## Real-time Spectrum Sensing for Cognitive Radio using FFT
This code simulates real-time spectrum sensing for a cognitive radio system using the Fast Fourier Transform (FFT). It generates a simulated available spectrum and performs FFT analysis to visualize spectrum occupancy and identify potential channels for transmission.
**Features:**
* Simulates spectrum occupancy with three sinusoidal signals representing different frequencies.
* Calculates the FFT of the simulated spectrum to obtain its frequency domain representation.
* Plots both the time-domain (available spectrum) and frequency-domain (spectrum sensing) representations for visual analysis.
**Requirements:**
* MATLAB https://www.mathworks.com/
**Instructions:**
1. **Save the code:** Save the provided code as a `.m` file (e.g., `cognitiveradio.m`).
2. **Run the code:** Open MATLAB and navigate to the directory containing the saved file. Execute the script using the `run` command:
```matlab
run cognitiveradio.m
