Intermediate frequency FM receiver using analog oversampling to increase signal bandwidth
US5483695A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 13, 1994 |
| Grant date | Jan 9, 1996 |
| Priority date | — |
| Expiry date | Apr 13, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B1/30
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
An FM receiver comprising a local oscillator (23), a heterodyning stage (24) and a demodulator stage (33). The heterodyning stage has a signal producing arrangement and a multiplier arrangement. The signal producing arrangement (25,26,27,29,30,31,32) produces n signals a.sub.1 . . . a.sub.n wherein each signal consists of a message signal modulated at the intermediate frequency of the receiver, and these signals a.sub.1 . . . a.sub.n are related by the expression EQU a.sub.i =cos [.omega..sub.IF t+k.sub.f .intg..sup.t A(t)*dt+.OMEGA.+.pi.*(.sup.i /n)] where .omega..sub.IF, k.sub.f and .OMEGA. are constants, n is a positive integer greater than or equal to 2 and i takes the values of all positive integers up to and including n. The multiplier arrangement (28) multiplies the n signals together and thus produces an output signal from the heterodyning stage, wherein the message signal is modulated at a frequency of n times the intermediate frequency.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.