Highly sensitive FM frequency scavenger integrated in building materials

Due to the abundance of ambient RF (Radio Frequency) energy, considerable research effort has been invested in RF energy scavenging. In this paper, we propose a rectifier which can be embedded into the building materials to provide a sustainable energy source in urban environments. The power will be available through DC sockets with different voltage settings. A highly sensitive and efficient rectifier operating at the FM frequency band is proposed which exhibits favorable impedance matching over a broad low input power range of -50 to -20 dBm (0.01 to 10 μW). Measurement results of input reflection coefficient and rectified output power are provided. An output DC power of around 11 μW is achieved from concurrently rectifying six tones of -20 dBm, providing a viable perpetual energy source for low power applications.