Technology trends
Patent search
Sign In
Sign Up
Patent classifications
H
ELECTRICITY
Load children
H04
ELECTRIC COMMUNICATION TECHNIQUE
Load children
H04M
TELEPHONIC COMMUNICATION
Load children
3/00
Automatic or semi-automatic exchanges
Load children
Filter patents
View analytics
View as hierarchy
H04M3/42
Systems providing special services or facilities to subscribers
Load children
Filter patents
View analytics
View as hierarchy
H04M3/42229
Personal communication services, i.e. services related to one subscriber independent of his terminal and/or location
Load children
Filter patents
View analytics
View as hierarchy
H04M3/42263
where the same subscriber uses different terminals, i.e. nomadism
Load children
Filter patents
View analytics
View as hierarchy