FM radio frequency plan using programmable output counter

US8254849B2 · kind B2 · utility

Assignee

• QUALCOMM Incorporated · US

Inventors

• Tzu-wang Pan · Irvine, US
• Yi Zeng · San Jose, US
• I-Hsiang Lin · Mountain View, US
• Pushp Trikha · San Diego, US
• Jeremy Darren Dunworth · San Diego, US
• Rahul Apte · San Francisco, US

Key dates

• Filing date: Apr 2, 2009
• Grant date: Aug 28, 2012
• Expiry date: Sep 29, 2030

Classification

• Technology area (CPC H): Electricity
• CPC primary: H04B15/06
• WIPO field: Telecommunications
• WIPO sector: Electrical engineering

Abstract

An FM radio with a wide frequency range operates in a cell phone without interfering with the VCO of the RF transceiver. The FM transceiver generates a VCO signal whose frequency varies by less than ±7% from the midpoint of a narrow first range. A synthesizer signal is generated by dividing the VCO frequency by a first divisor such that the synthesizer frequency varies over a lower frequency second range. The VCO frequency is also divided by a second divisor such that the synthesizer frequency varies over a third range. The upper limit of the second range falls at the lower limit of the third range. The lower limit of the second range is 85.5 MHz and the upper limit of the third range is 108.0 MHz. By also using a third divisor, a synthesizer signal with a range of 76-108 MHz is generated from the narrow first frequency range.