The advancement of technology in detecting individuals and objects is actively being pursued beyond the visible spectrum, leveraging wireless communication to identify objects in obscured areas. This approach offers the distinct advantage of not necessitating a direct line of sight, unlike traditional camera-based sensing methods. Current research efforts aim to utilize this technology in a range of applications, such as indoor positioning and activity monitoring. However, these studies primarily involve sensing within high-frequency bands such as Wi-Fi or Bluetooth, which present limitations in terms of short sensing distances and low transmittance rates. Given these challenges, our study concentrates on calculating the Power Spectral Density (PSD) in the 433MHz band to detect the presence of individuals nearby. Our findings demonstrate the real-time detection of individuals passing between transmitter and receiver nodes with a 95% probability