Embracing Wireless Interference: Analog Network Coding

Abstract

Traditionally, interference is considered harmful.Wireless networks strive to avoid scheduling multiple transmissions at the same time in order to prevent interference. This paper adopts the opposite approach; it encourages strategically picked senders to interfere. Instead of forwarding packets,routers forward the interfering signals. The destination leverages network-level information to cancel the interference and recover the signal destined to it. The result is analog network coding because it codes signals not bits. So, what if wireless routers forward signals instead of packets? Theoretically, we prove that such an approach doubles the capacity of the canonical relay network. Surprisingly, it is also practical. We implement our design using softwareradios and show that it achieves significantly higher throughput than both traditional wireless routing and prior work on wireless network coding.