Patent · US Expired

Intrusion detection radar system

US6677887B2 · kind B2 · utility

21Cited by
6References
15Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 4, 2001
Grant dateJan 13, 2004
Priority date
Expiry dateOct 4, 2021

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01S13/582
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

An outdoor microwave transceiver intrusion detector that alternately transmits pulses of RF energy at two different frequencies and uses range and direction of travel information derived from the phase of the two Doppler responses to optimize the signal processing and apply range dependent thresholds. The time delay between the onset of the transmitted pulse and the sample of the Doppler response is controlled to provide an accurate range cutoff. The two frequencies are selected so that the difference in phase of the Doppler response at the two frequencies increases from zero to ninety degrees as the target goes from the Transceiver to the maximum range. Digital signal processing is used to measure the difference in phase of the two Doppler responses and translate this information into location of the target. The location information is used to create a number of range bins. The response integration time and the threshold level are optimized for each of the range bins thereby minimizing the number of nuisance alarms.

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