What is frequency selective fading

Selective fading or frequency selective fading is a radio propagation anomaly caused by partial cancellation of a radio signal by itself — the signal arrives at the receiver by two different paths, and at least one of the paths is changing (lengthening or shortening).

1. What is frequency selective fading *?
2. What is flat fading and frequency selective fading?
3. What are the three types of fading?
4. What causes selective fading?

What is frequency selective fading *?

Frequency selective fading occurs when the symbol length is shorter than the delay spread, or equivalently when signal bandwidth is larger than the channel bandwidth.

What is flat fading and frequency selective fading?

Flat Fading is caused by absorbers between the two antennae and is countered by antenna placement and transmit power level. Page 4. Frequency Selective Fading. Frequency selective fading is caused by reflectors between the transmitter and receiver creating multi-path effects.

What are the three types of fading?

The Fading types are divided into large scale fading and small scale fading (multipath delay spread and doppler spread). Flat fading and frequency selecting fading are part of multipath fading where as fast fading and slow fading are part of doppler spread fading.

What causes selective fading?

Multipath or selective fading occurs when the atmospheric conditions cause the various rays of the radio wave to be reflected and/or refracted over the path until some arrive at the receiving antenna out of phase with the main or direct wave.