ADAPTIVE TRACKING NOTCH FILTER SYSTEM
Assignee
MASSACHUSETTS INSTITUTE OF TECHNOLOGY
Filed
Feb 23, 1990
Granted
Jul 19, 1994
Location
Cambridge MA (Draper Lab/MIT)
Abstract
An automatic tracking notch filter system tracks a large-magnitude narrow band signal through frequency effectively eliminating it. A frequency variable notch filter is responsive to a control input at which is applied a small amplitude AC dither signal. The resulting fluctuation in frequency of the notch filter causes corresponding fluctuations in the magnitude of the notch filter output. The output signal is rectified and band pass filtered around the dither frequency before being demodulated with the dither signal to provide a DC error signal indicating the magnitude and direction in frequency of the filter misalignment. The error signal is integrated and input to the control input of the notch filter with the dither signal such that the notch filter tracks the narrow band signal in response to the feedback signal provided at its control input.
Source: Google Patents
35 USC §181 Secrecy Order
Imposed
Sep 21, 1990
Rescinded
Feb 18, 1994
Duration
3 years, 5 months
Inventor
- 1NORVAL P. SMITH
Sensitive facility: Cambridge MA (Draper Lab/MIT)
Record Details
- Patent number
- US 5331299
- Application
- 00748393
- Aerospace match
- No
- Dataset source
- 35 USC §181 SO records