Antenna Array Beamfocusing and Nulling via Covariance Weighting
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current multiple antenna configurations in wireless communications face challenges in maintaining signal coherency at specific locations while nulling signals at other locations, due to interference and coordination issues.
Innovation Solution
A method and system that manipulate signals from multiple antennas to achieve beamfocusing at desired locations by generating a weight vector that enhances signal coherence and introduces a nulling component to cancel signals at undesired locations, using a covariance matrix and Hermitian transpose calculations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If multiple antennas are used to increase transmission bandwidth and signal power, then the ability to combine signals to transmit farther in a particular direction is improved, but interference between the multiple antennas and coordination issues worsen
Solution Approach 1:
The patent combines signals from multiple antennas using beamforming techniques, where signals from multiple antennas are coherently combined to achieve constructive interference in desired directions and destructive interference in unwanted directions. This merging of signals increases transmitted power in specific directions while managing interference through coordinated phase and amplitude adjustment.
Solution Approach 2:
The patent employs adaptive beamforming that dynamically adjusts parameters such as phase shifts, amplitude weights, and beam directions based on channel conditions and interference patterns. By changing these parameters in real-time, the system optimizes signal power in desired directions while suppressing interference, resolving the contradiction between power enhancement and coordination complexity.
2Length of moving object
If multiple antennas are used to transmit signals farther in a particular direction, then signal transmission distance is improved, but the ability to null signals in other directions becomes insufficient
Solution Approach 1:
The patent implements spatially selective signal processing where different beamforming weights and phases are applied to different antenna elements based on the desired radiation pattern. This creates localized signal enhancement in specific directions (main beams) and localized nulling in other directions, allowing the system to transmit farther in desired directions while simultaneously suppressing interference in unwanted directions.
Solution Approach 2:
The patent converts the potentially harmful interference between antenna elements into a beneficial effect by using constructive and destructive interference principles. By carefully controlling the phase and amplitude of signals from each antenna, the system creates constructive interference in desired directions (extending transmission distance) and destructive interference in unwanted directions (nulling signals), thus converting interference from a harmful factor into a useful tool for spatial signal control.
3Reliability
If beamforming weights are adjusted to focus signals at specific locations, then signal coherency at desired locations is improved, but signal nulling at other locations becomes more difficult
Solution Approach 1:
The patent extends traditional beamforming from direction-only control to three-dimensional spatial control by incorporating range information and creating spatial nulls at specific locations. By using spherical coordinate systems and range-dependent phase compensation, the system can focus signals at specific (azimuth, elevation, range) locations while creating nulls at other specific locations, adding a dimensional aspect to the beamforming control that simultaneously improves coherency and nulling capability.
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
This approach effectively provides a stronger, more focused signal at desired locations while minimizing signal reception at other locations, improving signal quality and reducing interference.
Implementation Method 1
the ability to combine signals from the multiple antennas to increase power and transmit a signal farther in a particular direction... and to null the transmitted signal in another direction
Data Source
Figure 1
Figure 2
Figure 3
AI summary
In an antenna array, signals may be manipulated to increase coherency at certain locations (beamfocusing) and reduce or cancel the signals at other locations (nulling). This is accomplished by multiplying the signals received or transmitted by the set of antennas by a weight vector that is generated by determining a covariance matrix based on a vector representing signals at the set of antennas, vectors representing the desired beamfocusing and nulling locations, and a desired nulling depth.