Active waveform collection for use in transmitter identification
US6035188A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 27, 1996 |
| Grant date | Mar 7, 2000 |
| Priority date | — |
| Expiry date | Jun 27, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04W74/06
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A method and system for actively and rapidly collecting reference waveforms from a large number of cellular telephones is provided. The reference waveforms are used to generate fingerprints which are used to distinguish between authorized cellular telephones and unauthorized cellular telephones. Initially, the system selects a cellular telephone whose reference waveform is desired. The selected cellular telephone is then sent a polling message such as a page or registration request. The cellular telephone receives the polling message and transmits a radio frequency (RF) signal containing a reference waveform that contains certain transmission characteristics unique to the selected cellular telephone. From the received RF signal, the reference waveform is extracted and stored. Preferably, the selected cellular telephone is polled repeatedly in order to receive a sufficiently large number of reference waveforms to be able to generate an accurate fingerprint. One method of polling the cellular telephone is by calling the selected cellular telephone through a cellular telephone system. Another method of polling the cellular telephone is by transmitting a control message such as a page,…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.