Embracing wireless interference

TLDR

Interference is traditionally viewed as harmful, and wireless networks aim to avoid simultaneous transmissions to prevent it. The study proposes intentionally allowing selected senders to interfere by having routers forward signals instead of packets. Routers forward interfering signals, and destinations use network‑level information to cancel interference and recover intended signals, implemented with software radios. The approach produces analog network coding, theoretically doubles capacity in a 2‑way relay network, and experimentally achieves higher throughput than conventional routing and prior network‑coding methods.

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 mixes signals not bits. So, what if wireless routers forward signals instead of packets? Theoretically, such an approach doubles the capacity of the canonical 2-way relay network. Surprisingly, it is also practical. We implement our design using software radios and show that it achieves significantly higher throughput than both traditional wireless routing and prior work on wireless network coding.