Project: IEEE P Working Group for Wireless Personal Area Networks (WPANs)

Transcription

1 Project: IEEE P Working Group for Wireless Personal Area Networks (WPANs) Title: [Radiometric and Geometric Consideration for image sensor receiver] Date Submitted: [July, 2015] Source: [Md. Shareef Ifthekhar, Trang Nguyen, Nirzhar Saha, Nam Tuan Le, Mohammad Arif Hossain, Chang Hyun Hong and Yeong Min Jang] [Kookmin University] Address [Kookmin University, Seoul, Korea] Voice:[ ], FA: [ ], Re: [] July 2015 Abstract: [This document present radiometric and geometric consideration for image sensor receiver] Purpose: [Contribution to IEEE SG7r1] Notice: This document has been prepared to assist the IEEE P It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein. Release: The contributor acknowledges and accepts that this contribution becomes the property of IEEE and may be made publicly available by P Slide 1

2 Optical Camera Communications Slide 2

3 Optical Camera Communications Frame rate only 30 frames/sec Frame sampling Data is send at the rate than 100 hz to avoid flickering.... #1 #2 #15 #29 #30 1/30s 1s Slide 3

4 Camera Geometry (pin hole camera model) KR[ I C] C is the camera position in world coordinate system is any point in world coordinate system is image point of R is rotation matri between world coordinate and camera coordinate Y Z Pinhole Camera World coordinate system C y z image point Principal point Camera coordinate system Slide 4

5 Camera Camera Radiometry (Lambertian model) LED ϕ i(, y) (0 0-1) d ψ i(, y) Lens f ψ i(, y) Lambertian emission Camera Z Y World Coordinate z y ( c,y c ) r c(,y) (i,yi) Camera Coordinate It determines the object image intensity in an imaging plane Slide 5

6 Camera Radiometry and Geometry (Combine approach) LED LED ϕ i(, y) Camera FOV Yaw z (0 0-1) d f ψ i(, y) ψ i(, y) Lens Z Y World Coordinate Pitch Roll y Camera Coordinate Z Y World Coordinate z y ( c,y c ) r c(,y) (i,yi) Camera Coordinate (a) (b) Slide 6

7 Camera Radiometric Response (Irradiance to image intensity) Red Channel Green Channel Blue Channel Camera Radiometric Response Curve Image Intensity Irradiance Image sensor nonlinearly response to irradiance and generate image intensity values or piel values Slide 7

8 Simulation Parameters Parameters Value LED position [ ] (Center of the circular LED) LED diameter 170 mm Half Power emission, ϕ 70 deg Transmit power, P t 1500 mw Focal length 1.4 or 3 mm Image size Camera Principal point ( c, y c ) [ ] Skew 0 Piel edge length, s 7.1e-3 mm Slide 8

9 Effect of camera rotation (Out of Focus issue) LED LED Z Y World Coordinate z Pitch Yaw Roll y Camera Coordinate Yaw z Z Y World Coordinate y Roll Pitch Camera Coordinate (a) (b) Slide 9

10 Effect of camera rotation (Out of Focus issue) (a) Camera Rotation=[ ], imagesize= and f=1.40 mm (b) Camera Rotation=[ ], imagesize= and f=1.40 mm (c) Camera Rotation=[ ], imagesize= and f=1.40 mm Received power (dbm) Y (m) (m) (d) Camera Rotation=[ ], imagesize= and f=3.00 mm Received power (dbm) Y (m) (m) (e) Camera Rotation=[ ], imagesize= and f=3.00 mm Received power (dbm) Y (m) (m) (f) Camera Rotation=[ ], imagesize= and f=3.00 mm Received power (dbm) Y (m) (m) Received power (dbm) Y (m) (m) Received power (dbm) Y (m) (m) Fig 3. Receive power across the room (4 m2) for different rotation and focal length of a camera, where receiving plane height Z = 1500 mm. Indoor automated guided vehicle need to preprogrammed in order to ensure received signal Camera geometry is needed to ensure that Slide 10

11 Simulation Parameters Parameters Value LED position (Center of the circular LED) [ ] (LED 1) [ ] (LED 2) [ ] (LED 3) [ ] (LED 4) LED diameter 170 mm Half Power emission, ϕ 70 deg Transmit power, P t 1500 mw Focal length 1.4 and 3 mm Image size Camera Principal point ( c, y c ) [ ] Skew 0 Piel edge length, s 7.1e-3 mm Slide 11

12 Simulation Results Camera Position = [ ], Camera Rotation = [ ] and f=1.40 mm Camera Position = [ ], Camera Rotation = [ ] and f=3.00 mm Radiometric response curve has been used to transform LED irradiance on imaging plane into LED image intensity Slide 12

13 OCC Applications Indoor Positioning and Location Based Services Z Coordinator (1, Y1, Z1) (2, Y2, Z2) (3, Y3, Z3) Image z coordinate y Imaging lens Y (3, y3) (2, y2) (1, y1) Image sensor Coordinato r T # N PLC T # N-1 T # 3 IP Network Streaming Server T # 2 T # 1 Smart device Indoor Positioning World coordinate Mobile # N Mobile # 2 Mobile # 1 Guiding in museum Product Information Marketing Slide 13

14 Conclusion Camera radiometry and geometry both has been considered Impacts on OCC from camera radiometric and geometric changes have been analyzed. Out of focus issues has been identified due to camera rotation Which can not be neglect when camera movement is intense Radiometric response curve has been used to transform irradiance into image intensity Slide 14