Database Compression for Intelligent On-board Vehicle Controllers

The vehicle fleet of public transportation companies is often equipped with intelligent on-board passenger information systems. A frequently used but time and labor-intensive way for keeping the on-board controllers up-to-date is the manual update using different memory cards (e.g. flash cards) or portable computers. This paper describes a compression algorithm that enables data transmission using low bandwidth wireless radio networks (e.g. GPRS) by minimizing the amount of data traffic. In typical cases it reaches a compression rate of an order of magnitude better than that of the general purpose compressors. Compressed data can be easily expanded by the low-performance controllers, too.

• Ágoston Winkler
• Sándor Juhász
• Zoltán Benedek

• Data analysis
• data compression
• differentialencoding
• run-length encoding
• vehicle control.

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