SAS2012 UWB Stepped-FM Sensor for Home Security Y. Ota, R. Nakamura, and A. Kajiwara Graduate School of Environmental Engineering, The University of Kitakyushu, Japan Kajiwara lab.
Overview Background Stepped-FM scheme Proposed intruder detection sensor Measurement results Conclusions Kajiwara lab. 2
Background People suffer from intruders Home security sensor has attracted considerable attention Many types of sensors Infra-red narrow coverage area Video susceptible to false alarms Doppler Kajiwara lab. 3
UWB (Ultra Wide-Band) Advantages High range-resolution Less penetration loss Power spectral emission less than -41.3dBm/MHz UWB is expected to be employed for any applications Disadvantages Interference to/from other wireless systems High speed A/D device required Stepped-FM scheme Kajiwara lab. 4
Stepped-FM scheme Advantages Low speed A/D device available Independent narrow band pulses High spectrum efficiency Co-existence with other wireless systems Other wireless systems Frequency UWB-Impulse Radio Frequency UWB Stepped-FM UWB Stepped-FM sensor Kajiwara lab. 5
Measurement setup Measurement parameters Center frequency Band-width 3.6GHz 0.2,0.5,1.0GHz Antenna Type Non-directional bi-conical Height 1.0m Measurement house Transmitted power Sampling rate -15dBm 100kS/sec Antennas located at a center of house Broad coverage area Kajiwara lab. 6
Sensitivity to location of intruder Bandwidth: 0.5GHz Balcony (outside) Living room Room B Tx&Rx Room A Room C Entrance Sensitivity to location of intruder (received power difference for various locations of human) Kajiwara lab. 7
Two alarm zones Radio leakage to outside area cause false alarm Different alarm level for two zones Zone-1 Interior living space (e.g. living room) Zone-2 Including outdoor The performance improved (e.g. capability balcony) Two alarm zones Kajiwara lab. 8
Measurement scenarios Moving trajectory of subject Living room Measurement scenarios * LOS : Line-of-sight Kajiwara lab. NLOS : Non-line-of-sight 9
Time-range profile Range profile Received power each distance Time-range profile Aligned Range profile by each measured time Range profile Time-range profile Kajiwara lab. 10
Measurement results (Scenario 1) Sensitivity is small from about 1m Motion filter to be applied Sensitivity is observed to 4m Time-range profile Scenarios Kajiwara lab. 11
Trajectory estimation False alarm rate is set to be less than 10-2 Estimated value is plotted Over the threshold and closest antenna Profile of signal process Threshold Trajectory estimation Estimated trajectory is in good agreement with measurement Kajiwara lab. 12
Intruder detection method Various motions are classified into four levels Intruder is to be detected Intruder exist at zone-1 (Level 3) Zone-1 Zone-2 from zone-2 to zone-1 (Level 2) from zone-1 to zone-2 (Level 1) Empty Two alarm zones Intruder detection method Estimated value is similar to actual Kajiwara lab. 13
Detection rate Detection rate of each levels for each band-width 1.0GHz 0.5GHz 0.2GHz Level 3 86.9% 84.6% 91.3% Level 2 71.2% 69.7% 60.6% Level 1 78.4% 73.6% 67.8% Empty 100% 75.0% 75.0% Total 84.2% 75.7% 73.7% *1GHz has better performance relative to other bandwidth Proposed sensor is useful for home security sensor Kajiwara lab. 14
Conclusions Use of UWB stepped-fm sensor has been suggested for home security Performance has been experimentally investigated Future study Development of detection algorithm with high accuracy Verification of availability for the case of narrow band more over Real-time signal process Investigation of influence of pet animal Kajiwara lab. 15