CAN Node Bit Error Rate Estimation via Signaling Messages

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing CAN communication systems lack accurate adaptive communication control based on the current bit error rate of the channel, requiring static planning with estimated bit error rates.

Innovation Solution

A method to estimate the current bit error rate of a communication channel by evaluating signaling messages without extending existing protocols, using statistics from observed reactions to determine the bit error rate, which can be adapted dynamically based on channel conditions, allowing for efficient communication behavior adjustments.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If conventional CAN protocols are used with static bit error rate estimation, then system compatibility is maintained, but adaptive communication control accuracy deteriorates

Engineering Contradiction:
Improveadaptive communication controlVSAvoidbit error rate measurement accuracy
Core Design Contradiction:
Adaptability or versatilityVSMeasurement precision

Solution Approach 1:

The patent implements feedback by continuously monitoring signaling messages (error frames) on the communication channel and using this information to dynamically adjust communication parameters. Nodes count error frames and compare them against thresholds to adaptively control retransmission behavior and communication timing, transforming static protocols into adaptive systems that respond to real-time channel conditions

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The system uses existing error frame signaling messages, which are already part of the CAN protocol specification, to derive bit error rate information. Instead of requiring external measurement equipment or additional infrastructure, the communication nodes themselves generate and process the measurement data using the error frames that are naturally produced during normal operation, making the system self-measuring and self-adapting

Inventive Principle:
Principle #25Self-service

2Measurement precision

If additional measurement messages are transmitted to determine bit error rate, then measurement precision improves, but channel occupancy and system complexity increase

Engineering Contradiction:
Improvebit error rate measurement precisionVSAvoidprotocol extension complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The system repurposes existing error frame signaling messages that are already transmitted during normal CAN operation for the dual purpose of error indication and bit error rate measurement. Nodes simply count these existing error frames to derive BER statistics, eliminating the need for separate measurement messages or additional protocol complexity

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The error frame signaling messages serve multiple functions simultaneously: they indicate transmission errors to other nodes, trigger retransmission protocols, and provide measurement data for bit error rate estimation. This multi-functionality allows the system to achieve precise BER measurement without adding dedicated measurement infrastructure

Inventive Principle:
Principle #6Universality (Multi-functionality)

3Adaptability or versatility

If error frames are counted continuously to determine instantaneous bit error rate, then adaptability improves, but processing complexity and channel occupancy increase

Engineering Contradiction:
Improvedynamic communication adaptationVSAvoidcommunication throughput
Core Design Contradiction:
Adaptability or versatilityVSProductivity

Solution Approach 1:

The system implements periodic sampling of error frame rates at defined measurement intervals rather than continuous processing. Nodes count error frames occurring within specific time windows and use these periodic measurements to adjust communication parameters, balancing adaptability with processing efficiency and maintaining high channel utilization

Inventive Principle:
Principle #19Periodic action

Solution Approach 2:

The system monitors error frames with selective attention, focusing processing resources on analyzing error frame rates when they exceed certain thresholds or occur during critical communication periods. Not every error frame triggers full processing, allowing the system to maintain adaptability while avoiding excessive processing overhead that would reduce overall communication productivity

Inventive Principle:
Principle #16Partial or excessive action

Data Source

PatentEP2338248B1Method for operating a communication system with a plurality of nodes and communication system therefor
Publication Date: 2020.05.06 ROBERT BOSCH GMBH
  • EP2338248B1 patent drawingFigure 1~3
  • EP2338248B1 patent drawingFigure 4~5
  • EP2338248B1 patent drawing

AI summary

The invention relates to a method (41) for operating a communication system (11) with a plurality of nodes (13) that have access to a common channel (15) of the communication system (11). In the method (41), a transmission process (31) for transmitting a message (33) via the channel (15) is monitored for bit errors (35). When a bit error (35) occurs, a signaling message (37) is transmitted via the channel (15) for signaling the bit error (35). In order to provide a method (41) for operating such a communication system (11) that enables a control of communication processes between the nodes (13) as a function of a bit error rate (BER) of the channel, a signaling rate (r) of the signaling messages (37) is measured and a bit error rate (BER) of the channel (15) is determined as a function of the signaling rate (r).