Polarization in Nature, Technology and Radio David Conn VE3KL I have conducted a study to address the problem of noise in urban environments and will share my results with you tonight. I will give you two graphs that you can use at home to evaluate signals and noise using a simple S meter A method that you can use easily to evaluate your own noise environment A method that you can use to evaluate the quality of the ionosphere at any give time. Some methods to control received noise The Shannon Hartley limits 1932 Chevy ? Credits http://www.polarization.com/land/land.html http://www.windows.ucar.edu/tour/link=/earth/images/earth_magneto_image.html&edu=high 12/1/2018 David Conn VE3KL QCWA Sept 2006

David Conn VE3KL QCWA Sept 2006 Acknowledgements Wild Rose Chapter 151 QCWA QCWA Chapter 70 Members Ken Oelke VE6AFO Graham Ide VE3BYT Clare Fowler VE3NPC Ken Pulfer VE3PU Doug Leach VE3XK 12/1/2018 David Conn VE3KL QCWA Sept 2006

David Conn VE3KL QCWA Sept 2006 What is Polarization ? 12/1/2018 David Conn VE3KL QCWA Sept 2006

David Conn VE3KL QCWA Sept 2006 Light and Radio Waves Composed of Electric Fields, E E at right angles to direction of propagation E can be Horizontal, Vertical, Circular.. Unpolarized…….. The Sun Demo 12/1/2018 David Conn VE3KL QCWA Sept 2006

Why is Polarization Important ? The Ionosphere and materials change the polarization of Radio Waves Operation of Lasers, LCD displays, Sun Glasses Medical research…. Diabetes Biology .. Insects.. 12/1/2018 David Conn VE3KL QCWA Sept 2006

The Basics … #1 [Reflection..Refraction] Standing Wave Region SWR Air Reflected Wave Water Refracted Wave Incoming Plane Wave 12/1/2018 David Conn VE3KL QCWA Sept 2006

The Brewster Angle [E in plane of the Screen] 53 Degrees NO Reflection Like a matched Load SWR = 1:1 Air Water Refracted Wave Incoming Plane Wave of Light 12/1/2018 David Conn VE3KL QCWA Sept 2006

David Conn VE3KL QCWA Sept 2006 Basics.. #2 The Wire Grid Polarizer Horizontal Wires Incoming Unpolarized Light/Radio Wave Vertically Polarized Horizontally Polarized 12/1/2018 David Conn VE3KL QCWA Sept 2006

Reflector or Transmitter The Wire Grid Reflector or Transmitter Horizontal Wires Vertically Polarized Wave Circularly Polarized Wave Horizontally Polarized 12/1/2018 David Conn VE3KL QCWA Sept 2006

David Conn VE3KL QCWA Sept 2006 Examples Rainbows Sun Glasses Liquid Crystal Displays The Magnetosphere Four Antennas Insects 12/1/2018 David Conn VE3KL QCWA Sept 2006

David Conn VE3KL QCWA Sept 2006 Rainbows Are they Polarized ? 12/1/2018 David Conn VE3KL QCWA Sept 2006

David Conn VE3KL QCWA Sept 2006 YES…But Why? Horizontal At Top Note the Double Rainbow 12/1/2018 David Conn VE3KL QCWA Sept 2006

David Conn VE3KL QCWA Sept 2006 Here is Why Unpolarized Light from the Sun Water Droplet 42 degrees Brewster Angle Vertical Polarized perpendicular to the Screen Horizontal 12/1/2018 David Conn VE3KL QCWA Sept 2006

Polarized Sunglasses Transmit Vertically Polarized Light Vertical lost due to Brewster Horizontal lost by Glasses Wire Grid Angle Important Brewster Angle Horizontally Polarized 12/1/2018 David Conn VE3KL QCWA Sept 2006

David Conn VE3KL QCWA Sept 2006 Liquid Crystals cyanobiphenyl materials 1888 Liquid Crystal Credits http://www.kth.se/fakulteter/TFY/kmf/lcd/lcd~1.htm http://nobelprize.org/educational_games/physics/liquid_crystals/history/ 12/1/2018 David Conn VE3KL QCWA Sept 2006

David Conn VE3KL QCWA Sept 2006 LCD Display http://nobelprize.org/educational_games/physics/liquid_crystals/history/ 12/1/2018 David Conn VE3KL QCWA Sept 2006

Polarization in the Ionosphere Big Impact on Radio and EME Earth’s Magnetic Field Linear Polarization (45 degrees tilt) Elliptical Polarization 50 MHz Electrons in the Ionosphere 70 Km 12/1/2018 David Conn VE3KL QCWA Sept 2006

Polarization in the Ionosphere Faraday Rotation Horizontal Polarization Input Earth’s Magnetic Field Vertical Polarization Output A Horizontal Dipole will NOT Talk to a Horizontal Dipole. Electrons in the Ionosphere 12/1/2018 David Conn VE3KL QCWA Sept 2006

Some Examples of Circularly Polarized Antennas Two Crossed Dipoles …… Basic Two Crossed Dipoles …… Very simple The Classic Helix …. Complex The Skew Planar …. Very Complex 12/1/2018 David Conn VE3KL QCWA Sept 2006

David Conn VE3KL QCWA Sept 2006 Two Crossed Dipoles Horizontal Antenna λ/4 LHC 50 Watts Transmitter 100 Watts Direction of Propagation 50 Watts Vertical Antenna Antennas Fed In-Phase (Details not shown) 12/1/2018 David Conn VE3KL QCWA Sept 2006

A Simple Circularly Polarized Antenna Two crossed dipoles Connected in parallel One LONGER than the other Radiates into the Screen Zin = 50 Ohms 12/1/2018 David Conn VE3KL QCWA Sept 2006

David Conn VE3KL QCWA Sept 2006 The Helix Antenna Invented by John Kraus Used by Amateurs for Satellite Communications Difficult to Analyze Relatively High Gain …. 15 dBc 12/1/2018 David Conn VE3KL QCWA Sept 2006

David Conn VE3KL QCWA Sept 2006 The Helix Antenna 12/1/2018 David Conn VE3KL QCWA Sept 2006

The Skew Planar Antenna 900 MHz Beacon Applications A Story of its Own Researched extensively by Graham Ide (VE3BYT) Omni Directional and Circularly Polarized First reported in QST 1960’s Not used again until Graham got interested 12/1/2018 David Conn VE3KL QCWA Sept 2006

The Skew Planar Antenna 70 Cm Beacon Applications VE3BYT 12/1/2018 David Conn VE3KL QCWA Sept 2006

Some Insects have complex polarized eyes http://xray.optics.rochester.edu/workgroups/cml/opt307/spr04/greg/ 12/1/2018 David Conn VE3KL QCWA Sept 2006

David Conn VE3KL QCWA Sept 2006 Summary The Concepts and Use of Polarized Signals Span many disciplines Two Ideas Presented: The Brewster Angle The Wire Grid 12/1/2018 David Conn VE3KL QCWA Sept 2006

David Conn VE3KL QCWA Sept 2006 VY 73 David 12/1/2018 David Conn VE3KL QCWA Sept 2006

Where to Get More Information and Credits http://webphysics.davidson.edu/physlet_resources/dav_optics/Examples/polarization.html http://en.wikipedia.org/wiki/Liquid_crystal_display http://www.ngsir.netfirms.com/englishhtm/Lissajous.htm Fields and Waves in Communication Electronics: Ramo, Whinnery, Van Duzer ; John Wiley, third edition, 1994, ISBN 0-0471-58551-3 12/1/2018 David Conn VE3KL QCWA Sept 2006