Arrangement having tracking IF filter

US5159709A · kind A · utility

Assignee

• H.u.C. Elektronik GmbH · DE

Inventor

• Jens Hansen

Key dates

• Filing date: Oct 16, 1989
• Grant date: Oct 27, 1992
• Expiry date: Oct 16, 2009

Classification

• Technology area (CPC H): Electricity
• CPC primary: H03D3/005
• WIPO field: Basic communication processes
• WIPO sector: Electrical engineering

Abstract

In an FM receiver where the center frequency of an IF filter is varied depending on the received signal, an arrangement is described in which the passband of the retuned IF filter is selected so that a distinct resonance region having a relatively steep-edged drop of at least 6 dB exists in the middle of the channel; a less steep or level curve exists in a region essentially symmetrically spaced from the middle of the channel on both sides of the resonance region; and the pass limits lie essentially in symmetry with the middle of the channel.