Channel Model

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A basic channel model simulator that can be used to help evaluate, design, and test various signals, waveforms, and algorithms. This model allows the user to set the voltage of an AWGN noise source (), a (normalized) frequency offset (), a sample timing offset (), and a seed () to randomize or make reproducible the AWGN noise source. Multipath can be approximated in this model by using a FIR filter representation of a multipath delay profile with the parameter. To simulate a channel with time-variant channel, use Channel Model 2.

Parameters

(R): Run-time adjustable

Noise Voltage (R)
The AWGN noise level as a voltage (to be calculated externally to meet, say, a desired SNR).
Frequency Offset (R)
The normalized frequency offset. 0 is no offset; 0.25 would be, for a digital modem, one quarter of the symbol rate.
Epsilon (R)
The sample timing offset to emulate the different rates between the sample clocks of the transmitter and receiver. 1.0 is no difference.
Taps (R)
Taps of a FIR filter to emulate a multipath delay profile. Default is 1+1j meaning a single tap, and thus no multipath.
Seed
A random number generator seed for the noise source.
Block Tag Propagation
If true, tags will not be able to propagate through this block.

Example Flowgraph

Insert description of flowgraph here, then show a screenshot of the flowgraph and the output if there is an interesting GUI. Currently we have no standard method of uploading the actual flowgraph to the wiki or git repo, unfortunately. The plan is to have an example flowgraph showing how the block might be used, for every block, and the flowgraphs will live in the git repo.


Source Files

C++ files
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Header files
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Public header files
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Block definition
TODO