Apparatus and method for automatically controlling a reference frequency in a dual mode receiver
US5493714A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 29, 1995 |
| Grant date | Feb 20, 1996 |
| Priority date | — |
| Expiry date | Jun 29, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B1/26
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
An apparatus and method for automatically controlling a reference frequency (120) in a receiver (104) that receives either analog (116) or digital (136) information signals. The receiver (18) includes a frequency translator (109) for translating a carrier frequency (137) to an intermediate frequency (118) and maintaining the intermediate frequency (118) at a desired value responsive to the reference frequency (120). A first measure of frequency error (211, 212) is detected between the reference frequency (120) and the intermediate frequency (118). A second measure of frequency error (125, 126) is detected between the reference frequency (120) and the intermediate frequency (118). A current signal (213) is produced responsive to the first measure of frequency error (211, 212) when the receiver receives the analog information signal (116) and responsive to the second measure of frequency error (125, 126) when receiver receives the digital information signal (136). A frequency control signal (130) is produced responsive to the current signal (213) to automatically control thereby the reference frequency (120) when the receiver (18) receives either analog (116) or digital (136) informa…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.