This code creates an instance of the RtlSdr class, which represents an RTL-SDR device, and sets the center frequency of the device to 101.1 MHz using the center_freq property. It also sets a step size for the frequency changes in Hz. Next, the code initializes Pygame and creates a window using the pygame.display.set_mode() function. It also sets…

RTL-SDR-Signal-Detection.py

import rtlsdr
import pygame
import time

# Create an instance of the RtlSdr class
sdr = rtlsdr.RtlSdr()

# Set the center frequency of the RTL-SDR device (in Hz)
sdr.center_freq = 101.1e6

# Set the sample rate of the RTL-SDR device (in Hz)
sdr.sample_rate = 2.4e6

# Set the gain of the RTL-SDR device (in dB)
sdr.gain = 'auto'

# Set the bandwidth of the RTL-SDR device (in Hz)
sdr.bandwidth = 2.4e6

# Set the step size (in Hz) for frequency changes
step_size = 100e3

# Initialize Pygame
pygame.init()

# Set the window size
window_size = (400, 300)

# Create the window
window = pygame.display.set_mode(window_size)

# Set the window title
pygame.display.set_caption("RTL-SDR Signal Detection")

# Set the background color
bg_color = (0, 0, 0)

# Set the signal color
sig_color = (0, 255, 0)

# Run the event loop
running = True
while running:
    # Check for key events
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            running = False
        elif event.type == pygame.KEYDOWN:
            if event.key == pygame.K_UP:
                # Increase the center frequency by the step size
                sdr.center_freq += step_size
            elif event.key == pygame.K_DOWN:
                # Decrease the center frequency by the step size
                sdr.center_freq -= step_size
    
    # Read IQ samples from the RTL-SDR device
    samples = sdr.read_samples(1024)

    # Calculate the power spectrum of the samples
    power_spectrum = abs(samples)**2

    # Check if the signal strength is above a certain threshold
    if power_spectrum.mean() > 100:
        # Signal is detected
        sig_detected = True
    else:
        # Signal is not detected
        sig_detected = False

    # Clear the window
    window.fill(bg_color)

    # Draw the center frequency on the window
    text = f"Frequency: {sdr.center_freq / 1e6:.3f} MHz"
    font = pygame.font.Font(None, 36)
    text_surface = font.render(text, True, (255, 255, 255))
    window.blit(text_surface, (10, 10))

    # Draw a rectangle on the window to indicate the presence of a signal
    if sig_detected:
        pygame.draw.rect(window, sig_color, (10, 50, 380, 240))

    # Update the window
    pygame.display.update()

# Quit Pygame
pygame.quit()

you might want to install these

sudo apt-get install python3-scipy
sudo apt-get install python3-numpy
sudo apt-get install python3-matplotlib
sudo apt-get install python3-pyrtlsdr

also
wget https://github.com/roger-/pyrtlsdr/archive/master.zip
unzip master.zip
cd pyrtlsdr-master
python3 setup.py install