Active Phased Array Antenna Transmit Power Loss Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional aircraft surveillance systems using passive phased array antennas face limitations in receive system performance, system range, and transmit power efficiency due to high power losses in coaxial transmission lines, resulting in reduced effective radiated power and receive sensitivity.
Innovation Solution
An active antenna system with power amplifiers integrated into the antenna module to increase transmit power levels and low noise amplifiers to enhance receive signal power, eliminating the need for high power amplifiers at the transceiver and reducing noise contributions from transmission lines.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If conventional passive phased array antennas are used with remote transceivers, then system complexity is reduced and ease of manufacture is improved, but transmit power efficiency deteriorates and receive sensitivity is reduced due to high power losses in coaxial transmission lines
Solution Approach 1:
The patent divides the power amplification function into multiple segments by placing individual power amplifiers at each antenna element rather than using a single remote amplifier. This segmentation allows each amplifier to operate at lower power levels locally, reducing transmission losses in the feed lines while maintaining overall system performance.
Solution Approach 2:
The patent introduces active components (power amplifiers and low noise amplifiers) as intermediaries between the transmission lines and antenna elements. These intermediaries compensate for transmission losses by amplifying signals locally, thereby reducing the overall power loss in the system while maintaining manageable complexity through modular integration.
2Length of moving object
If high power amplifiers are placed at the remote transceiver, then transmit range is improved, but power loss in transmission lines increases and receive sensitivity deteriorates
Solution Approach 1:
The patent applies preliminary action by placing power amplifiers at the antenna elements before the signals are transmitted through the air. This allows the full transmit power to be achieved at the antenna without requiring high power amplifiers at the remote transceiver, thereby avoiding transmission line losses while maintaining the required transmit range.
Solution Approach 2:
The patent implements local quality by providing power amplification specifically at the antenna elements where it is most needed, rather than uniformly distributing amplification throughout the system. This localized approach ensures high transmit range at each element while minimizing overall power loss in the transmission infrastructure.
3Measurement precision
If passive phased array antennas are used, then device complexity is reduced, but receive sensitivity is reduced due to noise contributions from transmission lines
Solution Approach 1:
The patent introduces low noise amplifiers as intermediaries at each antenna element to amplify weak received signals before they travel through the transmission lines. This early amplification occurs before the signals are degraded by transmission line noise, thereby improving receive sensitivity while maintaining modular complexity that is manageable through standard integration techniques.
Solution Approach 2:
The patent applies preliminary action by performing signal amplification at the antenna elements before the signals are transmitted through the lossy transmission lines to the receiver. This preliminary amplification ensures that weak signals are strengthened before undergoing transmission, thereby improving receive sensitivity without requiring overly complex receiver infrastructure.
4Ease of operation
If coaxial transmission lines of several feet length are used, then ease of connection is improved, but power loss increases and effective radiated power is reduced
Solution Approach 1:
The patent extracts the power amplification function from the remote transceiver and places it directly at the antenna elements. This extraction eliminates the need for high power transmission through long coaxial lines, allowing the use of shorter or lower-loss transmission lines while maintaining ease of connection through standardized interfaces.
Solution Approach 2:
The patent changes the power level parameter along the transmission path by amplifying signals locally at each antenna element. This parameter change allows the transmission lines to operate at lower power levels, reducing power loss while maintaining connection ease through standard low-power connectors and interfaces.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The active antenna system achieves improved transmit range and receive sensitivity, potentially extending the receive range to 150 to 200 nautical miles while reducing power supply requirements and system complexity.
Implementation Method 1
A power amplifier is provided on the antenna module along the transmit path. The power amplifier increases a power level of the electrical transmit signals, received from the communications link, by a predetermined amount sufficient to drive the antenna element to transmit the RF transmit signals at the predetermined ERP.
Implementation Method 2
An antenna element for transmitting RF transmit signals at a predetermined effective radiated power (ERP)
Implementation Method 3
An antenna element for receiving RF received signals at a receive power level and outputting electrical receive signals based on the RF received signals
Implementation Method 4
An amplifier element is provided on the antenna module along the receive path. The amplifier element increases a power level of the electrical receive signal, received at the antenna element, above the previous element power level before outputting the electrical receive signal from the connector module onto the communications link.
Data Source
AI summary
An active antenna is provided that includes an antenna element for transmitting RF transmit signals at a predetermined effective radiated power (ERP). An antenna module is configured to be mounted to an aircraft, with the antenna element being mounted to the antenna module. A connector module is provided at the antenna module and is configured to be coupled to a communications link and receive electrical transmit signals from the communications link. A transmit path is provided within the antenna module and extends between the antenna element and the connector module. A power amplifier is provided on the antenna module along the transmit path. The power amplifier increases a power level of the electrical transmit signals, received from the communications link, by a predetermined amount sufficient to drive the antenna element to transmit the RF transmit signals at the predetermined ERP.