freesopy 2.0.2

This is a Python package for the implementation of various equations of Free Space Optical Communication

Freesopy

A Python package for the implementation of various equations of Free Space Optical Communication

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Freesopy is designed to simplify the implementation of various mathematical equations used in Free Space Optical Communication. It provides easy-to-use functions that can be integrated into your projects.

Structure

Create at least 4 seperate python files in same directory :

1. main.py
2. transmitter.py
3. reciever.py
4. environment.py

transmitter.py

xt =          # location of transmitter
yt =          # location of transmitter
zt =          # location of transmitter
p_t =         # transmitted power
d_t =         # diameter of transmitter antenna
theta_d =     # angle of divergence
w_0 =         # initial beam waist
theta_semi =  # Semi-angle at half power of the LED's radiation pattern (in degrees)

receiver.py

xr =                 # location of receiver
yr =                 # location of receiver
zr =                 # location of receiver
d_r =                # aperture diameter of receiver
p_r =                # power received by receiver
n_0 =                # noise power
T =                  # temperature of receiver
B =                  # Bandwidth
r_load =             # Load resistance
i_photo =            # Photocurrent
i_shot_squared =     # Shot noise squared
i_thermal_squared =  # thermal noise squared
Adet =               # Detector physical area of the photodetector (PD) (in square meters)
Ts =                 # Gain of an optical filter
index =              # Refractive index of the lens at the photodetector.
FOV =                # Field of View (in degrees) of the receiver.

environment.py

lx =              # dimensions of room 
ly =             # dimensions of room 
lz =            # dimensions of room 
wl =              # wavelength 
sigma_s =        # standard deviation due to scintillation 
f =              # frequency 
d_range =        # Tuple defining the minimum and maximum distance in metres 
num_points =      # Number of distance points to generate 
rho =            # Reflection coefficient of the walls, representing how much light is reflected. 
delta_t =        # Time resolution in nanoseconds 

Usage

You can import Freesopy and the python files containing information about Transmitterr(transmitter.py),reciever(reciever.py) and Environment(environment.py) in your main.py file as:

import freesopy as fso
from transmitter import *
from receiver import *
from environment import *

Some General Equations

Calculate Received Power

Power_received = fso.calculate_received_power(P_t, D_r, d)

Calculate SNR

SNR = fso.calculate_snr(P_r, N_0)

Calculation of Losses

Misalignment Loss

misalignment_loss = fso.pointing_misalignment_loss(d, sigma_p, pt)

General Graphs and Calculations

SNR Calculations

I_photo = fso.calculate_photocurrent(P_received, responsivity)

I_thermal_squared = fso.calculate_thermal_noise(T, B, R_load)

I_shot_squared = fso.calculate_shot_noise(I_photo, B)

SNR = fso.calculate_SNR(I_photo, I_shot_squared, I_thermal_squared)

fso.plot_SNR(P_received, SNR)

Free Space Path Loss (FSPL)

fso.plot_fspl(f, d_range, num_points)

Divergence of Optical Beam

fso.plot_beam_divergence(w_0, lambda_light, d_range, num_points)

Channel Modelling

Simulating the LOS channel gain

fso.los_channel_gain(theta, P_total, Adet, Ts, index, FOV, lx, ly, lz, h, XT, YT)

Plotting the Optical Power Distribution in a Diffuse Channel

fso.optical_power_distribution(P_total, rho, lx, ly, lz, FOV, Adet, Ts, G_Con, theta)

Simulation of the Drms of a Diffuse Channel

fso.calculate_Drms_3D(C, theta, P_total, Adet, rho, Ts, index, FOV, lx, ly, lz, delta_t)