Karl Hellwig
45Patents
12h-index
56Co-inventors
84Inventor score
Filing activity: Aug 20, 1984 → Jul 24, 2018
Most-cited inventions
| Patent | Title | Area | Cited by | Status |
|---|---|---|---|---|
| US5490136A | Method of controlling transmission on a same radio channel of variable-rate information streams in radio communication systems | Electricity | 116 | Expired |
| US6345251B1 | Low-rate speech coder for non-speech data transmission | Physics | 81 | Expired |
| US8634838B2 | Connection set-up between two terminals | Electricity | 70 | Active |
| US6856612B1 | Methods and systems for call routing and codec negotiation in hybrid voice/data/internet/wireless systems | Electricity | 55 | Expired |
| US6611804B1 | Universal TTY/TDD devices for robust text and data transmission via PSTN and cellular phone networks | Physics | 49 | Expired |
| US6295302A | Alternating speech and data transmission in digital communications systems | Electricity | 49 | Expired |
| US5982766A | Power control method and system in a TDMA radio communication system | Electricity | 34 | Expired |
| US6658381B1 | Methods and systems for robust frame type detection in systems employing variable bit rates | Emerging Cross-Sectional Technologies | 22 | Expired |
| US7500018B2 | Efficient in-band signaling for discontinuous transmission and configuration changes in adaptive multi-rate communications systems | Electricity | 19 | Active |
| US5687184A | Method and circuit arrangement for speech signal transmission | Electricity | 19 | Expired |
| US4889756A | Sheet-like, multilayer, laser-optical recording material | Emerging Cross-Sectional Technologies | 18 | Expired |
| US6163577A | Source/channel encoding mode control method and apparatus | Electricity | 13 | Expired |
| US5799201A | Signal processor | Electricity | 11 | Expired |
| US6826404B2 | Tone signalling with TFO communication links | Electricity | 10 | Expired |
| US8374587B2 | Method for codec negotiation and selection | Electricity | 8 | Active |
| US5602766A | Method of and device for forming the sum of a chain of products | Physics | 6 | Expired |
| US4607362A | Method of and circuit arrangement for establishing conference connections in a switching system | Electricity | 6 | Expired |
| US5657421A | Speech signal transmitter wherein coding is maintained during speech pauses despite substantial shut down of the transmitter | Physics | 5 | Expired |
| US8595018B2 | Technique for controlling codec selection along a complex call path | Electricity | 5 | Active |
| US9204276B2 | Relaying a private emergency point to a public emergency point | Electricity | 4 | Active |
| US7620052B2 | Method and node for selecting a codec type or configuration by extending the list comprising codecs for transcoder/tandem free operation by further codecs supported by the node | Electricity | 4 | Expired |
| US6466789B1 | Method and device for avoiding interruptions in voice transmissions | Electricity | 4 | Expired |
| US7328038B2 | Power control in mobile communication systems | Electricity | 3 | Expired |
| US8817617B2 | Individual codec pathway impairment indicator for use in a communication | Electricity | 3 | Active |
| US8351973B2 | Short message service (SMS) over service access point identifier 0 (SAPI-0) | Electricity | 2 | Active |
Source: USPTO / EPO open patent data. Inventor disambiguation is heuristic; counts are objective bibliographic measures.