Multi-Channel RoT Threshold Segmentation for M2M Link Budget

Solution Overview

Problem

In machine-to-machine (M2M) wireless wide area networks, the existing approaches to setting noise and interference thresholds for reverse link communications are inadequate, leading to communication problems due to high interference levels, which can prevent devices with larger path loss from transmitting effectively while diminishing the capacity of frequency channels.

Innovation Solution

The solution involves dividing the operating frequency band into multiple reverse link frequency channels with distinct 'rise over thermal' (RoT) thresholds, allowing for dynamic adjustment based on the number of devices using each channel and their signal strength, with a low RoT threshold reserved for devices with larger path loss to ensure communication while maintaining channel capacity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If a single high RoT threshold is set for all frequency channels, then channel capacity is increased, but M2M devices with larger path loss cannot transmit effectively

Engineering Contradiction:

Improvechannel capacityVSAvoidtransmission reliability for devices with large path loss

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The frequency band is divided into multiple frequency channels, each with its own RoT threshold. This segmentation allows different RoT thresholds to be applied to different channels, enabling M2M devices with large path loss to use channels with lower RoT thresholds while maintaining high channel capacity overall.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different RoT thresholds are assigned to different frequency channels based on local conditions. Channels with lower RoT thresholds are allocated to serve M2M devices with large path loss, while other channels maintain higher thresholds for maximum capacity, creating localized optimization throughout the frequency band.

Inventive Principle:

Principle #3Local quality

2Reliability

If a single low RoT threshold is set for all frequency channels, then M2M devices with larger path loss can transmit effectively, but channel capacity is diminished

Engineering Contradiction:

Improvetransmission reliability for devices with large path lossVSAvoidchannel capacity

Core Design Contradiction:

ReliabilityVSProductivity

Solution Approach 1:

The frequency band is divided into multiple frequency channels, each with its own RoT threshold. This segmentation allows different RoT thresholds to be applied to different channels, enabling M2M devices with large path loss to use channels with lower RoT thresholds while maintaining high channel capacity overall.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different RoT thresholds are assigned to different frequency channels based on local conditions. Channels with lower RoT thresholds are allocated to serve M2M devices with large path loss, while other channels maintain higher thresholds for maximum capacity, creating localized optimization throughout the frequency band.

Inventive Principle:

Principle #3Local quality

3Reliability

If high power transmissions are used by M2M devices, then transmission reliability is improved, but interference levels become too high for the network

Engineering Contradiction:

Improvetransmission reliabilityVSAvoidinterference level

Core Design Contradiction:

ReliabilityVSObject-generated harmful factors

Solution Approach 1:

Frequency channels with lower RoT thresholds act as intermediaries for M2M devices with large path loss. These devices transmit at lower power levels on these specific channels, avoiding the generation of excessive interference that would occur with high power transmissions on other channels.

Inventive Principle:

Principle #24Intermediary (Mediator)

Data Source

PatentEP2941932B1Multiple access scheme for multi-channels of a network with a limited link budget

Publication Date: 2016.06.22 QUALCOMM INC

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Figure 3A~3B

AI summary

Methods, systems, and devices are described for managing wireless communications in a machine-to-machine (M2M) wireless Wide Area Network (WAN). An operating frequency band of the M2M wireless WAN is divided into at least a first frequency channel and a second frequency channel. The first and second frequency channels being used for communications on a reverse link. A first rise over thermal (RoT) threshold is set for the first frequency channel. A second RoT threshold is set for the second frequency channel. The second RoT threshold is lower than the first RoT threshold.