Adaptive Antenna Null Steering for Interference Avoidance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Multi-station communication networks face challenges in difficult radio environments with low density, cluttered areas, and high interference, leading to compromised connectivity and limited diversity in wireless local area networks (WLANs).
Innovation Solution
The method involves using wireless stations with controllable antenna systems to selectively direct nulls towards interference sources, allowing for dynamic adjustment of radiation patterns to enhance connectivity by steering nulls and beams, thereby increasing diversity in connectivity options and reducing interference.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If stations use fixed radiation patterns in high interference environments, then device complexity is reduced, but connectivity reliability deteriorates due to inability to avoid interference sources
Solution Approach 1:
The patent implements controllable antenna systems that dynamically adjust radiation patterns by steering nulls toward interference sources and beams toward desired signal directions. This dynamic adaptability allows stations to maintain reliable connectivity in high interference environments by real-time optimization of antenna patterns based on detected interference and signal sources.
Solution Approach 2:
The system changes antenna radiation pattern parameters (null directions, beam directions, gain levels) based on environmental conditions. By detecting interference sources and desired signals, the antenna system modifies its radiation characteristics to optimize connectivity while managing complexity through parameter adjustment rather than hardware changes.
2Length of moving object
If stations transmit at higher power levels to overcome path loss and interference, then connectivity range is improved, but energy consumption increases
Solution Approach 1:
The antenna system applies local quality by concentrating transmission energy in specific directions through beam steering toward desired receivers and creating nulls in directions of interference sources. This directional focus improves connectivity range in target directions without requiring uniform high power transmission in all directions, thereby reducing overall energy consumption.
Solution Approach 2:
The system converts the harmful effect of interference into a beneficial directional constraint by steering nulls toward interference sources. This allows the station to achieve better signal-to-interference ratios without increasing transmission power, effectively extending usable connectivity range while maintaining energy efficiency.
3Adaptability or versatility
If stations use omnidirectional antennas to maximize neighbor discovery, then connectivity diversity is improved, but interference from multiple directions increases
Solution Approach 1:
The system dynamically switches between omnidirectional and directional radiation patterns based on operational phase. During neighbor discovery, omnidirectional patterns maximize connectivity diversity. During data transmission, directional patterns with nulls toward interference sources reduce multi-directional interference. This dynamic adaptation resolves the contradiction between diversity and interference reduction.
Solution Approach 2:
The antenna system segments the radiation space by creating directional beams toward desired directions and nulls toward interference directions. This spatial segmentation allows the system to maintain connectivity diversity through multiple directional options while reducing interference by excluding specific directions from active transmission.
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 improves connectivity and reliability in challenging environments by creating diversity in communication paths, allowing for more efficient data transmission and increased range at lower power levels, even in areas with high interference and limited infrastructure.
Implementation Method 1
at least some stations have a controllable antenna system operable to direct a null selectively
Implementation Method 2
operating an antenna system at one or more stations to steer the radiation pattern of the antenna system
Data Source
Figure 1(a)~1(b)
Figure 2
Figure 3
AI summary
A wireless network having multiple levels of receivers and transmitters separated by altitude comprising: a first layer of stations including receivers and transmitters with associated antennas located relatively close to the earth's surface; and, a second layer of stations including receivers and transmitters with associated antennas located above the earth's surface configured to connect with said first layer and with other stations of the second layer.