Spectrum Sharing Scheme Between Cellular Users And Ad-Hoc Device To Device Users In Clusters
In order to utilize spectrum resources more efficiently, protocols sharing licensed spectrum with unlicensed users are receiving increased attention. Spatial reuse is a feasible complement to existing standards. During designing interference should be considered as a major component as it is critical that licensed users maintain their expected quality of service. A distributed dynamic spectrum protocol can be used in which ad-hoc device-to-device users opportunistically access the spectrum actively in use by cellular users. The interference caused should be within the allowed interference temperature and in order to keep that interference to that allowed value the channel gain estimates are used and further they are used to set the transmit powers which is feasible for device-to-device users. Then in a random access manner network information can be distributed by using route discovery packets and it helps to establish either a single-hop or multi-hop route between two device-to-device users. The number of necessary transmissions to find a route can be reduced by adding the network information in the discovery packet. By communicating directly with each other instead of utilizing the cellular base station, power can be saved significantly. For larger networks the network is divided into clusters and communication takes place between the devices in different cluster.