Spectrum Shaping via Network Coding in Cognitive Radio Networks

TL;DR

This paper explores how network coding in cognitive radio networks acts as a spectrum shaper, enhancing spectrum availability and predictability, thereby improving secondary users' ability to detect and utilize spectrum holes efficiently.

Contribution

It introduces the concept of spectrum shaping via network coding, demonstrating its benefits for dynamic spectrum access and improved throughput for both primary and secondary users.

Findings

Network coding increases spectrum availability for secondary users.

Dynamic sensing based on spectrum shaping improves spectrum hole detection.

Both primary and secondary users achieve higher stable throughput.

Abstract

We consider a cognitive radio network where primary users (PUs) employ network coding for data transmissions. We view network coding as a spectrum shaper, in the sense that it increases spectrum availability to secondary users (SUs) and offers more structure of spectrum holes that improves the predictability of the primary spectrum. With this spectrum shaping effect of network coding, each SU can carry out adaptive channel sensing by dynamically updating the list of the PU channels predicted to be idle while giving priority to these channels when sensing. This dynamic spectrum access approach with network coding improves how SUs detect and utilize temporal spectrum holes over PU channels. Our results show that compared to the existing approaches based on retransmission, both PUs and SUs can achieve higher stable throughput, thanks to the spectrum shaping effect of network coding.