ECU Data Transmission Using Hybrid 16-Bit and 8-Bit Huffman Coding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing data transmission methods for electronic control units, such as those in motor vehicles, face inefficiencies due to large coding trees required for Huffman 16-bit coding, which are too large to fit in main memory and slow down data transmission, while Huffman 8-bit coding is less efficient and requires smaller trees.
Innovation Solution
Combining N-bit and M-bit Huffman coding, where N is an integral multiple of M, with separate coding trees for 16-bit and 8-bit data words, and using a single bit to decide which tree to use for decoding, allowing for manageable tree sizes and efficient data transmission.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If Huffman 16-bit coding is used to compress data efficiently, then data transmission efficiency is improved, but the coding tree size becomes too large to fit in main memory and slows down transmission
Solution Approach 1:
The patent divides the coding process into two segments: Huffman 16-bit coding for frequently occurring data patterns and Huffman 8-bit coding for less frequent patterns. This segmentation allows the system to use the more efficient 16-bit coding where it benefits most while falling back to the smaller 8-bit coding when needed, thus maintaining high overall compression efficiency without requiring a complete large 16-bit coding tree to be stored in memory.
2Volume of stationary object
If Huffman 8-bit coding is used to reduce coding tree size, then memory usage is improved, but data transmission efficiency decreases
Solution Approach 1:
The patent merges two different Huffman coding approaches (8-bit and 16-bit) into a single hybrid system. The 16-bit coding tree handles the most frequent data patterns with high efficiency, while the 8-bit coding tree handles the remaining patterns. This combination allows the system to achieve compression ratios close to pure 16-bit coding while keeping the memory footprint similar to 8-bit coding, thus resolving the trade-off between efficiency and memory usage.
3Adaptability or versatility
If a large coding tree is transmitted for decoding, then decoding capability is improved, but transmission time increases and main memory loading increases
Solution Approach 1:
The patent segments the decoding capability into two parts: a compact 8-bit decoding tree that can handle all possible 8-bit patterns, and a selective 16-bit decoding tree that handles only the most frequent patterns. This segmentation allows the system to transmit both trees efficiently and use them in combination, achieving full decoding capability without transmitting a single large comprehensive tree, thus reducing transmission time and memory loading.
Data Source
AI summary
A method for data transmission from a programming device to a control unit, the data being compressed by Huffman coding and transmitted with a Huffman coding tree for decoding from the programming device to the control unit, are decompressed and stored in the control unit, by performing, for a predetermined number of data words of N-bits, a first Huffman coding with a first coding tree; performing, for the remaining data words consisting of M-bits, a second Huffman coding with a second coding tree, N greater than M, the predetermined number of data words of N-bits and the remaining data words of M-bits consisting of more than two data words, generating coding trees for the N-bit and the M-bit data words, and transmitting them to the control unit, and providing all coded N-bit data words and N/M of successive M-bit data words with a preceding code bit.