Patent ID: 11888491
Assignee: TELEFONAKTIEBOLAGET LM ERICSSON (PUBL)
Field: Basic communication processes (Electrical engineering)
Classification: CPC H | IPC H

Claim 3:
4. A frequency detector for measuring and tuning a frequency of a controlled oscillator comprising:
a pulse generator for generating sampling pulses;
a multi-stage frequency divider connected to the output of the controlled oscillator;
a sample circuitry for sampling output states from each stage of the divider; and
a digital processing unit; wherein the sample circuitry is configured to sub-sample the output states of the divider at a sampling frequency lower than the frequency of the controlled oscillator; and
the digital processing unit is configured to calculate a frequency offset of the controlled oscillator based on the sampled output states and generate a control signal based on the frequency offset to tune the frequency of the controlled oscillator.