Patent ID: 8259876

Claim:
A system for tuning a radio receiver, comprising: a radio receiver configured to provide a downconverted digital error signal; a digital synthesizer circuit configured to generate a first local oscillator control signal, the digital synthesizer circuit including a counter configured to receive a reference frequency and an output of a local oscillator, a digital accumulator configured to receive and accumulate the output of the counter, and a synthesizer scaling element configured to receive the accumulated output; a digital automatic frequency control (AFC) circuit configured to generate a second local oscillator control signal corresponding to a desired local oscillator frequency, the digital synthesizer circuit being enabled to generate the first local oscillator control signal when the digital AFC circuit is disabled, the digital AFC circuit being enabled to generate the second local oscillator control signal when the digital synthesizer circuit is disabled, the first local oscillator control signal corresponding to an estimate of the desired local oscillator frequency; and a combining element combining the first local oscillator control signal and the second local oscillator control signal to form a combined local oscillator control signal.