Inventor
NIZAMUDDIN NADIR
CA4 patents
Patents
4 patentsUS5027345AJun 25, 1991
Digital key telephone system
NORTHERN TELECOM LTD27 citations89
US4893310AJan 9, 1990
Digital key telephone system
NORTHERN TELECOM LTD25 citations89
US5136585AAug 4, 1992
Digital key telephone system
NORTHERN TELECOM LTD43 citations88
US4626628ADec 2, 1986
Telephone line circuit having time-shared DTMF receivers
NORTHERN TELECOM LTD6 citations53