GSM cellular telephone and GPS receiver combination
US6122506A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 4, 1998 |
| Grant date | Sep 19, 2000 |
| Priority date | — |
| Expiry date | May 4, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03L7/1974
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A GPS/GSM receiver combination for receiving GSM and GPS signals using an RF GPS integrated circuit for downconverting the GPS signal. The GPS integrated circuit includes a synthesizer for generating LO signals, first and second downconverters for using the LO signals for downconverting the GPS signal, and a sampler for providing in-phase and quadrature phase sampled output signals representative of the GPS signal. The synthesizer includes a multi-mode divider for providing substantially the same first LO frequency at about the midpoint of the L1 and L2 GPS frequencies when either of a standard GSM reference frequency or historically common GPS reference frequency is selected. A standby mode in the integrated circuit is controlled by a power logic circuit using a power supply input as a logic control signal. The GSM/GPS receiver combination includes a GSM reference oscillator and a microprocessor system including a GSM frequency correction code for correcting the GSM reference frequency based upon a frequency correction beacon (FCB) signal received in the GSM signal. The GSM-based correction is then used for correcting the GSM reference frequency in order to center a frequency sear…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.