TIDUF89 September   2024

 

  1.   1
  2.   Description
  3.   Resources
  4.   Features
  5.   Applications
  6.   6
  7. 1System Description
    1. 1.1 Detection Theory
    2. 1.2 Multi-Pass Architecture
  8. 2System Overview
    1. 2.1 System Design Theory
      1. 2.1.1 Long Detection Range
        1. 2.1.1.1 Antenna Design for Long Detection Range
        2. 2.1.1.2 SNR Compensation for Long Detection Range
        3. 2.1.1.3 Smart Detection Logic
      2. 2.1.2 Low Power Consumption
        1. 2.1.2.1 Efficient Chirp Design
        2. 2.1.2.2 Deep Sleep Power Modes
        3. 2.1.2.3 Hardware Accelerator
      3. 2.1.3 Low False Alarm Rate
        1. 2.1.3.1 Typical Causes of False Alarms
        2. 2.1.3.2 False Alarms Outside the Detection Zone
        3. 2.1.3.3 False Alarms Within the Detection Zone
        4. 2.1.3.4 Adaptive State Machine
  9. 3Hardware, Software, Testing Requirements, and Test Results
    1. 3.1 Hardware Requirements
    2. 3.2 Software Requirements
    3. 3.3 Test Setup
      1. 3.3.1 Test 1 - Detection Range
      2. 3.3.2 Test 2 - False Alarm Rate
      3. 3.3.3 Test 3 - Power Consumption
    4. 3.4 Test Results
  10. 4Design Files
    1. 4.1 Schematics
    2. 4.2 Bill of Materials
  11. 5Tools and Software
  12. 6Document Support
  13. 7Support Resources
  14. 8Trademarks
  15. 9About the Authors

2.1.3.1 Typical Causes of False Alarms

Rejecting false alarms is one of the principle benefits of using radar in surveillance systems. The most common causes of false alarms in residential environments include the following:

  • Cars driving on the street
  • Trees and bushes blowing in the wind
  • Neighbors walking on the sidewalk
  • Heaters or condensers nearby causing differences in temperature
  • Small animals in the field of view
  • Bug nests very nearby the radar

Typically in these systems, users are able to select a detection zone, where the user wants to detect movement, and exclusion zones, where the user does not want to detect movement. Therefore, this list of false alarms can be divided into two categories: false alarms from movement within the expected detection zone, and false alarms from movement outside the expected detection zone

Table 2-4 Sources of False Alarms
False Alarms Within the Detection ZoneFalse Alarms Outside the Detection Zone
  • Trees and bushes blowing in the wind
  • Heaters or condensers nearby causing differences in temperature
  • Small animals in the field of view
  • Bug nests very nearby the radar
  • Cars driving on the street
  • Neighbors walking on the sidewalk