Mobile communication systems continuously transmit radio frequency (RF) signals, which contain small amounts of electromagnetic energy in the surrounding environment. This project focuses on harvesting that ambient RF energy from mobile signals and converting it into usable electrical power for low-power electronic devices. The proposed system captures RF signals using an antenna and a copper coil when a nearby mobile phone generates high-power signals during activities such as incoming calls. The received RF signal is converted into a small DC voltage using a diode-based rectification stage. The signal is then processed using an LM358 operational amplifier configured as a comparator to detect and amplify the harvested voltage. The generated DC energy is stored temporarily in a capacitor and used to drive a low-power indicator such as an LED. This system demonstrates the feasibility of utilizing waste RF energy from mobile communication for powering ultra-low-power devices. The proposed design is simple, low-cost, and suitable for small electronic applications such as wireless sensors and monitoring systems. Although the harvested power is limited, the project highlights the potential of RF energy harvesting as an alternative supplementary energy source for future low-power electronics.      

The main Objectives of this project are:  

  To capture RF signals from nearby mobile phones using an antenna.

  To convert RF signals into DC power using a rectifier circuit.

  To process and amplify the signal using an LM358 comparator.

  To store the harvested energy using a capacitor.

  To demonstrate power generation by lighting an LED.      

The major building blocks of this project are:

1. Mobile Phone.
2. LM358 Comparator.
3. Copper coil.
4. Diode.
5. Resistor .
6. Capacitor.
7. LED.

      Block Diagram:    

video: