User's Manual

Appendix A. Radio Signal Propagation
User's Guide A-8 BreezeNET BU-DS.11/RB-DS.11
Figure A-6. Multipath Reception
Bad Line of Sight
An optical line of sight exists if an imaginary straight line can connect the antennas on
either side of the link.
Radio wave clear line of sight exists if a certain area around the optical line of sight
(Fresnel zone) is clear of obstacles. A bad line of sight exists if the first Fresnel zone
is obscured.
• Link Budget Calculations
• Weather conditions (rain, wind, etc.)
At high rain intensity (150 mm/hr), the fading of an RF signal at 2.4 GHz may reach a
maximum of 0.02 dB/Km. Wind may cause fading due to antenna motion.
• Interference
Interference may be caused by another system on the same frequency range, external
noise, or some other co-located system.
The Line of Sight Concept
An optical line of sight exists if an imaginary straight line can be drawn connecting the
antennas on either side of the link.
Clear Line of Sight
A clear line of sight exists when no physical objects obstruct viewing one antenna
from the location of the other antenna.