Typically the higher the frequency the higher the path loss through air and through obstrucitons like walls. That's why 900 MHz is preferable for long distance communications and for penetrating through buildings, whereas 2.4 GHz and 5 GHz technologies exhibit significantly less range and higher losses through walls. 60 GHz is much higher frequency, so almost no signal penetrates through walls and even in the air the losses are quite high.
Drones are, in essence, flying autonomous vehicles. Pros and cons surrounding drones today might well foreshadow the debate over the development of self-driving cars. In the context of a strongly regulated aviation industry, "self-flying" drones pose a fresh challenge. How safe is it to fly drones in different environments? Should drones be required for visual line of sight – as are piloted airplanes? Join EE Times' Junko Yoshida as she moderates a panel of drone experts.