Back to results
US 5,630,215 AGranted
Radio having a combined PLL and AFC loop and method of operating same
AssigneeMotorola, Inc.
InventorsWilliam T. Waldie, Joseph P. Heck
Life of this patent
Estimating the term…
Abstract
A radio (100) has a combined phase locked loop (PLL) (207) and an automatic frequency control (AFC) loop (215, 109, 111) and a method of operating the same. A mixer (201) converts the received RF signal (117) to an intermediate frequency (IF) signal (219) responsive to an injection signal (217). The PLL (207) locks the injection signal (217) to the received RF signal (117) responsive to a difference between the IF signal (219) and a reference signal (119). The AFC loop (215, 109, 111) locks the reference signal (119) to the received RF signal (117) responsive to a difference between the injection signal (217) and the reference signal (119).
Claims31
A radio comprising:
- means for converting a received radio frequency (RF) signal of interest, if any, to an intermediate frequency (IF) signal responsive to an injection signal;
- first means for locking the injection signal to the received RF signal responsive to a difference between the IF signal and a reference signal to precisely locate the received RF signal;
- and
- second means for locking the reference signal to the received RF signal responsive to a difference between the injection signal and the reference signal to generally locate the received RF signal,
- wherein the first means for locking and the second means for locking operate simultaneously.
2 more elements
An intermediate frequency stage of a radio frequency receiver comprising:
- means for converting a received radio frequency (RF) signal of interest, if any, to an intermediate frequency (IF) signal responsive to an injection signal;
- first means for filtering the IF signal to produce a filtered IF signal;
- means for limiting the filtered IF signal to produce a limited IF signal;
- phase detecting means for comparing the limited IF signal and a reference signal to produce a phase error signal;
- second means for filtering the phase error signal to produce a filtered phase error signal;
- means for generating the injection signal responsive to the filtered phase error signal to precisely locate the received RF signal;
- frequency detecting means for comparing the injection signal and the reference signal to produce a frequency error signal;
- and
- reference signal source means for generating the reference signal responsive to the frequency error signal to generally locate the received RF signal,
- wherein the phase detecting means, the second means for filtering, the means for generating the frequency detecting means and the reference signal source means operate simultaneously.
7 more elements
A radio comprising:
- reception means comprising:
- means for converting a received radio frequency (RF) signal of interest, if any, to an intermediate frequency (IF) signal responsive to an injection signal;
- first means for filtering the IF signal to produce a filtered IF signal;
- means for limiting the filtered IF signal to produce a limited IF signal;
- phase detecting means for comparing the limited IF signal and a reference signal to produce a phase error signal;
- second means for filtering the phase error signal to produce a filtered phase error signal;
- means for generating the injection signal responsive to the filtered phase error signal to precisely locate the received RF signal;
- frequency detecting means for comparing the injection signal and the reference signal to produce a frequency error signal;
- transmission means for transmitting an RF signal responsive to the reference signal;
- means for processing the frequency error signal to produce a control signal;
- and
- adaptive reference signal source means for providing the reference signal responsive to the control signal to generally locate the received RF signal,
- wherein the phase detecting means, the second means for filtering, the means for generating the frequency detecting means, the means for processing and the adaptive reference signal source means operate simultaneously.
10 more elements
A radio having a phase locked loop for producing an injection signal responsive to an IF signal and a reference signal, the radio comprising:
- phase detecting means for comparing the IF signal and the reference signal to produce a phase error signal;
- means for filtering the phase error signal to produce a filtered phase error signal;
- means for generating the injection signal responsive to the filtered phase error signal to precisely locate the received RF signal;
- frequency detecting means for comparing the injection signal and the reference signal to produce a frequency error signal;
- means for processing the frequency error signal to produce a control signal;
- and
- adaptive reference signal source means for providing the reference signal responsive to the control sign to generally locate the received RF signal;
- wherein the phase detecting means, the means for fitting, the means for generating the frequency detecting means, the means for processing and the adaptive reference signal source means operate simultaneously.
5 more elements
A method of operating a radio comprising the steps of:
- converting a received radio frequency (RF) signal of interest, if any, to an intermediate frequency (IF) signal responsive to an injection signal;
- locking the injection signal to the received RF signal responsive to a difference between the IF signal and a reference signal to precisely locate the received RF signal;
- and
- locking the reference signal to the received RF signal responsive to a difference between the injection signal and the reference signal to generally locate the received RF signal;
- wherein the step of locking the injection signal to the received RF signal and the step of locking the reference signal to the received RF signal operate simultaneously.
2 more elements
A method of operating an intermediate frequency stage of a radio frequency receiver comprising the steps of:
- converting a received radio frequency (RF) signal of interest, if any, to an intermediate frequency (IF) signal responsive to an injection signal;
- filtering the IF signal to produce a filtered IF signal;
- limiting the filtered IF signal to produce a limited IF signal;
- comparing the limited IF signal and a reference signal to produce a phase error signal;
- filtering the phase error signal to produce a filtered phase error signal;
- generating the injection signal responsive to the filtered phase error signal to precisely locate the received RF signal;
- comparing the injection signal and the reference signal to produce a frequency error signal;
- and
- generating the reference signal responsive to the frequency error signal to generally locate the received RF signal,
- wherein the steps of comparing the limited RF signal and a reference signal, filtering the phase error signal, generating the injection signal comparing the injection signal and the reference signal and generating the reference signal operate simultaneously.
7 more elements
A method of operating a radio comprising the steps of:
- receiving a radio frequency (RF) signal of interest, if any, the step of receiving further comprising the steps of:
- converting the received RF signal to an intermediate frequency (IF) signal responsive to an injection signal;
- filtering the IF signal to produce a filtered IF signal;
- limiting the filtered IF signal to produce a limited IF signal;
- comparing the limited IF signal and a reference signal to produce a phase error signal;
- filtering the phase error signal to produce a filtered phase error signal;
- generating the injection signal responsive to the filtered phase error signal to precisely locate the received RF signal;
- and
- comparing the injection signal and the reference signal to produce a frequency error signal;
- transmitting an RF signal responsive to the reference signal;
- processing the frequency error signal to produce a control signal;
- and
- adjusting the reference signal responsive to the control signal to generally locate the received RF signal,
- wherein the steps of comparing the limited IF signal and a reference signal, filtering the phase error signal, generating the injection signal, comparing the injection signal and the reference signal, processing the frequency error signal and adjusting the reference signal operate simultaneously.
11 more elements
A method of operating a radio having a phase locked loop for producing an injection signal responsive to an IF signal and a reference signal, the method comprising the steps of:
- comparing the IF signal and the reference signal to produce a phase error signal;
- filtering the phase error signal to produce a filtered phase error signal;
- generating the injection signal responsive to the filtered phase error signal to precisely locate the received RF signal;
- comparing the injection signal and the reference signal to produce a frequency error signal;
- processing the frequency error signal to produce a control signal;
- and
- adjusting the reference signal responsive to the control signal to generally locate the received RF signal,
- wherein the steps of comparing the IF signal and the reference signal, filtering the phase error signal, generating the injection signal, comparing the injection signal and the reference signal, processing the frequency error signal and adjusting the reference signal operate simultaneously.
5 more elements
A radiotelephone comprising:
- a mixer for converting a received radio frequency (RF) signal to an intermediate frequency (IF) signal responsive to an injection signal;
- a phase locked loop for locking the injection signal to the received RF signal responsive to a difference between the IF signal and a reference signal to precisely locate the received RF signal;
- and
- an automatic frequency controller for locking the reference signal to the received RF signal responsive to a difference between the injection signal and the reference signal to generally locate the received RF signal,
- wherein the phase locked loop and the automatic frequency controller operate simultaneously.
2 more elements
Dependencies are inferred from the claim text.