This presentation on antenna aperture and pathoss is part of the Wireless communication lecture series by SARODEOVERWIRELESS Consulting.
It explains the misconception many engineers have that pathloss increases with frequency due to RF propagation losses in free space medium.
Pathloss increases with frequency due to reduction in size of the antenna aperture. it effective area to capture incident RF energy gets smaller at higher frequencies.
For example, 2.4GHz Wi-Fi is known to have larger coverage than 5GHz Wi-Fi band. This is partly due to to smaller antenna aperture of the 5GHz, but attenuation through physical structures and fading play a significant role in increased pathloss.
Watch Video on YouTube: 
https://www.youtube.com/watch?v=mmj6JhKQ0vg