

Inventive Principle:

Principle #5Merging (Combining)

3Adaptability or versatility

If multiple interface cables are used to connect antenna subsystems, then all required functions can be accomplished, but the maintenance effort increases due to the number of connections to manage

Engineering Contradiction:

Improvesystem functionalityVSAvoidmaintenance effort

Core Design Contradiction:

Adaptability or versatilityVSEase of repair

Solution Approach 1:

The patent combines multiple separate interface cables into a single cable assembly that carries multiple RF signals simultaneously. The cable assembly includes multiple coaxial cables bundled together with a single connector at each end, allowing multiple signals to be transmitted through one physical connection point rather than requiring separate cable routes and connectors for each signal path.

Inventive Principle:

Principle #5Merging (Combining)

Data Source

PatentUS12526040B2Method and apparatus for calibrating a single antenna RF interface cable

Publication Date: 2026.01.13 AEROANTENNA TECH

AI summary

A calibration unit for calibrating a single cable interface operably coupling an SDU to an antenna includes a calibration loopback path operably coupled to a first path of the antenna and a second path of the antenna, a first path switch and a second path switch operably coupled to the first and second paths of the antenna, respectively, to alternately connect and disconnect the first and second paths of the antenna to the calibration loopback path where the first and second paths of the antenna are operably coupled to a first end of the single cable interface, a first detector operably coupled to a second path of the SDU among a first path of the SDU and the second path of the SDU that are each operably coupled to a second end of the single cable interface, the first detector being configured to detect a first signal at the second path of the SDU, an SDU DSP operably coupled to the first detector, a second detector operably coupled to the first path of the antenna to detect a second signal at the first path of the antenna, and an antenna DSP operably coupled to the second detector. The antenna DSP determines a first gain adjustment based on a test signal inserted at the first path of the SDU and the first signal and the second signal, and the SDU DSP determines a second gain adjustment based on the test signal, the first signal and the second signal.