Recycling Polluted Packet at the Physical Layer in Wireless Network Coding

We take a physical-layer perspective in detecting the falsely injected packet (pollution attack) and removing it from the polluted packet to restore the true coded packet in wireless network coding system. The proposed scheme "recycles" the polluted packet by discarding only the falsely injected packet and uses the remaining part for recovering the message. By doing so, it avoids packet re-transmission and substantially improves the bandwidth efficiency as well as the reliability of decoding.