Dynamic Channel Bonding: Enabling Flexible Spectrum Aggregation
Pei Huang, Xi Yang, Li Xiao · IEEE Transactions on Mobile Computing · 2016
To support applications that demand high-speed wireless communication, the fifth generation (5G) Wi-Fi increases the channel bonding from 40 MHz in 802.11n to 80, and even 160 MHz under certain conditions in 802.11ac. However, inefficiency and unfairness issues arise when devices that use different channel widths coexist in a contention domain. In this paper, we propose a dynamic channel bonding (DyB) protocol in which a node is allowed to start a transmission as long as there are some idle narrow channels and it gradually increases the channel width during transmission whenever new narrow channels become available. To enable communication over uncertain channels, a convolution method is introduced to achieve fast spectrum agreement between the transmitter and the receiver. In addition, DyB considers the severe contention in a wide band of spectrum. A compound preamble is designed to make collisions detectable in the frequency domain and a parallel bitwise arbitration is designed to quickly resolve the collisions in the time domain. We implement and evaluate the DyB through both the GNU Radio/USRP platform and ns-2 simulations. Experimental results and simulations show that DyB well addresses the inefficiency and unfairness issues caused by heterogeneous radio coexistence.