Welcome to Atmospheric Effects on Electromagnetic Systems!


Learning Objectives



The table below provides a roadmap to the learning materials. We recommend that you start at the beginning and go through the topics in order. However, each topic has a link so that you can revisit the material as needed.

Module Title
1. Introduction to Electromagnetic Radiation  1.0 Basic EM Concepts
 1.1 The Electromagnetic spectrum
 1.2 How radio works and how EM radiation is represented
 1.3 Modes of Transmission
 1.4 Refraction: What Causes EM waves to bend? Advanced material
Course Introduction
Podcast 1.0 (11 min)
Podcast 1.1 (7 min)
Podcast 1.2 (8 min)
Podcast 1.3 (7 min)
2. HF Radiation

How the ionosphere (upper atmosphere) affects communications in the Very Low Frequency (VLF) to High Frequency (HF) bands

 2.1 Introduction to HF and Lower Frequencies
 2.2 The Ionosphere and the Sun
 2.3 HF Radiation: Choosing the right frequency; HF models
 2.4 Space weather
Podcast 2.1 (13 min)
Podcast 2.2 (9 min)
Podcast 2.3 (20 min)
Podcast 2.4 (20 min)

VHF, UHF and EHF Radiation

How the troposphere (lowest 10 kilometers) affects radar and communication systems in the Very High Frequency (VHF), Ultra High Frequency (UHF) and Extremely High Frequency (EHF or microwave) bands.

 3.1 Basic refraction principles
 3.2 Types of Ducts
 3.3 Duct Formation Mechanisms
 3.4 Skip Zones, Holes and Interference Patterns
 3.5 Global Scale Refracting Effects
 3.6 Synoptic Scale Refraction Effects
 3.7 Mesoscale and Local Refraction Effects
Podcast 3.1 (12.5 min) 3.1a (11 min) 3.1b (8 min) 3.1c (12 min)
Podcast 3.2 (7 min)
Podcast 3.3 (14 min)
Podcast 3.4 (11 min)
Podcast 3.5 (6 min)
Podcast 3.6 (10 min)
Podcast 3.7 (7 min)
4. Evaporation Ducts

How the atmospheric surface layer (lowest 50 meters) affects radar in the UHF and EHF (microwave) bands.

 4.1 Evaporation Duct characteristics
 4.2 Evaporation Duct effects
 4.3 Factors affecting the Evaporation Duct
 4.4 Evaporation Duct Climatology
Podcast 4.1(8.5 min)
Podcast 4.2 (9.5 min)
Podcast 4.3 (18 min)
Podcast 4.4 (7 min)

If you have questions, please feel free to contact Dr. Peter Guest, Naval Postgraduate School at pguest@nps.edu.