Dynamic Code Rate Adjustment for Synchronized Content Distribution

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing distribution systems face challenges in ensuring that reception devices can start content reproduction at the set reproduction start time due to varying communication speeds, leading to potential data insufficiency and extreme code rate fluctuations.

Innovation Solution

A distribution system that dynamically adjusts the code rate of content data based on the remaining time before reproduction start and available reproduction time, ensuring sufficient data storage and stable reproduction by changing the code rate to avoid meaningless reductions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the code rate is determined based on only the available reproduction time, then the code rate can be adjusted to ensure data sufficiency, but the code rate becomes extremely small immediately after reception starts and extremely high immediately before reproduction start time

Engineering Contradiction:
Improvedata sufficiencyVSAvoidcode rate stability
Core Design Contradiction:
ReliabilityVSAdaptability or versatility

Solution Approach 1:

The patent changes the parameter used for code rate determination from solely 'available reproduction time' to a combination of 'elapsed time since reception start' and 'available reproduction time'. This dual-parameter approach prevents extreme code rate fluctuations by considering the temporal progression of data accumulation alongside the current buffer status.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent implements dynamic code rate adjustment that adapts to the reception phase. During initial reception, the code rate is moderated to avoid excessive fluctuations, while later in the reception period, the code rate can be more aggressively adjusted to ensure data sufficiency. This time-varying strategy makes the system more adaptable to different reception stages.

Inventive Principle:
Principle #15Dynamics

2Speed

If the communication speed becomes extremely low, then data transmission may be delayed, but the data amount stored in the storage device may not reach a sufficient amount by the reproduction start time

Engineering Contradiction:
Improvecommunication speedVSAvoiddata availability
Core Design Contradiction:
SpeedVSReliability

Solution Approach 1:

The patent performs preliminary estimation of the required code rate based on the reproduction start time and current reception status. By calculating the necessary data accumulation rate in advance and adjusting the code rate proactively, the system ensures that sufficient data will be available by the reproduction start time, even when communication speed is low.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent implements a feedback mechanism where the code rate is continuously adjusted based on the current available reproduction time and elapsed reception time. This closed-loop control ensures that the data accumulation rate adapts to actual communication conditions, maintaining data availability despite variations in communication speed.

Inventive Principle:
Principle #23Feedback

3Stability of the object's composition

If multiple reception devices synchronize content reproduction, then synchronized playback is achieved, but code rate adjustments must account for multiple devices' data accumulation status

Engineering Contradiction:
ImprovesynchronizationVSAvoidcode rate control
Core Design Contradiction:
Stability of the object's compositionVSDevice complexity

Solution Approach 1:

The patent applies local quality by allowing each reception device to independently determine its own code rate based on its specific reception status and available reproduction time. Instead of imposing a uniform code rate on all devices, each device optimizes its data accumulation rate according to its local conditions, simplifying the overall control while maintaining synchronization.

Inventive Principle:
Principle #3Local quality

Data Source

PatentEP2498492B1Distribution system
Publication Date: 2018.08.22 NEC CORP
  • EP2498492B1 patent drawingFigure 1
  • EP2498492B1 patent drawingFigure 2
  • EP2498492B1 patent drawingFigure 3

AI summary

A distribution system 100 includes a transmission device 110 and a reception device 120. The transmission device transmits content data coded with a certain code rate to the reception device. The reception device, while receiving the content data transmitted by the transmission device, stores received data into a storage device and also reproduces content based on the stored data. The distribution system determines a code rate based on a remaining time before reproduction start time from a present moment and an available reproduction time, which is a time available for reproduction of the content based on the stored data. The transmission device changes the code rate of the content data to be transmitted to the determined code rate. The reception device starts reproduction of the content at the reproduction start point.