INSTALLATION AND MAINTENANCE MANUAL
LYNX
E1 FAMILY
LICENSED & SPREAD SPECTRUM RADIOS
JUNE 2001
PAGE 3-34
SECTION 3: INSTALLATION & ADJUSTMENTS
3.3.5
Availability Calculation
Availability of the microwave path is a measure of the percent of the time that the link will operate
without producing an excessive BER due to multipath fading. In the absence of direct interference,
availability is affected by the following:
- Path length
- Fade margin
- Frequency (1.5, 2.4 GHz or 5.8 GHz in the case of the
Lynx
radios)
- Terrain (smooth, average, mountainous)
- Climate (dry, temperate, hot/humid)
Depending on the type of traffic carried over the link, the system designer may wish to design for a
specific availability. For example, if the data or voice traffic that is carried by the radio is critical then
it may be designed for a very high availability (e.g. 99.999% or 5.3 minutes of outage per year). To
improve availability, for example, the fade margin can be increased by making the path shorter, or
by using higher gain antennas in conjunction with lower loss feeders (by using high quality
transmission line or shortening feed length).