Table of Contents

Encoding and decoding of character sets in text messages

Encoding

When sending a text message, Mobile Gateway uses the following 7-bit encoding by default:

  • GSM 03.38 7-bit default alphabet encoding

  • GSM 03.38 7-bit extended character set (€[]*^{}|~)

UCS-2 16-bit encoding

The moment Mobile Gateway finds a character that is not present in the GSM 7-bit table (e.g. the lowercase c with cedilla “ç”), it re-encodes the entire message using the UCS-2 16-bit encoding (which represents most Latin and Eastern characters). In that case, the maximum message length is reduced from 160 code units to 70 code units.

Decoding

When receiving a text message, Mobile Gateway uses the following decodings:

  • GSM 03.38 7-bit default alphabet with extended character set

  • GSM 03.38 8-bit data decoding using the default alphabet

  • UCS-2 16-bit decoding

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