Patent · US Expired

Radar detection and dynamic frequency selection for wireless local area networks

US6697013B2 · kind B2 · utility

104Cited by
9References
19Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 31, 2001
Grant dateFeb 24, 2004
Priority date
Expiry dateApr 2, 2022

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04W84/12
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

A system for detecting and avoiding interference with radar signals in wireless network devices is described. The receiver circuit of the device receives incoming 5 GHz traffic. Such traffic could comprise both WLAN traffic as well as radar signals from radar systems. The incoming packets are treated as an input event, and are screened to be examined as radar pulses. Radar pulses are identified using the length of the detected event. The radar pulses are examined using frequency domain analysis, and the packet train is examined to find gaps between radar pulses. The periodic nature of the packet is determined using frequency domain and time domain analysis to calculate the period of the pulse train. Particular intervals within the pulse train are analyzed using threshold numbers of periodic pulses within the interval and threshold power levels for the pulses. The calculated period information is used to identify the radar source and screen non-radar traffic.

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