IPC Subgroup
H04L 27/3 wherein each code element is represented by a combination of frequencies
Introduced: September 1968
Last revised: January 2006
Full Title
Modulated-carrier systems > Systems using multi-frequency codes > wherein each code element is represented by a combination of frequencies
Classification Context
- Section:
- ELECTRICITY
- Class:
- ELECTRIC COMMUNICATION TECHNIQUE
- Subclass:
- TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION