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Talk:Rician fading

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The second part of the definition which states that Rician fading occurs when one path is much stronger than others is bugging me. If the reflection is nearly as strong as the main path (e.g. over flat wet ground) the fading will be worse because the two paths will cancel each other almost entirely. If the reflection is much weaker the fading will also be much weaker.

71.174.240.170 23:46, 25 April 2007 (UTC)[reply]

Not worse than Rayleigh fading, where there is no stronger path, meaning that the "risk" for cancellation is higher. Mange01 22:57, 30 April 2007 (UTC)[reply]
Furthermore the second path may be in phase with the first one (giving constructive interference), thus resulting in an amplified signal at the receiver. Fakk 19:49, 25 July 2007 (UTC)[reply]

The definition states that Rician fading occurs when at least two paths arrive at the receiver. If I recall correctly, we can say that amplitudes of the channel impulse response follow a Rician distribution only if the channel impulse response is a complex Gaussian random process (with non-zero mean). To state this, either we use the central limit theorem (due to the many paths characterizing the channel) or we have to know a priori that the channel impulse response is such a random process. So, have we to specify that Gaussian thing or does Rician fading occur even in other situations? Fakk 19:49, 25 July 2007 (UTC)[reply]

Rician fading is in no sense limited to the case where there are exactly two paths. On the contrary, a line of sight path may be superposed by a manifold of scattering paths which overall generates the Rician distribution for the amplitude. The statement with the two paths is misleading, since this is only a special case. 141.24.93.165 (talk) 08:21, 9 April 2008 (UTC)[reply]