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- This example demonstrates a simple hypothetical layered radio. The network
- contains two wireless nodes, and one of them is pinging the other.
- The simulation produces a diagram that can be open in the IDE using the anf file.
- The diagram shows the packet loss as a function of the distance between the two
- nodes in a number of different configurations. There are three parameter axes,
- and the simulation is run for all parameter combinations resulting in 24
- different curves.
- The first axis is the simulated level of detail in the physical layer. The
- example is run with the following different level of details:
- - packet domain (bits are not computed, error model computes packet error)
- - bit domain (bits are computed, error model computes erroneous bits)
- - symbol domain (symbols are computed, error model computes erroneous symbols)
- The different level of details are expected to produce very similar curves. One
- exception is that the symbol domain curves are different from the curves of the
- other domains when forward error correction is used. For modulations that have
- more than one bits per symbol, the demodulation process results in a different
- (non-independent and non-uniform) distribution of bit errors, which in turn is
- decoded differently.
- The second axis is about the forward error correction that is used in the bit
- domain. The simulation is run with and without using forward error correction.
- The used convolutional code has a code rate R = 1 / 2, and memory m = 1 with
- generator matrix G(D) = (1 1 + D). When forward error correction is used it is
- expected to increase the communication range. Note that in this example the net
- bit rate is constant, therefore the gross bit rate is increased when using
- forward error correction.
- The third axis is about the modulation that is used in the symbol domain. The
- simulation is run with the following modulations:
- - BPSK
- - QPSK
- - QAM-16
- - QAM-64
- In general, modulations with more bits per symbol tend to have smaller
- communication range.
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