ABSTRACT

Over recent epoch, initial uplink synchronization has become an essential part of the wireless communication systems owing to its amenities in the identification of new users to originate communication. Yet, allocating and sharing resources to users is a bottleneck due to the interference caused by multiple users. Besides, preceding works didn't concentrate on the usage of an effective mechanism to estimate the parameters of the received signal in the multiuser synchronization environment. These downsides affect the throughput and spectrum efficiency of the designed OFDMA system. To address these bottlenecks, this paper proposes the Joint Initial Uplink Synchronization and Interference Aware Resource Allocation (JIUS-IRA) in the Multi-User OFDMA system. JIUS-IRA comprises four processes: Parameter Estimation, Optimum Antenna Selection, Resource Allocation, and Resource Sharing. Initially, JIUS-IRA executes the Fast Block Least Mean Square-based Parameters Estimation Scheme (FBLMS-PES) to estimate the user parameters. To reduce the power consumption during transmission between 5G MIMO base station and users, JIUS-IRA selects the optimal antenna for transmission. The Sign Rank Oriented Resource Allocation (SO-RA) method is executed to allocate sub-channel resources to the cellular user. The resource requirement of D2D users present in the OFDMA system is resolved via the Harris Hawks Optimizer based Resource Sharing Scheme (H2ORSS). The numerical results acquired from the simulation are highly confidential with regard to metrics Root Mean Square Error (RMSE) of timing estimation (∼0.006), RMSE of power estimation (∼0.0079), RMSE of frequency estimation (∼ 0.008), Throughput (∼95%), Spectrum Efficiency (∼11.9 bps), and Complexity (0.045 × 10⁴).

摘要

在最近的时代，初始上行链路同步由于其在识别新用户以发起通信方面的便利性而已成为无线通信系统的重要组成部分。然而，由于多个用户造成的干扰，为用户分配和共享资源是一个瓶颈。此外，先前的工作并没有集中于使用有效的机制来估计多用户同步环境中接收信号的参数。这些缺点会影响所设计的 OFDMA 系统的吞吐量和频谱效率。为了解决这些瓶颈，本文提出了多用户 OFDMA 系统中的联合初始上行同步和干扰感知资源分配（JIUS-IRA）。JIUS-IRA 包括四个过程：参数估计、最优天线选择、资源分配和资源共享。最初，JIUS-IRA 执行基于快速块最小均方的参数估计方案（FBLMS-PES）来估计用户参数。为了降低5G MIMO基站和用户之间传输过程中的功耗，JIUS-IRA选择最优的天线进行传输。执行面向符号等级的资源分配(SO-RA)方法来向蜂窝用户分配子信道资源。OFDMA 系统中存在的 D2D 用户的资源需求通过基于 Harris Hawks 优化器的资源共享方案 (H2ORSS) 来解决。从仿真中获得的数值结果对于时序估计的均方根误差 (RMSE) (∼0.006)、功率​​估计的 RMSE (∼0.0079)、频率估计的 RMSE (∼ 0.008) 等指标是高度机密的，⁴ ).