Patent · US Expired

Selectable doppler filter for radar systems

US4709236A · kind A · utility

17Cited by
8References
19Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMay 8, 1985
Grant dateNov 24, 1987
Priority date
Expiry dateMay 8, 2005

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01S13/53
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

An arrangement for selecting between different doppler filter pairs having response characteristics optimized for ground clutter or moving rain clutter rejection. The selecting process detects the amplitude and mean doppler of the received radar echoes. The filter which is optimized for rain clutter rejection is normally used until clutter amplitude is detected above a predetermined value and the mean doppler is detected as being equal to or near zero. When such a detection is made, the filter optimized for ground clutter rejection is selected. Portions of the selecting device allow for the selection to be determined over several samples rather than switching the filters in each sample or coherent processing interval. Another portion of the circuitry changes the predetermined values which must be exceeded for a selection of the ground clutter filter, thereby preventing another filter change with only a small change in detected amplitude or mean doppler.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.