Wifi Signal Strength

wifi.py

import subprocess
import matplotlib.pyplot as plt
import threading


# Use a nicer style for the plot
plt.style.use('seaborn-darkgrid')


def get_wifi_data():
    # Obtain WiFi data using airport command
    result = subprocess.check_output(['/System/Library/PrivateFrameworks/Apple80211.framework/Versions/Current/Resources/airport', '-I']).decode('utf-8')
    rssi = int([line.split(":")[1].strip() for line in result.split('\n') if "agrCtlRSSI" in line][0])
    noise = int([line.split(":")[1].strip() for line in result.split('\n') if "agrCtlNoise" in line][0])
    
    return rssi, noise, rssi-noise


def plotter():
    i = 0
    while True:
        rssi, noise, snr = get_wifi_data()

        x.append(i)
        y_rssi.append(rssi)
        y_noise.append(noise)
        y_snr.append(snr)

        line_rssi.set_xdata(x)
        line_rssi.set_ydata(y_rssi)

        line_noise.set_xdata(x)
        line_noise.set_ydata(y_noise)

        line_snr.set_xdata(x)
        line_snr.set_ydata(y_snr)

        # Draw vertical line if a room change is detected
        if room_changes.get(i, None):
            ax_rssi.axvline(x=i, color='gray', linestyle='--')
            ax_noise.axvline(x=i, color='gray', linestyle='--')
            ax_snr.axvline(x=i, color='gray', linestyle='--')
            
            # Annotate the room name by the line on the rssi graph
            ax_rssi.annotate(room_changes[i], (i, ax_rssi.get_ylim()[1]), textcoords="offset points", xytext=(0,5), ha='center', fontsize=8, color='gray', va='bottom')

        # Update the axes to fit all data and redraw
        for ax in [ax_rssi, ax_noise, ax_snr]:
            ax.relim()
            ax.autoscale_view()

            # Adjust x-axis to show all data points
            if x:
                ax.set_xlim([0, x[-1]])

            # Y-axis settings
            if ax == ax_rssi:
                y_min = min(-60, -70, min(y_rssi))  # Include thresholds -60 and -70
                y_max = max(-60, -70, max(y_rssi))
                ax.set_ylim(y_min, y_max)
            elif ax == ax_noise:
                ax.set_ylim(min(y_noise), max(y_noise))
            elif ax == ax_snr:
                y_min = min(15, 25, min(y_snr))  # Include thresholds 15 and 25
                y_max = max(15, 25, max(y_snr))
                ax.set_ylim(y_min, y_max)

        plt.draw()
        plt.pause(1)
        i += 1


# Initial Setup for live graph
plt.ion()
fig, (ax_rssi, ax_noise, ax_snr) = plt.subplots(3, 1, sharex=True)

x, y_rssi, y_noise, y_snr = [], [], [], []
line_rssi, = ax_rssi.plot(x, y_rssi, color='blue', label="RSSI")
line_noise, = ax_noise.plot(x, y_noise, color='green', label="Noise")
line_snr, = ax_snr.plot(x, y_snr, color='red', label="SNR")

# Initial axis settings and quality lines
for ax in [ax_rssi, ax_noise, ax_snr]:
    ax.legend()
    ax.set_xlim(0, 10)
    ax.set_ylim(-100, 100)

# Coloring based on thresholds
ax_rssi.axhspan(-60, ax_rssi.get_ylim()[1], color='green', alpha=0.1, label="Good RSSI Zone")
ax_rssi.axhspan(-70, -60, color='yellow', alpha=0.1, label="Fair RSSI Zone")
ax_rssi.axhspan(ax_rssi.get_ylim()[0], -70, color='red', alpha=0.1, label="Poor RSSI Zone")

ax_snr.axhspan(25, ax_snr.get_ylim()[1], color='green', alpha=0.1, label="Excellent SNR Zone")
ax_snr.axhspan(15, 25, color='yellow', alpha=0.1, label="Good SNR Zone")
ax_snr.axhspan(ax_snr.get_ylim()[0], 15, color='red', alpha=0.1, label="Poor SNR Zone")

ax_rssi.set_ylabel('dBm')
ax_noise.set_ylabel('dBm')
ax_snr.set_ylabel('dB')

# To track room changes
room_changes = {}

def listen_for_input():
    global room_changes
    while True:
        room = input("Enter room name: ")
        if room:
            room_changes[len(x)] = room

# Starting the listening thread
threading.Thread(target=listen_for_input).start()

# Start the plotting
plotter()