Soft Handover for VoIP Services via Dual RAN Connections

Solution Overview

Problem

Client devices experience interruptions in call services when disconnecting from one radio access network and reconnecting to another due to signal quality thresholds, leading to dropped calls or lost packets, and increased network traffic for retransmissions.

Innovation Solution

Establishing a secondary network connection before the signal quality of the primary connection meets a threshold, allowing seamless transfer without interruptions and reducing the need for retransmissions by pre-establishing a stable bearer for packet routing.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the client device disconnects from the primary radio access network when signal quality fails to satisfy a threshold, then the device can reconnect to another network, but call interruptions and packet losses occur during the transition

Engineering Contradiction:

Improvecall service continuityVSAvoidcall interruption duration

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The patent applies preliminary action by establishing a secondary network connection before the primary connection's signal quality degrades below the threshold. The device proactively monitors signal quality and initiates connection to a secondary radio access network while the primary connection is still adequate, allowing seamless handover without call interruptions when the primary connection fails.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent implements beforehand cushioning by creating a backup network connection in advance. This secondary connection acts as a cushion or safety net that is already established and ready to take over immediately when the primary connection fails, preventing call drops and packet losses during the transition.

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

2Loss of energy

If the client device waits until signal quality threshold is met before switching networks, then network resources are conserved, but dropped calls and packet losses increase

Engineering Contradiction:

Improvenetwork traffic for retransmissionsVSAvoidcall service continuity

Core Design Contradiction:

Loss of energyVSReliability

Solution Approach 1:

The patent applies preliminary action by establishing a secondary network connection before the primary connection's signal quality degrades below the threshold. The device proactively monitors signal quality and initiates connection to a secondary radio access network while the primary connection is still adequate, allowing seamless handover without call interruptions when the primary connection fails.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent implements feedback by continuously monitoring the signal quality of the primary radio access network connection. Based on this feedback, the device intelligently determines when to establish a secondary connection and when to switch between networks, optimizing both network resource usage and call service continuity.

Inventive Principle:

Principle #23Feedback

3Reliability

If the client device establishes a secondary network connection before threshold failure, then call continuity is maintained, but network resources and energy consumption increase

Engineering Contradiction:

Improvecall service continuityVSAvoidenergy for maintaining multiple connections

Core Design Contradiction:

ReliabilityVSUse of energy by moving object

Solution Approach 1:

The patent applies preliminary action by establishing a secondary network connection before the primary connection's signal quality degrades below the threshold. The device proactively monitors signal quality and initiates connection to a secondary radio access network while the primary connection is still adequate, allowing seamless handover without call interruptions when the primary connection fails.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent implements dynamics by making the network connection configuration adaptive rather than static. The device dynamically adjusts the number of active network connections based on real-time signal quality conditions, maintaining one connection when adequate and establishing a second connection only when needed, thus optimizing energy consumption while ensuring service continuity.

Inventive Principle:

Principle #15Dynamics

Data Source

PatentUS9883435B2Soft handover for a voice over internet protocol service

Publication Date: 2018.01.30 VERIZON PATENT & LICENSING INC

AI summary

A device may establish a first connection to a first radio access network (RAN) associated with a first radio access technology (RAT). The device may register to receive a call service via the first RAN. The device may receive the call service via the first connection. The device may establish a second connection to a second RAN associated with a second RAT that is different from the first RAT. The device may register to receive the call service via the second RAN. The device may compare a first signal quality metric, associated with the first connection, and a second signal quality metric associated with the second connection. The device may cause the call service to be transferred from the first connection to the second connection, based on comparing the first signal quality metric and the second signal quality metric, without causing an interruption to the call service.