LTE Advanced

About: LTE Advanced is a research topic. Over the lifetime, 4055 publications have been published within this topic receiving 74262 citations. The topic is also known as: Long-Term Evolution Advanced & LTE-A.

Device-to-device resource allocation in LTE-advanced networks by hybrid particle swarm optimization and genetic algorithm

Abstract: D2D (Device-to-Device) communication is one of the promising technologies in the LTE (Long Term Evolution)-Advanced communication network. From system perspective, this technology can increase frequency efficiency of the whole macro cell. From user perspective, however, a D2D pair which shares the same frequency resource of CUE (Cellular User Equipment) can cause interference with the CUE in the downlink. Thus, reducing interference for the cellular users and allocating frequency resource for the D2D pairs are important in D2D communication. In this paper, two resource allocation schemes which are based on PSO (Particle Swarm Optimization) and hybrid PSO-GA (Genetic Algorithm) are proposed to maximize the system throughput by allowing up to two D2D pairs to share the same frequency resource with one CUE. Moreover, a scheme has been considered to mitigate the interference caused to CUEs. The simulation results show that service of CUEs and system performance can be effectively guaranteed by using the proposed schemes.

Reference Signal Design for Flexible MIMO Operation in LTE-Advanced Downlink

Abstract: In this paper we address the issue of demodulation reference signal design for LTE-Advanced downlink. Practical systems such as LTE-Advanced should operate in highly time-frequency selective environment. Hence, they impose a very tight trade-off between the radio resources available for reference signals used for channel estimation and spectral efficiency targets to be met. As an additional constraint, LTE-Advanced brings to real deployments state-of-the-art multi-antenna technologies such as multi-user MIMO and cooperative MIMO. The difficult radio environment and the multitude of different multi-antenna techniques set very high challenges to the reference signal design. In this paper we discuss selected issues of realistic demodulation reference signal design for LTE-Advanced. We highlight the trade-offs that are needed for enabling advanced MIMO technologies, while at the same time allowing low complexity channel estimation at the receiver side without increasing related signaling overhead. Based on the analysis we propose a certain reference signal design for LTE-Advanced that fulfills all the required design criteria.

Energy-efficient and interference-aware handover decision for the LTE-Advanced femtocell network

Abstract: Femtocells will play a key role for the wide adoption of the LTE-Advanced system, as they bring the access network closer to the end user in a cost-effective manner. This disruptive communication paradigm, however, dictates the use of advanced interference and mobility management algorithms to cope with the dense yet unplanned network layout. In this paper, we present an interference-aware handover decision algorithm for the LTE-Advanced femtocell network, which utilizes standard signal measurements to select the candidate cell that a) attains the minimum required channel gain for sustaining service continuity and b) minimizes the mean UE transmit power for a prescribed mean SINR target. The proposed algorithm attains backwards compatibility with the LTE-Advanced system, as it is deployed by using the private mechanism for non-standard use. Based on the evaluation methodology of the Small Cell forum, we validate the performance of the proposed algorithm and compare it against that of other state-of-the-art algorithms.

Requirement of Handover Modeling in the Downlink 3GPP Long Term Evolution System

Abstract: Long Term Evolution (LTE) is the next generation wireless system that uses Break-before-Connect technology in the handover scheme, unlike handover in the Wide-band Code Division Multiple Access (WCDMA) that uses Connect-before-Break technology. In the LTE system, handover is one of the important radio resource management schemes that are responsible for mobility of user equipments, load balancing and interference management. This paper provides detailed description on requirements involved for handover procedure in the LTE system and the feasibility to extend the current software simulation tool of the LTE system to support multiple cells for handover. This paper contributes to the identification of the requirements and specifications that are needed for further study of handover procedure in the LTE system.

Group-Sparse-Based Joint Power and Resource Block Allocation Design of Hybrid Device-to-Device and LTE-Advanced Networks

Abstract: In this paper, a joint power and resource block (RB) allocation (JPRBA) algorithm with low complexity is proposed, which addresses the intra-and-inter-cell interference management problem for a multicell device-to-device (D2D) communication underlaying LTE-Advanced network. We first introduce a power control and resource allocation vector (PORAVdm) to each D2D transmitter, and the set of all PORAVdm has two functions: one is to select appropriate reused RBs for each D2D link, whereas the other is to determine the optimal power for D2D transmitters on each selected RB. To obtain the appropriate PORAVdms, we exploit the group sparse structure to formulate a sum rate maximization problem (referred to as the group least absolute shrinkage and selection operator programming). Then we derive the stationary solution by solving its equivalent sparse weighted mean square error minimization problem. Finally, simulation results show that the proposed JPRBA algorithm can efficiently improve the total throughput.