PX505 Innovation Project

Backscattering Using Classical MCU

Students

• Anton Dumas

• Alexandre De Carlo

• Arnaud Voisin

• Bastien Lemaire

Subject

Backscattering Communications Using Classical Micro-Controller is a project based on the compelling idea proposed by where a transmission can be done without using any RF chip. By modifying the internal state of GPIOs connected to an antenna, it is possible to modulate the backscattered signal of a remote reader. This technique allows to reduce the number of component of the system and decrease the power consumption.

This modulated power can be linked to the delta RCS $\sigma _{d}$ introduced in which allows to extract read range of the system.

Results

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  Fig. 1: S11 measured at the VNA for different GPIO modes of a PIC16.

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  Fig. 2: $|\rho |^{2}$ for a dipole antenna in the 2 different states.

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  Fig. 3: Polar representation of $\rho$ in the 2 different states.

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  Fig. 4: Delta RCS as a function of the frequency.

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  Fig. 5: Read range as a function of the frequency.

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  Fig. 6: Modulated signal observed at the spectrum analyzer.