Channel Models

This module provides channel models for simulating signal transmission through various communication media. It supports three main categories of channels:

Wireless

Models for wireless radio channels, including additive white Gaussian noise (AWGN), flat fading with spatial correlation, Rayleigh block fading, and standardized 3GPP models (TDL, CDL, UMi, UMa, RMa) from TR 38.901. These models generate channel impulse responses (CIRs) that can be applied in the time domain or frequency domain (OFDM). The module also supports loading externally generated CIRs from datasets.

Optical

Models for fiber optical communication channels. The split-step Fourier method (SSFM) simulates signal propagation through single-mode fibers, accounting for attenuation, chromatic dispersion, and Kerr nonlinearity. An Erbium-doped fiber amplifier (EDFA) model is provided for simulating lumped amplification with amplified spontaneous emission (ASE) noise.

Discrete

Models for channels with discrete input/output alphabets, useful for information-theoretic analysis and coded system simulations. Includes the binary symmetric channel (BSC), binary erasure channel (BEC), binary Z-channel, and a general binary memoryless channel. These models support both hard outputs and soft log-likelihood ratio (LLR) outputs.