Abstract: A method and apparatus are provided which detects distortion in a received FM signal caused by amplitude modulating and phase transition of two combined FM signals. A method corrects and modifies the distortion by detecting a distorted sample, replacing the distorted sample with an appropriate sample, and applying a smoothing process to the sample.

Abstract: A radio device requires a tunable transceiver such that the transceiver can be accurately set to a desired frequency. When a signal with known frequency accuracy is being received, an offset detector can determine the frequency offset generated by the transceiver due to improper tuning. An automatic frequency control (AFC) system (100) is comprised of a tunable transceiver, an adaptive detector (102) for comparing an incoming sample from the tunable transceiver to an adaptive maximum deviation threshold for determining if a sample from the tunable transceiver should be used for the direct current (DC) component of the AFC, an offset detector (103) and an AFC control processor (105) for utilizing information from the offset detector to reduce the inaccuracy in frequency by tuning the transceiver towards the received signal frequency. The AFC control processor (105) utilizes one of more threshold levels for defining a maximum correction threshold (311) based upon the desired maximum offset correction.

Abstract: A radio device requires a tunable transceiver such that the transceiver can be accurately set to a desired frequency. When a signal with known frequency accuracy is being received, an offset detector can determine the frequency offset generated by the transceiver due to improper tuning. An automatic frequency control (AFC) system (100) is comprised of a tunable transceiver, an adaptive detector (102) for comparing an incoming sample from the tunable transceiver to an adaptive maximum deviation threshold for determining if a sample from the tunable transceiver should be used for the direct current (DC) component of the AFC, an offset detector (103) and an AFC control processor (105) for utilizing information from the offset detector to reduce the inaccuracy in frequency by tuning the transceiver towards the received signal frequency. The AFC control processor (105) utilizes one of more threshold levels for defining a maximum correction threshold (311) based upon the desired maximum offset correction.

Abstract: A method and apparatus are provided which detect distortion in a received FM signal caused by amplitude modulating and phase transition of two combined FM signals. The method (90) corrects and modifies the distortion by detecting a distorted sample (112), replacing the distorted sample with an appropriate sample (118), and applying a smoothing process (114) to the sample.