1. LOGO A Multi Unsymmetrical Beam Tapered Slot Ya-gi Antenna with λ/4 for PMMW Imaging  Presenter: Ya Chung Yu

2. www.themegallery.com Company Logo Out Line  Introduction  Specification  Antenna design  Multi unsymmetrical beam antenna design  Summary

3. www.themegallery.com Company Logo Introduction  Passive millimeter wave imaging (76~110GHz) Effective detection  Reveals any material: metal, liquids and gels, contraband, sheet and bulk explosives  Several millimeter resolution Efficient, easy to carry and image  Small size and portable  Single scan without changing position (multiple views with one scan)  Primary and/or secondary screening Respects Privacy  Imaging system shows 3-D black and white silhouette, which is not stored  Options for privacy blurring, remote viewing and gender specific viewing  Automatic detection option to support or replace analyst review of image Harmless  NOT X-ray technology  Only receive heat radiation

4. www.themegallery.com Company Logo  Key components of PMMW imaging system -High efficiency lens antenna -low noise amplifier (LNA) -Low bias power detector  Critical performance -Temperature resolution -Where k: Boltzmann constant T: Absolute temperature T 0 : Ambient temperature F: Noise Figure B: RF bandwidth  : Integration time -Spatial resolution depends on Lens size and feed antenna design

5. www.themegallery.com Company Logo Specification ITRI Passive Imaging System Specifications Detection distance1~3 m Spatial resolution2 cm x 2 cm Lens Diameter20 cm Focal plane distance14 cm Side-lobe Level -10 dB Feed Antenna 3 dB Beam-width 70° Feed Antenna array spacing3.74 mm Field of View22 cm x 22 cm Pixel (receiver array)11 x 11 channels Temperature resolution0.5 K System Bandwidth 20 GHz (75-95 GHz, W-band) System Noise Figurebelow 10 dB System Gain 30 dB Integration Time 20 ms Power Detector Responsivity 9.3 V/mW ADC bit number10 bits ADC Sampling Frequency100 MHz Imaging Video Frame RateUp to 30 fps Integration Time20 ms Digital Signal Processing Time10 ms Detection distance: 1~3 m Spatial resolution: 2 cm @ 1 m detection distance Temperature resolution: 0.5 K Field of View: 22 cm × 22 cm (pixel: 11 × 11) Detection distance: 1~3 m Spatial resolution: 2 cm @ 1 m detection distance Temperature resolution: 0.5 K Field of View: 22 cm × 22 cm (pixel: 11 × 11) 70 度 15cm 100cm

6. www.themegallery.com Company Logo Antenna design  Antipodal tapered slot antenna - PCB layout (duroid 5880), low cost, low losstangent - endfire radiation pattern, a pixel corresponds to an antenna  Bandwidth 20GHz (78~98GHz) - satisfy the requirement of the temperature resolution  3 dB beamwidth 70 degree - satisfy the lens specifications (focal length of 15cm & lens diameter of 20cm) Challenge problem:

7. www.themegallery.com Company Logo Multi unsymmetrical beam antenna design  Original symmetrical tapered slot ya-gi antenna form Return Loss (dB) Co-pole pattern (dB) Symmetrical pattern 3dB beamwidth 70° 90° antipodal tapered slot ya-gi directors λ/4 fan rejections at focal point of lens

8. www.themegallery.com Company Logo  Unsymmetrical beam form (perturbation method) λ/4 fan rejections (broadband structure) control traveling current phase (perturb current directions) reduced coupling interference at off axis focal plane

9. www.themegallery.com Company Logo  Left unsymmetrical tapered slot ya-gi antenna current phase of right arm is slower than left one Left part of pattern is smoother than right part Main beam shift 10° to right 3dB beamwidth is also 70°

10. www.themegallery.com Company Logo  Right unsymmetrical tapered slot ya-gi antenna current phase of left arm is slower than right one right part of pattern is smoother than left part Main beam shift 10° to left 3dB beamwidth is also 70°

11. www.themegallery.com Company Logo Comparison Sym Left Right

12. www.themegallery.com Company Logo  Feed antenna array Lens W-band Antenna DC bias DC output W-band chip (LNA & PD) λ/4 fan rejections

13. www.themegallery.com Company Logo Summary  Multi beam unsymmetrical tapered slot ya-gi antenna is useful for near field focusing lens, especially in the condition of the wider imaging range  It is easy to change radiation pattern with quarter-wavelength fan rejection structure without rotating physical angle  Reduce the area of layout and loss

14. www.themegallery.com Company Logo Thanks for Listening