Train Communication System Digital Data Transmission

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional train communication systems face challenges in reliably transmitting high-quality moving image and audio information due to signal degradation and electromagnetic noise, requiring wide communication frequency bands and being prone to disruptions from disconnection or device failures.

Innovation Solution

A communication system that separates image and control data transmission, converting all information into digital data and using digital data communication devices to store and display images, allowing for reliable display even if the image data communication device fails, by utilizing Ethernet interfaces and error correction technologies.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If analog data signals are used to transmit moving image information, then the communication frequency band required is wide, but signal degradation occurs and electromagnetic noise is superimposed

Engineering Contradiction:

Improveimage transmission reliabilityVSAvoidsignal degradation and electromagnetic noise

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent replaces the analog transmission system with a digital transmission system. Specifically, it substitutes the analog data signal transmission path with a digital data transmission path that uses packet communication protocols, thereby eliminating the harmful effects of signal degradation and electromagnetic noise that plague analog systems.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent changes the fundamental parameter of signal representation from analog continuous waves to digital discrete packets. By converting image information into digital data packets with error correction codes and using packet-based transmission, the system achieves immunity to signal degradation and electromagnetic interference.

Inventive Principle:

Principle #35Parameter changes

2Adaptability or versatility

If multi-channel communication is used to multiplex multiple moving image or audio lines, then further wider frequency band is required, but the frequency band is difficult to realize

Engineering Contradiction:

Improvemulti-channel communication capabilityVSAvoidfrequency band width

Core Design Contradiction:

Adaptability or versatilityVSArea of stationary object

Solution Approach 1:

The patent segments the transmission system into multiple independent digital data transmission paths, each capable of carrying multiple multiplexed channels. By dividing the communication into packet-based data streams with separate error correction for each channel, multiple image and audio lines can be transmitted simultaneously without requiring excessively wide frequency bands.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent creates a universal digital transmission infrastructure that can handle multiple types of data (image, audio, control) through a single packet-based communication protocol. This multi-functional system allows flexible channel allocation and multiplexing without requiring separate dedicated frequency bands for each channel type.

Inventive Principle:

Principle #6Universality (Multi-functionality)

3Reliability

If transmission line disconnection or communication device failure occurs, then transmission of image information is prevented, but the information cannot be displayed

Engineering Contradiction:

Improvedisplay function reliabilityVSAvoidtransmission path vulnerability

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent implements error correction coding and redundancy mechanisms in advance of potential failures. By incorporating forward error correction codes in the digital packet structure and designing the system to tolerate packet loss, the transmission path becomes resilient to disconnections and device failures, ensuring continuous display functionality.

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

Solution Approach 2:

The patent employs acknowledgment and retransmission protocols where the receiving end sends feedback signals to confirm successful packet reception. If packets are lost or corrupted during transmission, the feedback mechanism triggers automatic retransmission, ensuring reliable delivery of image information even in the presence of transmission line issues or device failures.

Inventive Principle:

Principle #23Feedback

Data Source

PatentUS8766877B2Communication system in trains

Publication Date: 2014.07.01 HITACHI LTD

AI summary

A communication system in trains comprises a control data communication device 400 and an image data communication device 300 installed in each of the cars. The control data communication device 400 transmits train operation information, train location information, control instructions of train-mounted apparatuses, and the like. The image data communication device 300 transmits image information such as moving images and still images, audio information such as in-train announcement, textual information for caption display, and operation log information of apparatuses, which form the contents, to a display unit 200 installed in each of the cars and to apparatuses 500 such as a telephone. The display unit 200 switches the display on the screen in accordance with train control information transmitted from the control data communication device 400 through the image data communication device 300.