Rayleigh fading is a reasonable model when there are many objects in the environment that scatter the radio signal before it arrives at the receiver. 

Rayleigh fading models ASSUME that the magnitude of a signal that has passed through such a communications CHANNEL will vary randomly, or fade, ACCORDING to a Rayleigh distribution the radial component of the sum of TWO uncorrelated Gaussian random variables.

Rayleigh fading is most applicable when there is no dominant PROPAGATION along a line of sight between the transmitter and receiver. If there is a dominant line of sight, Rician fading may be more applicable.

Rayleigh fading is a reasonable model when there are many objects in the environment that scatter the radio signal before it arrives at the receiver. 

Rayleigh fading models assume that the magnitude of a signal that has passed through such a communications channel will vary randomly, or fade, according to a Rayleigh distribution the radial component of the sum of two uncorrelated Gaussian random variables.

Rayleigh fading is most applicable when there is no dominant propagation along a line of sight between the transmitter and receiver. If there is a dominant line of sight, Rician fading may be more applicable.