Studies On Vehicle Broadcast Communication Resource Allocation Algorithm Based On LTE-V

As one of the key technologies of intelligent traffic,vehicle to vehicle(V2V)communication can mitigate the burden of base station.In addition,the broadcast transmission of safety messages is one of the related research contents of vehicle network.It has higher requirements for the reliability and delay of data transmission.Reasonable resource allocation is the key to improve the reliability of data transmission.Different communication standardization organizations have proposed their own protocol architectures for the vehicle networks.Therefore,the LTE-V technology is presented based on the Third Generation Partnership Project(3GPP)in this thesis.We design two types of resource allocation algorithms for V2 V broadcast communicationm in different traffic densities.The main difference between this two algorithms is whether the resource allocation of all V2 V users is scheduled by the base station.The research contents are as follows:1.A kind of V2 V autonomous resource selection algorithm based on SA decoding is studied for V2 V broadcast communication distributed resource scheduling algorithms under non-dense traffic environment,which is less concerned with the reliability of hidden terminals and scheduling allocation(Scheduling Allocation,SA)information transmission.In this algorithm,the vehicle obtains the reserved resources of SA and packets of two jump neighbor vehicles through the information integration mechanism,and selects the transmission resource from the unreserved resources to reduce the interference caused by the hidden terminal,and increases the reliability of SA and packet transmission.In addition,a resource pooling is used to decrease the reselection of resources due to consolidation conflicts,thereby further improving the reliability of packet transmission.The simulate results show that this algorithm has been improved in packet reception rate and updating delay compared with those algorithms which do not consider the reliability of hidden terminals and SA data transmission.2.In order to solve the problem of packet loss caused by cumulative interference and semi-duplex constraints in the existing centralized resource scheduling algorithms for V2 V broadcast communication in dense traffic environment,we propose an iterative coloring resource allocation algorithm based on bi-directional interference graph.The algorithm establishes a system model of V2 V broadcast communication with the goal of maximizing the number of transmitted packets successfully,simplifies the complex distance relationship among broadcast groups reasonably,and constructs a bidirectional interference graph based on the different interference degree among users.Furthermore,we consider the problem of packet loss caused by half-duplex constraints using the theory of dual coloring to improve the interference graph.In addition,according to the degree of interference of each node,iterative coloring allocates resources to nodes with severe interference preferentially,thereby reducing the impact of cumulative interference,and controlling the interference between V2 V communications within a reasonable range.The simulation results show that the algorithm can further improve packet reception rate and decrease the update delay.