Contractors shall include fade margin
calculations with the proposal, showing the antenna sizes, system gains, and system losses etc.
This implies that the average received signal is much higher than the squelch level; therefore the link availability is quite good even with low fade margin
Once fire required fade margin
(the depth of fade, expressed in decibels, which a microwave link can tolerate while still maintaining acceptable circuit quality) is achieved, Link Calc users can, within seconds, generate a fully itemized bill o materials.
Systems with the highest fade margin
usually go longer distances.
Additional fade margin
must be allocated in order to increase the system availability.
Multitap surface acoustic wave-based and application-specific integrated circuit-controlled adaptive time domain equalizers are deployed as a standard part of the demodulator circuitry to maximize the correction of intersymbol interference due to multipath fading and to achieve dispersive fade margin
specifications equal to and, in many cases, better than systems using lower modulation schemes.
To overcome this fading, and the loss due to distance, more fade margin
can be built into the path by using equipment with higher system gain.
The fade margin
for the CCIR model would be the dB value of the rain loss which was 180 dB - FSL - vapor losses.