Standing Up For Standing Waves

Topic (Syllabus) from the Standing Up For Standing Waves video -

Website: http://home.windstream.net/whays101/index.html

RF Communications. Past, Present, and Future:

Milestones in RF Communications

One Hundred Years ago efficient Transmission Lines and Antennas equaled increased range

(Standing Up For Standing Waves Rule #1)

Rule #1 still applies in the 21st Century

Overview of Demonstration Equipment:

RF Source

Frequency

4 to 1 Coaxial Balun

Transmission Line

Sensors

Ideal Transmission Line Conditions:

Terminating Impedance Equals Transmission Line Impedance

Transmission Line RF Power Distribution

Transmission Line RF Voltage Distribution

Transmission Line RF Current Distribution

Standing Wave Ratio (SWR):

Technically known as Voltage Standing Wave Ratio or VSWR

Defined as a Wave that appears to be "Frozen in Time" or "Standing" on a Transmission Line

Caused by Collision of "Forward" and "Reflected" Energy Waves

Why does anybody care?

Characteristics of Transmission Lines with Standing Waves:

RF Voltage Distribution along a Transmission Line with Standing Waves

RF Current Distribution along a Transmission Line with Standing Waves

Forward and Reflected RF Power Distribution along a Transmission Line with Standing Waves

Measuring Standing Waves using RF Voltage

Measuring Standing Waves using RF Current

Measuring Standing Waves using RF Power

Visulization of a Standing Wave

Simple Resonant Dipole Antenna Characteristics:

"E" or Voltage Field Pattern

"H" or Current Field Pattern

Voltage and Current distribution along a Dipole Antenna

Directional Antenna Characteristics:

Directional Characteristics of a 3 Element Yagi Antenna

Effects of Cross-Polarization

Transmission Line Stubs:

Open Ended and Shorted 1/4 Wave Transmission Line Stubs

Open Ended and Shorted 1/2 Wave Transmission Line Stubs

Increasing Antenna Gain:

Addition of a "Reflector" Element to a Dipole Antenna

Addition of a "Director" Element to a Dipole Antenna

Non-Resonant Dipole Antenna:

Efficiency of "Reduced Length" or "Non-Resonate" Antennas

Improving "Non-Resonate" Antenna Efficiency

Conjugate Match Theorem:

Lumped Constant Line Matching using Capacitors

Lumped Constant Line Matching using Inductors

Distributed Constant Line Matching Using Open Ended Transmission Line Stub

Distributed Constant Line Matching Using Shorted Transmission Line Stub

Phase Velocity:

Measuring the Phase Velocity of a Transmission Line

Loss of Phase Velocity in different Dielectric Materials

Ferrite Beads:

Single Mode Attenuation

Common Mode Attenuation

Outer Coaxial Shield Attenuation

Series-Section Transmission Line Transformers:

1/2 Wave "Impedance Transparent" Transmission Line Sections

1/4 Wave "Impedance Inverting" Transmission Line Sections

Demonstration Review:

Open Group Questions

Revisit or variations of the above objectives

Handout:

Open in New Tab