Spectrum- and energy-efficient D2DWRAN

IEEE 802.22 is the first world-wide standard for wireless regional area networks using cognitive radio technologies. Major drawbacks of these networks are limited network capacity and low energy efficiency. One potential solution for these drawbacks is device-to-device communication, which can be incorporated as D2DWRAN. D2DWRAN features direct intracell communication, reuse of channels, and use of multiple operating channels. In this article, we mainly discuss energy-efficient spectrum sharing in D2DWRAN. We explicate a mechanism to increase energy efficiency for long distance links using relays. Along with energy, channel utilization and fairness are also considered while choosing relays. Thus, significant improvement in both network capacity and energy efficiency can be achieved. The schemes discussed here can also be used in other D2D communication settings.