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Generates a Rician selective-fading profile for the multipath channel. The envelope for the first path statistically obeys the Rician distribution, while the envelope for the remaining path obeys the Rayleigh distribution implemented using the Jakes model.


number of paths

The number of paths in the simulated multipath channel. A fading profile is generated for each of these paths.

Default: 1


rician parameter k

The desired ratio, in dB, of the dominant line-of-sight (LOS) path to the scattering component. A large positive value of k represents a strongly additive white Gaussian noise channel, while a large negative value of k represents a Rayleigh fading (predominantly scattering) channel.

Mathematical definition of Rician parameter k

Default: 0


profile length

The number of complex-valued fading profile samples (having Rician-distributed envelopes) to generate.

Default: 1000


sampling frequency

The system sample rate, in hertz (Hz). This rate is the product of the symbol rate × samples per symbol.

Default: 1


doppler spread

The desired input Doppler spread f m of the channel, in hertz (Hz).

This parameter denotes the measure of the spectral broadening caused by the time rate of change of the channel. Doppler spread is defined as the range of frequencies over which the received Doppler spectrum is essentially nonzero. When a pure sine tone at frequency f c is transmitted, the received signal spectrum, called the Doppler spectrum, has components in the range (f c - f m ) to (f c + f m ). The Doppler spread is related to the mobile velocity v, carrier frequency f c , and the speed of light c by the relation f m = v f c /c.


The inverse of the Doppler spread T c = 1 / 16 π f m (known as the coherence time) is the time duration over which the channel impulse response is essentially invariant.

Default: 0.01


seed in

The initial state for generating the fading profile. If seed in is set to -1, the generated fading profile is randomly chosen during every call when reset? is set to TRUE. Otherwise, the generated fading profile returns the same set of fading coefficients when reset? is set to TRUE. The seed in value is used only for the first call or when reset? is set to TRUE.

Default: -1


error in

Error conditions that occur before this node runs. The node responds to this input according to standard error behavior.

Default: no error


fading variance

The desired variance of the complex-valued Rician distributed fading profile.

Default: 1



A Boolean that determines whether the fading profile generation is reset on subsequent calls to this node.

TRUE Resets the fading profile generation on every call to this node.
FALSE Continues generating the fading profile from the previous iteration on subsequent calls.

Default: TRUE


fading profile

A two-dimensional array of complex-valued coefficients. The number of rows corresponds to the number of paths in the channel, and the number of columns is equal to the profile length. Wire this parameter to MT Apply Fading Profile to apply this fading profile to a baseband I/Q signal.


seed out

The internal state of the node at the end of generation of the fading profile for the current iteration.


error out

Error information. The node produces this output according to standard error behavior.