Waveform collection for use in wireless telephone identification
US5999806A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 28, 1997 |
| Grant date | Dec 7, 1999 |
| Priority date | — |
| Expiry date | Feb 28, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04W12/79
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A system and method for collecting reference waveforms from authorized wireless telephones in a wireless telephone network. The collected reference waveforms are used by a fingerprint analyzer to distinguish telephone calls made by the authorized wireless telephone from telephone calls made by an unauthorized wireless telephone. The system maintains a pool of specially designated unassigned telephone numbers and selects one telephone number from the pool at random which is provided to a valid subscriber of an authorized wireless telephone. The randomly selected telephone number is to be called by the valid subscriber using the authorized cellular telephone for the purpose of collecting reference waveforms by the system. A radio frequency (RF) receiver of the system monitors and receives transmission signals from a plurality of wireless telephones. Each transmission signal contains a destination telephone number and an identification of its wireless telephone such as MIN/ESN identifiers. The system selects for purposes of collecting reference waveforms the transmission signal whose destination and wireless telephone identification respectively correspond to the randomly selected des…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.