Research On 3GPP-oriented En-Hanced 5G Indoor Positioning Techn-Ology

High-accuracy positioning is an important foundation for fully utilizing the potential of location services.The 3rd Generation Partnership Project(3GPP)has identified 5G network positioning as one of the effective solutions to provide reliable high-precision positioning,and the proposed 5G co-band positioning technology has further opened up a new direction of high-precision positioning in indoor wireless networks.This paper provides an in-depth analysis of the 5G common band positioning system for the 3 GPP protocol framework,and the main work and innovations are as follows.1)To address the lack of performance analysis of the common band positioning system in the framework of 3GPP protocol,this paper uses the 3GPP international standard as the theoretical basis,and utilizes the physical layer key technologies such as basic parameters,frame structure and resource mapping specified therein to make a more comprehensive and in-depth performance evaluation of the 5G common band positioning system.Compared with the traditional 5G in-band PRS signal,the performance of the 5G co-band positioning system is evaluated more comprehensively and deeply,including positioning measurement frequency,energy consumption,resource element consumption and positioning accuracy.First,this paper defines the localization measurement frequency based on the resource pattern of in-band PRS signals,and analyzes the relationship between localization measurement frequency and energy of the common band localization signals compared with in-band PRS;then,a resource consumption comparison model is proposed using the idea of BER equivalence to analyze the performance of common band localization signals in terms of energy consumption and resource element consumption,and explores the potential of common band positioning signals in green positioning.Finally,an expression for the positioning accuracy of the 5G common band positioning signal is derived in this paper.The simulation results show that the 5G common-band positioning signal relying on the 3GPP international standard has advantages in providing high accuracy,high continuity and low resource consumption in positioning performance.2)To address the inter-cell interference problem in the co-band system,a power allocation strategy in 5G co-band system based on Potential Game(PACB_PG)is proposed in this paper.In order to reduce the inter-cell interference of communication users in the common-band system,this paper introduces game theory into the common-band system for resource allocation algorithm design,establishes a potential game model through element mapping,designs an individual utility function based on pricing mechanism for communication users,and takes system utility maximization as the objective optimization problem.When allocating the power to communication users,the positioning performance of the positioning users in the common band system needs to be considered,so the positioning accuracy is introduced as the constraint of the objective optimization problem.After the potential game resource allocation model is established,the corresponding potential function is found to prove the existence of Nash equilibrium,and finally the KKT-based iterative water injection allocation algorithm is used to solve this Nash equilibrium and obtain the optimal solution for power allocation.The simulation results show that the PACB_PG algorithm can effectively suppress inter-cell interference in the common band system,and the average system throughput of this power allocation algorithm can reach 36.33Mbps at 50M bandwidth,which is 20.70%higher than the average allocation algorithm;the average system throughput at 20M bandwidth can reach 13.82Mbps,which is 14.78%higher than the average allocation algorithm 14.78%compared to the average distribution algorithm.The average positioning accuracy of the medium-located users under the PACB_PG algorithm is 0.11 m at 50M bandwidth,and 0.37 m at 20M bandwidth.Therefore,the proposed algorithm can improve the total throughput of the communication system and optimize the overall performance of the common band system while ensuring the sub-meter-level positioning accuracy of the common band system.3)To address the fairness problem in resource allocation of the common band system,this paper proposes a joint fairness analysis index for communication and positioning systems,uses the fairness weighting factor as a weighting for the fairness of both communication and positioning systems,and uses this joint fairness weighting method to analyze the fairness of resource allocation of the proposed PACB_PG algorithm.The simulation results show that the joint fairness index F can reach 0.8022 when the fairness weight factor a=0.5,and the PACB_PG power allocation algorithm still has good fairness when considering both communication and user positioning in the co-band system.