Wireless Networks Should Spread Spectrum Based on Demands

Today’s local-area, mesh and cellular networks assign a single narrow-band channel to a node, and this assignment remains fixed over long time scales. Using network traces, we show that the load within a network can vary significantly even over short time scales on the order of tens of seconds. Therefore, we make the case for allocating spectrum ondemand to nodes and regions of the network that need it. We present an architecture that shares the entire spectrum on-demand using spread-spectrum codes. If implemented, the system will achieve fine-grained spectrum allocation for bursty traffic without requiring inter-cell coordination. Preliminary experiments suggest a throughput improvement of 75% over commodity 802.11b networks. By eschewing the notion of channelization, and matching demand bursts with spectrum dynamically, better wireless networks that sustain higher throughputs may be designed.