# Lesson 33 — The Friis Equation

<p class="block-synopsis">The Friis equation, combining it with line of sight, and working a complete radio communication problem.</p>

**Objectives covered**

- **3.5** — I can calculate the maximum communication distance between a transmitter and receiver using the Friis and Line-of-Sight equations.

<div class="block-toc">
  <a class="bt-card bt-reading" href="../Block3Reading/Obj05/ECE215_B3_Obj05_Reading.html">
    <span class="bt-kind">Reading</span>
    <h4>The Friis Equation</h4>
    <p>The course reading for Objective 3.5.</p>
  </a>
  <a class="bt-card bt-flashcards" href="L33_Flashcards.html">
    <span class="bt-kind">Flashcards</span>
    <h4>Review deck</h4>
    <p>Key terms, equations, and ideas from this lesson, in a self-test deck.</p>
  </a>
  <a class="bt-card bt-slides" href="../_static/slides/ECE_215_Lesson33.pdf">
    <span class="bt-kind">Slides</span>
    <h4>Lesson 33 deck</h4>
    <p>The slides used in class, as a PDF.</p>
  </a>
  <a class="bt-card bt-practice" href="../downloads.html">
    <span class="bt-kind">Practice Problems</span>
    <h4>Work these before the quiz</h4>
    <p>Ungraded problems with answers, on the downloads page.</p>
  </a>
</div>