Backhaul Signaling for Interference Avoidance in Wireless Networks
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In wireless communication systems, unplanned or semi-planned deployments of access points lead to increased air signal interference, which existing methods struggle to manage effectively, especially in heterogeneous networks where low-power access points are affected by high-power transmitters, resulting in inefficient resource utilization and poor link performance.
Innovation Solution
The implementation of backhaul signaling for interference avoidance, where access points can request reduced transmit power from interfering access points, facilitating dynamic partitioning of signal strengths and resources through a backhaul network to mitigate interference.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If unplanned or semi-planned access point deployments are used, then network deployment flexibility and speed are improved, but air signal interference increases
Solution Approach 1:
The patent implements a feedback mechanism where access points monitor air signal interference levels and automatically send requests through the backhaul network to interfering access points to reduce their transmit power. This closed-loop feedback system enables dynamic interference management that adapts to changing network conditions, resolving the contradiction by allowing flexible deployments while actively managing the resulting interference through continuous monitoring and coordination.
Solution Approach 2:
The backhaul network serves as an intermediary between access points, enabling them to communicate interference levels and coordinate power adjustments without direct air interface interaction. This intermediary communication channel allows access points in unplanned deployments to manage interference effectively by relaying information and coordination messages, thus maintaining deployment flexibility while reducing harmful interference through centralized coordination.
2Power
If high-power transmitters are deployed, then coverage area and signal strength are improved, but interference to low-power access points increases
Solution Approach 1:
The patent implements dynamic transmit power adjustment where high-power access points can receive requests through the backhaul network to reduce their power levels in specific time-frequency resources. This dynamic adaptation allows the system to optimize coverage and signal strength when needed while reducing interference to low-power access points during periods of high interference, resolving the contradiction through time-varying power control based on real-time network conditions.
Solution Approach 2:
The patent enables local quality adjustment where high-power access points can maintain high transmit power in directions and resources where it provides beneficial coverage, while reducing power in specific spatial directions or frequency resources where it causes harmful interference to low-power access points. This localized power control resolves the contradiction by optimizing power distribution spatially and spectrally rather than applying uniform power reduction.
3Object-affected harmful factors
If transmit power is reduced to avoid interference, then interference levels are improved, but link performance and coverage may deteriorate
Solution Approach 1:
The patent implements periodic action through time-division multiplexing where access points alternately transmit at high power and reduced power levels in different time slots. During high-power transmission periods, coverage and link performance are optimized, while during reduced-power periods, interference to neighboring access points is minimized. This periodic power adjustment resolves the contradiction by separating the conflicting requirements in the time domain, ensuring both good link performance and low interference levels are achieved at different times.
Data Source
AI summary
Providing for interference reduction and/or avoidance utilizing backhaul signaling between wireless access points (APs) of a wireless access network (AN) is described herein. By way of example, an interference avoidance request (IAR) can be issued by an AP to reduce signal interference on forward link (FL) and/or downlink (DL) transmissions by neighboring APs. The IAR can be routed via a backhaul network and/or over-the-air via access terminals (ATs) coupled with the AP or one or more interfering APs. Upon receiving the IAR, an interfering AP can determine reduced transmit power levels for FL and/or RL transmissions and respond to the IAR. The response can include reduced power levels and can be sent via the backhaul network or OTA. By employing the backhaul network in full or in part, interference avoidance can be conducted even for semi-planned or unplanned heterogeneous networks coupled by the backhaul.