Network Coding for Wireless Ad Hoc Throughput Bottlenecks

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Wireless ad hoc networks face inefficiencies due to bottlenecks in data transmission, particularly in mesh networks where intermediate nodes can become bottlenecks, limiting the average number of packets received by destination nodes per time slot.

Innovation Solution

The implementation of network coding, where intermediate nodes perform linear combinations of incoming packets and transmit mixed packets, allowing destination nodes to decode the original packets, thereby increasing the throughput by reducing the number of transmissions needed.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If data is forwarded through intermediate nodes in mesh networks, then network coverage and connectivity are improved, but network bottlenecks occur at intermediate nodes limiting throughput

Engineering Contradiction:
Improvenetwork coverageVSAvoidthroughput
Core Design Contradiction:
Adaptability or versatilityVSProductivity

Solution Approach 1:

The patent combines multiple incoming packets into a single network-coded packet at intermediate nodes. Instead of forwarding each packet separately, intermediate nodes perform linear combinations of packets from different sources and forward the combined packet, thereby reducing the number of transmissions required and eliminating bottlenecks while maintaining network coverage.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The patent changes the parameter of packet transmission by applying network coding operations (linear combinations) to packets. This transformation allows intermediate nodes to transmit information more efficiently by encoding multiple packets into fewer transmissions, thereby increasing throughput without sacrificing connectivity.

Inventive Principle:
Principle #35Parameter changes

2Ease of operation

If routing algorithms are used in mesh networks, then packet delivery is achieved, but routing table maintenance and exchange increase system complexity

Engineering Contradiction:
Improvepacket deliveryVSAvoidrouting table maintenance
Core Design Contradiction:
Ease of operationVSDevice complexity

Solution Approach 1:

The patent extracts the complex routing table maintenance requirement from the system by replacing traditional routing algorithms with network coding. Instead of maintaining and exchanging routing tables, intermediate nodes simply apply linear combination operations to incoming packets, significantly reducing system complexity while maintaining packet delivery capability.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent introduces network coding as an intermediary mechanism between packet reception and packet delivery. Rather than using complex routing tables to determine packet forwarding, intermediate nodes use network coding operations to automatically combine and forward packets, simplifying the intermediary function while ensuring delivery.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Productivity

If traditional packet routing is used, then each packet is forwarded individually, but more transmissions are required increasing time slot usage

Engineering Contradiction:
Improvepacket deliveryVSAvoidtime slot usage
Core Design Contradiction:
ProductivityVSLoss of time

Solution Approach 1:

The patent merges multiple individual packet transmissions into a single network-coded transmission. By combining packets from multiple sources into one encoded packet at intermediate nodes, the system reduces the total number of transmissions required, thereby decreasing time slot usage and improving overall productivity.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The patent enables continuous useful action by allowing intermediate nodes to perform network coding operations on packets in real-time as they arrive. This continuous encoding and combining process ensures that transmissions are optimized continuously, reducing idle time slots and maintaining high productivity throughout the network operation.

Inventive Principle:
Principle #20Continuity of useful action

Data Source

PatentEP3342109B1Wireless ad hoc network using network coding
Publication Date: 2020.12.09 MOTOROLA MOBILITY LLC
  • EP3342109B1 patent drawingFigure 1(a)~1(b)
  • EP3342109B1 patent drawingFigure 2
  • EP3342109B1 patent drawingFigure 3

AI summary

A method of operating a wireless ad hoc network includes configuring an intermediate device (u) with a first linear network code (901) corresponding to a first source device (S1) and a second linear network code (902) corresponding to a second source device (S2). The intermediate device (u) is on communication paths from the first source device (S1) and the second source device (S2) to a plurality of destination devices (T1-T6). The intermediate device (u) receives packet data from either the first source device (S1) or from the second source device (S2), and determines whether to apply the first linear network code (901) or the second linear network code (902) to the packet data. The intermediate device (u) generates outgoing packet data and sends the packet data to at least one destination device of the plurality of destination devices (T1-T6) using either the first linear network code (901) or the second linear network code (902).