混合ARQ基于OFDM的系统

基于正交频分复用（OFDM）系统提出一种自适应混合自动重传请求（HARQ）方案,它充分利用发送端获得的信道状态信息对每次重传数据符号进行重组并且采用星座重组方案平均调制符号内各比特间的可靠性差异。仿真分析表明,自适应HARQ方案与星座重组方案相结合大大提高了系统通过率。     

一种采用自适应星座重组的新型HARQ方案

为了使无线通信系统中数据的传输快速可靠,需要采用自动重发请求(ARQ)和前向纠错码(FEC)相结合的混合自动重发请求(HARQ)技术。针对星座映射中比特符号产生可靠性差异,提出一种自适应星座重组的新型HARQ方案。仿真结果表明,该新型HARQ方案具有降低系统误码率和时延,提高系统性能的优点。     

OFDM系统中HARQ方案与性能仿真

研究了正交频分复用(OFDM)系统中采用的混合自动重传请求(HARQ)技术,对其性能和实现方案进行了分析;在采用高阶调制时,为均衡同一映射符号内比特可靠性差异采用星座重排方案,并对星座重排技术进行了研究;在典型城区多径信道环境下,对不采用HARQ、采用Type I HARQ、采用Type Ⅲ chase合并的HARQ和采用带有星座重排的Chase合并的HARQ4种方案的误码率和吞吐量性能分别进行了仿真;仿真结果表明,星座重排技术结合Chase合并的HARQ机制是无线通信系统中提高传输质量和吞吐量的一种高效可行的方案.     

无线传感器网络差错控制技术的能效分析

对自动请求重传(ARQ)技术和前向纠错(FEC)技术的能效进行了分析,提出在无线传感器网络中使用Chase合并混合自动请求重传(HARQ)方案实现自适应差错控制,以满足无线传感器网络的不同链路对差错控制方案的差异性要求.仿真结果表明,Chase合并HARQ为整体最优的差错控制方案.     

一种改进的不限重传次数的HARQ重传方案

为了保证数据在无线衰落信道条件下的可靠传输,产生了联合前向纠错编码(FEC)与自动请求重传(ARQ)的混合ARQ(HARQ)技术。HARQ有多种重传方案,本文针对HARQ的无限次重传方案进行了研究,提出了一种改进的基于RCPT码的HARQ重传方案,并分别与传统RCPT-HARQ方案在瑞利快衰落、慢衰落信道下进行仿真比较,仿真结果显示出改进方案在慢衰落信道条件下获得了更高的通过率。     

MIMO-OFDM系统中自适应比特交织HARQ方案

基于多天线正交频分复用(MIMO- OFDM)系统提出了一种根据信道状态信息进行自适应比特交织的混合自动重传请求(HARQ)方案,它充分利用信道的状态信息对每次重传的比特进行交织来获得频率分集增益和平均各个比特间的可靠性.仿真结果表明,在Type III HARQ类型(包括Chase合并和部分冗余递增)下,该方案可以有效降低系统的误码率性能.     

新的基于SR-SW-HARQ的低时延视频传输方案

为了实现低时延视频传输,提出了一种利用混合自动重传(HARQ)技术的解决方案.对基于H.264数据分割得到的3种对视频质量有不同贡献的数据分区,在链路层采用停止等待式自动重传(ARQ)和选择重发式自动重传相结合的协议,在物理层采用自适应的HARQ方案来进行传输.实验结果表明相对于传统的基于单数据片分割模式的视频传输方案,该方案在改善图像重建质量的基础上,有效地降低了传输时延并提高了系统的吞吐量.     

TD-LTE上行HARQ技术设计与实现

为了应对新兴无线宽带技术的竞争以及满足更高的峰值速率,3GPP提出了长期演进LTE。混合自动请求重传(HARQ)技术是保证无线通信系统高速率传输和高服务质量的关键技术之一。通过介绍TD-LTE上行HARQ过程,设计上行HARQ过程的具体实现流程并以TDD UL/DL Configuration 2为例说明自适应重传和非自适应重传的过程以及在下行信道PHICH上ACK/NACK的反馈情况。     

一种基于交织重组和星座重组的Type-II型混合ARQ方案

为提高系统的通过率及译码效率,高速可靠数据传输系统采用混合ARQ方案。本文提出了一种基于交织重组和星座重组的混合ARQ方案,分析了系统的通过率、误帧率及重传时延。通过仿真说明本方案可获得较大的通过率增益,减小重传延时,提高了系统的传输可靠性。     

一种基于交织重组和星座重组的Type-Ⅱ型混合ARQ方案

为提高系统的通过率及译码效率，高速可靠数据传输系统采用混合ARQ方案。本文提出了一种基于交织重组和星座重组的混合ARQ方案，分析了系统的通过率、误帧率及重传时延。通过仿真说明本方案可获得较大的通过率增益，减小重传延时，提高了系统的传输可靠性。     

提高卫星通信系统吞吐量的复数域网络编码算法

针对传统卫星通信系统吞吐量不高的问题,本文提出了一种基于复数域网络编码（CFNC）的卫星通信系统方案。该方案在发送前对信号进行符号级的CFNC编码,在不增加终端发射功率的情况下提供比传统卫星通信系统更高的吞吐量,并适用于多用户网络。该方案同时适用于基于处理转发器和透明转发器的卫星平台。特别是在双向卫星通信系统中,与基于伽罗瓦域网络编码（GFNC）的系统相比,本文提出的方案不仅具有更高的吞吐量而且更具有普适性。      

Health monitoring scheme‐based Forster resonance energy transfer nanocommunications in the Internet of Biological Nanothings

In this paper, a health monitoring approach for a targeted drug delivery (TDD) system taking into consideration the binding of drug to a target cell is proposed. The proposed scheme is mainly based on Forster resonance energy transfer (FRET) nanocommunications and the physical phenomenon such as protein–protein interactions in biological systems, in order to propose a molecular communication system with various forms for single and/or multiple ligand–receptor binding. Inspired by classical wireless communication system, the analysis of proposed scheme in terms of bit error rate (BER) and mutual information between the transmitter nanomachine (TN) and receiver nanomachine (RN) is presented. Subsequently, we are able to obtain a closed‐form expression for BER for the proposed scheme. The proposed scheme can be employed in the promising Internet of Biological Nanothings (IoBNT) paradigm. The numerical results reveal that the proposed scheme with multiple donors multiple acceptors system analogous to multiple input multiple output (MIMO) communication system is a superior scheme for transmission therapeutic drug information with achievable BER.     

Denoise-and-forward based adaptive diversity scheme for physical-layer network coding with multiple relay node

The capacity issue of a denoise-and-forward(DNF) protocol was focused on based PNC system of frequency non-selective Rayleigh fading channel.First,the total sum-rate of the system was derived.With the derived sum-rate expression,two policies maximizing the system sum-rate are proposed.On this basis,a novel adaptive diversity scheme was proposed.Closed-form expressions of the system outage probability with the new proposed scheme as well as the amplify-and-forward (AF) based PNC system and the conventional direct transmission were derived over frequency-nonselective Rayleigh fading channels.Simulation experiments are conducted and the results show that the outage performance of the system can be im-proved significantly compared to the AF based PNC system and the conventional direct transmission scheme.     

基于NOMA的超密集MEC网络任务卸载和资源分配方案

为了提高移动边缘计算(mobile edge computing,MEC)网络的频谱效率,满足大量用户的服务需求,建立了基于非正交多址接入(non-orthogonal multiple access,NOMA)的超密集MEC系统模型。为了解决多个用户同时卸载带来的严重通信干扰等问题,以高效利用边缘服务器资源,提出了一种联合任务卸载和资源分配的优化方案,在满足用户服务质量的前提下最小化系统总能耗。该方案联合考虑了卸载决策、功率控制、计算资源和子信道资源分配。仿真结果表明,与其他卸载方案相比,所提方案可以在满足用户服务质量的前提下有效降低系统能耗。     

Adaptive beamforming of massive MIMO based on DoA in high mobility scenarios

A direction of arrival based (DoA-based) beamforming of massive MIMO was proposed for high-speed railway scenarios.In order to guarantee that the optimal system capacity can be obtained during traveling,an iterative multi-beams scheme was proposed.It aimed to design different beams for different mobile carriage terminals (MCT) respectively.The proposal adaptively selected the number of antennas for each beam,and adaptively designed the number of beams according to system capacity.Moreover,the scheme didn’t need channel state information (CSI) that can reduce system implementation complexity and cost.Numerical results indicate that the proposed scheme is suitable for high-speed scenarios,the system performance can be improved more efficiently compared to conventional methods.     

Equation Chapter 1 Section 1基于中继的协作频谱感知性能分析及优化

提出了一种基于目标的中继协作频谱感知方案,证明了SU到SR链路上的信道条件对系统性能有较大的影响;鉴于此,提出了一种优化的最佳中继协作频谱感知(optimized BRCSS)方案,通过联合考虑目标SU到SR链路上的信道条件和 SR 到 FC 链路上的信道条件选择最佳认知中继;最后,从更实际的应用场景考虑,为了节约系统开销,进一步提出了一种自适应的最佳中继协作频谱感知方案（A-BRCSS）,即 SU 根据其信道条件,自适应地选择是否需要认知中继的协作传输。分析和仿真结果均表明,相比传统最佳中继协作频谱感知方案, Optimized BRCSS方案可以实现更高的感知性能;所提A-BRCSS方案可以实现几乎最佳的感知性能。     

极化码在LTE系统中的应用

为了实现极化码在LTE系统中的应用,提出了两类LTE系统中的极化码编码调制方案:联合极化编码调制(MLC-PCM)方案和比特交织极化编码调制(BIPCM)方案.其中,MLC-PCM方案凸显了通信系统中联合极化设计对系统性能提升的重要作用.此外,由于极化码的编码码长不一定为2的幂次,因此提出了一套简单易行且性能优异的极化码速率适配打孔方案,使得极化码的码长可以任意变化.最后,将极化编码调制方案与LTE系统Turbo码编码调制方案在所有MCS等级上进行了对比,仿真结果显示,在所有MCS等级上,极化编码调制方案都有明显性能增益.     

多载波CDMA系统中的频域线性相位内插算法

多载波CDMA系统结合了正交频分复用（OFDM）技术和CDMA技术的优点,自1993年提出以来就受到广泛的重视。本文主要讨论了载波频偏对连续OFDM符号的影响,提出了一种新的频域线性相位内插算法来估计信道响应,以对抗载波频偏对连续OFDM符号引起的相位旋转。理论分析和仿真试验都证明我们提出的算法能有效减少载波频偏对系统性能的影响。这种新算法适用于使用导频信号块状分布的多载波CDMA系统或OFDM系统。     

广东工业大学信息工程学院

广东工业大学信息工程学院成立于2000年4月，其前身为原电子与信息工程系和原机械电子工程二系的测量与控制专业。现设有“信息工程”和“测控技术与仪器”两个本科专业，拥有“电子电力与电力传动”与“测试计量技术与仪器”两个学科的硕士学位授予点。     

Efficient wireless transmission scheme based on the recent DST-MC-CDMA

The capacity of a multicarrier code-division multiple access (MC-CDMA) system is limited by a multiple access interference (MAI) from other users. In this paper, we propose a MAI cancellation scheme to transmit images over a recent discrete sine transform (DST) based MC-CDMA (DST-MC-CDMA) system. In the proposed scheme the minimum mean square error (MMSE) equalizer is used to provide the initial estimate of users’ data and the parallel interference cancellation (PIC) scheme is then used to regenerate and cancel the MAI from the desired user. The proposed scheme is called MMSE-PIC. Simulation results in multi-path fading channel confirm the excellent performance of the proposed scheme as compared to MMSE equalization method. It is also found that the best suitable tentative decision for the proposed scheme is the null zone decision or the clipper decision. We also conduct experiments to show the performance of the proposed scheme with a real image transmission over the DST-MC-CDMA system. Results show that the proposed scheme provides significant image quality improvement as compared to the existing schemes. The average peak signal to noise ratio improvement achieved by the proposed scheme over the conventional MMSE equalizer at a SNR = 30 dB is about 6.5 dB for different number of users.