What is the channel model used in the Wireless sources in rfLib?

Hello, community

i'm aware rfLib has several modulated sources, such as Zigbee, LTE and 802.11. While testing Zigbee source, I saw that I can specify SNR. After obtaining the simulation results, I am able to observe BER measure. 

My doubt is: What is the chanel model used in the Zigbee and other Wireless sources available in rfLib (AWGN + Rayleigh, i.e.)? I'm asking this beacuse I'm assuming that those sources provide the standard modulated frame + chanel effects to the DUT.

But why all this? I have a BER vs SNR graph for Zigbee standard. I'm trying to understand the SNR that can be set in the Zigbee source compared to the computed BER that I receive when checking the results. This way I can compared BER vs SNR obtained in the simulations.

Thanks!

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