A Collaborative Spectrum-Sharing Framework for LTE Virtualization

Wireless virtualization has significant potential for improving the efficiency of resource utilization through spectrum sharing. However, several challenges exist in en- abling/implementing virtualization over the current static cellu- lar infrastructure. In the meantime, virtualization necessitates spectrum sharing and a collaborative network management entity that needs to provide efficient isolation strategies that protects multiple operators from suffering interference in shared frequency bands. Toward enabling virtualization, we develop a framework based on 3GPP LTE, in which spectrum is reused temporally and spatially by more than one operator. The usage of spectrum is adjusted by network parameters and network parameters are configured based on power and radio propagation characteristics. In the framework, we minimally modify the radio resource manager (RRM) of LTE into a virtual resource manager. Further, the popular LTE enhanced inter- cell interference cancellation (eICIC) - time domain muting is adopted/modified as an isolation technique in a virtual setting. Extensive simulations are conducted that show the possibility of virtualization to enable every operator to obtain a higher throughput in an LTE network compared to operators working separately. However, the network configuration driven by trade- offs will have to be carefully considered to ensure isolation. In summary, a collaborative approach by multiple operators to share spectrum can be of mutual benefit