This repository implements the simulations tools for computing the Packet Loss Ratio (PLR) of slotted random access schemes.
The following schemes are currently supported:
- CRDSA: Contention Resolution Diversity Slotted ALOHA, introduced in this 2007 IEEE paper
- MF-CRDSA: Multi-Frequency Contention Resolution Diversity Slotted ALOHA, introduced in this 2017 IEEE paper
To reproduce the 3-replicas curves of Fig. 8 in the 2017 paper, one can use the following code block example:
using SlottedRandomAccess
using PlotlyBase # This is not part of the package env
# Generic parameters
common = (;M = 4, coderate = 1/3, power_strategy = SamePower)
coding_gain = common.coderate * log2(common.M) |> x -> -10log10(x)
line_colors = [ # Use to match the line colors
"rgb(93, 146, 191)", # 6dB, blue
"rgb(233, 71, 72)", # 9dB, red
"rgb(113, 191, 109)", # 12dB, green
]
ebno_max_vec = [6,9,12]
# Define the load vector
load = .1:.1:2
### Create the CRDSA simulations
crdsa_sims = map(1:3) do idx
ebno_max = ebno_max_vec[idx]
line_color = line_colors[idx]
# Define the RA scheme to use
scheme = CRDSA{3}()
# Define the power distribution for the replicas
power_dist = LogUniform_dB(2 - coding_gain, ebno_max - coding_gain)
# Create the simulation object
sim = PLR_Simulation(load;
common...,
power_dist,
scheme,
nslots = 100,
)
# Add information to customize the plot to the simulation object
add_scatter_kwargs!(sim;
name = "N<sub>rep</sub> = 3, [E<sub>b</sub>N<sub>0</sub>]<sub>max</sub> = $(ebno_max)dB",
line_color,
line_dash = :solid,
marker_symbol = :square,
)
simulate!(sim) # Compute the packet loss ratio
end
### Create the MF-CRDSA curves
mf_crdsa_sims = map(1:3) do idx
ebno_max = ebno_max_vec[idx]
line_color = line_colors[idx]
# Define the RA scheme to use
scheme = MF_CRDSA{3}()
# Define the power distribution for the replicas
power_dist = LogUniform_dB(2 - coding_gain, ebno_max - coding_gain)
# Create the simulation object
sim = PLR_Simulation(load;
common...,
power_dist,
scheme,
nslots = 99,
)
# Add information to customize the plot to the simulation object
add_scatter_kwargs!(sim;
name = "MF, N<sub>rep</sub> = 3, [E<sub>b</sub>N<sub>0</sub>]<sub>max</sub> = $(ebno_max)dB",
line_color,
line_dash = :dash,
marker_symbol = :diamond
)
simulate!(sim) # Compute the packet loss ratio
end
# Plot the MF-CRDSA and CRDSA curves together
Plot(vcat(crdsa_sims, mf_crdsa_sims); xaxis_dtick = .2)Which should generate something similar to the following picture:
