Inventor
HIRZEL FREDERIC J
US11 patents
⚠️ This page may combine multiple inventors who share the name “HIRZEL FREDERIC J”. Patents are grouped by organization below to help distinguish them — per-person disambiguation is on the roadmap.
VOCAL TECHNOLOGIES LTD
9 patentsUS5086454AFeb 4, 1992
Direct connect modem deriving power from telephone line
VOCAL TECHNOLOGIES LTD91 citations94
US6327301B1Dec 4, 2001
Detection and adaptation to digital network impairments by PCM modems
VOCAL TECHNOLOGIES LTD11 citations72
US6480549B1Nov 12, 2002
Method for determining attenuation in a digital PCM channel
VOCAL TECHNOLOGIES LTD11 citations65
US6643270B1Nov 4, 2003
Method of compensating for systemic impairments in a telecommunications network
VOCAL TECHNOLOGIES LTD5 citations61
US6633604B1Oct 14, 2003
Method of improving echo canceller training in modems and of discovering characteristics of a PCM channel
VOCAL TECHNOLOGIES LTD2 citations61
US6222890B1Apr 24, 2001
Variable spectral shaping method for PCM modems
VOCAL TECHNOLOGIES LTD2 citations61
US6848073B2Jan 25, 2005
Trellis encoding technique for PCM modems
VOCAL TECHNOLOGIES LTD0 citations51
US6301683B1Oct 9, 2001
Trellis encoding technique for PCM modems
VOCAL TECHNOLOGIES LTD0 citations50
US6067034AMay 23, 2000
Maximal bit packing method
VOCAL TECHNOLOGIES LTD0 citations44