Research And Implement Of D2D Route For Heterogeneous Networks

D2D(Device to Device)communication is one of important communication methods in cellular networks,with features like high quality and short link distance.D2D route technique for D2D communication in heterogeneous networks,called D2D route,is a route technique developed to suits D2D communication.Though quite many merits exist in D2D communication,using direct link in all situations is not considered wise.A proper suggestion is offered that taking the idle one as a relay device rather than regardless of it to gain a higher communication speed in some situations.D2D devices are enabled to become relays by D2D route.Route protocols that are widely used,such as AODV(Ad hoc On-demand Distance Vector),DSDV(Destination Sequence Distance Vector)and DSR(Dynamic Source Routing),are not suitable for D2D communication even though they have much features and merits.The main problem comes from their metric calculations.The references of the calculations are too limited to reflect the quality of links precisely.Meanwhile,the route protocols lack of loop-free mechanisms.When a link breaks,a new route could hardly be created,or the new route will fall into a loop in which the communication is not truly recreated.Therefore,an exclusive route for D2D communication has been designed in the thesis.The main innovation points of the thesis include the followings.Firstly,the whole routing protocol for D2D communication has been designed in the thesis,including routing-generation,routing-upgrade,routing-decision and so on.Secondly,a metric calculation based on throughput has been offered in the thesis.On Link Layer of D2D system,the calculation of the throughput has already been designed and implemented and its values are delivered to the Transmit Layer through cross-layer technique.Link quality could be reflected more precisely under the calculation.Thirdly,the whole D2D routing system has been implemented in the thesis based on software radio platform and some tests have been made on the system.The tests results show that the D2D routing based on throughput is capable of analyzing the communication environment quickly and reflecting link quality precisely which finally effectively improves the whole performance of multi-hop D2D communications.