This paper derives an approximate formula for probability density function(PDF) of received signal-to-interference-and-noise ratio(SINR) at user terminal when matched filter(MF) is adopted at a base station(BS).This d...This paper derives an approximate formula for probability density function(PDF) of received signal-to-interference-and-noise ratio(SINR) at user terminal when matched filter(MF) is adopted at a base station(BS).This distribution of SINR can be used to make an analysis of average sum-rate,outage probability,and symbol error rate of massive MIMO downlink with MF at BS.From simulation,it is found that the derived approximate analytical expression for PDF of SINR is consistent with the simulated exact PDF from the definition of SINR in medium-scale and large-scale MIMO systems.展开更多
针对先进的长期演进(long term evolution advanced,LTE-A)系统中跨载波聚合技术下的频谱效率问题,考虑到载波衰减特性不同,研究发现,过多的控制开销限制了低频分量载波良好的数据承载能力,为此,提出基于信干噪比(signal to interferenc...针对先进的长期演进(long term evolution advanced,LTE-A)系统中跨载波聚合技术下的频谱效率问题,考虑到载波衰减特性不同,研究发现,过多的控制开销限制了低频分量载波良好的数据承载能力,为此,提出基于信干噪比(signal to interference plus noise ratio,SINR)的分量载波分配方案。该方案根据控制信息能否被正确解调将用户进行分组,然后针对不同分组的用户分配不同的主分量载波,从而减少低频分量载波承载的控制信息开销,提高频谱效率。仿真结果表明,改进的分配方案有效地提高了小区总吞吐量。展开更多
在给出LTE(Long Term Evolution)下行多天线传输系统模型的基础上,通过理论分析得出了各多天线模式下用户接收信号信噪比(SINR)的计算公式,提出了含预编码的多用户MIMO(MU-MIMO-Pre)的调度算法。通过系统级仿真得到了不同多天线模式(包...在给出LTE(Long Term Evolution)下行多天线传输系统模型的基础上,通过理论分析得出了各多天线模式下用户接收信号信噪比(SINR)的计算公式,提出了含预编码的多用户MIMO(MU-MIMO-Pre)的调度算法。通过系统级仿真得到了不同多天线模式(包括其对应调度算法)以及不同站距下的吞吐量结果和用户公平性曲线,并对各种多天线模式的优缺点进行分析和比较。展开更多
The coverage probability of both the cellular users and the Device-to-Device(D2D) users are analyzed. We assume that the cellular users are able to communication with the Base Station(BS) either by relying on the assi...The coverage probability of both the cellular users and the Device-to-Device(D2D) users are analyzed. We assume that the cellular users are able to communication with the Base Station(BS) either by relying on the assistance of Full-Duplex(FD) mode relays or via direct user-to-BS links with high-enough Signal-to-Interference-plus-Noise-Ratio(SINR). Note that the FD-mode devices are capable of simultaneously operating in two modes,i.e. the D2D mode and the cooperative relay mode,with the sum power consumption at these devices kept constant. The closedform expressions for coverage probability of both tier users are derived. After that,numerical analyses are provided,showing that the coverage probability of the both the cellular and the D2D users can be substantially influenced by a variety of parameters,including the power allocation factor of the relays,the density of users,and the self-interference imposed on the FD mode relays,etc. Furthermore,in the D2D enabled networks,it is shown that the FD relay aided transmission is beneficial to enhancing the coverage probability of the cellular users if the target SINR is lower than 5 d B.展开更多
In CSMA/CN, whenever inferring that a receiving frame gets corrupted, the receiver sends back its signature as a collision notification(CN) to the sender. Upon detecting an arrival of the CN, the sender will abort the...In CSMA/CN, whenever inferring that a receiving frame gets corrupted, the receiver sends back its signature as a collision notification(CN) to the sender. Upon detecting an arrival of the CN, the sender will abort the ongoing transmission immediately. However, in low signal-to-interference-plus-noise ratio(SINR), the false alarm of the CN occurs frequently, which might force a sender not to transmit any frame at all. To overcome this drawback, this paper proposes CSMA/CN+ to enhance the performance of CSMA/CN. In CSMA/CN+, we introduce an additional signature. The receiver, adapting to channel conditions and self-signal suppression capability, prudently determines whether to send back zero, one, or two signatures to the sender. In this way, we can reduce or exclude false alarms and therefore improve the system performance. In this paper, we first present the design of CSMA/CN+. We then apply the design in a wireless LAN, and theoretically analyze the detection performance of the notification and the system throughput. Extensive simulations verify that CSMA/CN+ can remarkably improve the system throughput of CSMA/CN and our analysis is very accurate.展开更多
The full-duplex(FD) based wireless communication devices,which are capable of concurrently transmitting and receiving signals with a single frequency band,suffer from a severe self-interference(SI) due to the large po...The full-duplex(FD) based wireless communication devices,which are capable of concurrently transmitting and receiving signals with a single frequency band,suffer from a severe self-interference(SI) due to the large power difference between the devices' own transmission and the useful signal comes from the remote transmitters. To enable the practical FD devices to be implementable,the SI power must be sufficiently suppressed to the level of background noise power,making the received signal-to-interference-plus-noise ratio(SINR) satisfy the decoding requirement. In this paper,the design and implementation of the duplexer for facilitating SI cancellation in FD based wireless communications are investigated,with a new type of duplexer(i.e. an improved directional coupler) designed for improving the spatial suppression of the SI power. Furthermore,the practical circuit boards are designed and verified for the proposed prototype,showing that the spatial suppression capability may be up to 36 d B(i.e. much higher than that attainable in the commonly designed ferrite circulator) by using the proposed design.展开更多
基金Supported by the National Natural Science Foundation of China(No.61271230,61301107)the Fundamental Research Funds for the Central Universities(No.30920130122004)Open Research Fund of National Mobile Communications Research Laboratory,Southeast University(No.2013D02)
文摘This paper derives an approximate formula for probability density function(PDF) of received signal-to-interference-and-noise ratio(SINR) at user terminal when matched filter(MF) is adopted at a base station(BS).This distribution of SINR can be used to make an analysis of average sum-rate,outage probability,and symbol error rate of massive MIMO downlink with MF at BS.From simulation,it is found that the derived approximate analytical expression for PDF of SINR is consistent with the simulated exact PDF from the definition of SINR in medium-scale and large-scale MIMO systems.
文摘针对先进的长期演进(long term evolution advanced,LTE-A)系统中跨载波聚合技术下的频谱效率问题,考虑到载波衰减特性不同,研究发现,过多的控制开销限制了低频分量载波良好的数据承载能力,为此,提出基于信干噪比(signal to interference plus noise ratio,SINR)的分量载波分配方案。该方案根据控制信息能否被正确解调将用户进行分组,然后针对不同分组的用户分配不同的主分量载波,从而减少低频分量载波承载的控制信息开销,提高频谱效率。仿真结果表明,改进的分配方案有效地提高了小区总吞吐量。
文摘在给出LTE(Long Term Evolution)下行多天线传输系统模型的基础上,通过理论分析得出了各多天线模式下用户接收信号信噪比(SINR)的计算公式,提出了含预编码的多用户MIMO(MU-MIMO-Pre)的调度算法。通过系统级仿真得到了不同多天线模式(包括其对应调度算法)以及不同站距下的吞吐量结果和用户公平性曲线,并对各种多天线模式的优缺点进行分析和比较。
文摘为了提高先进的长期演进(LTE-advanced,LTE-A)移动通信系统的传输效率,研究了提高子带的信干噪比(signal interference ratio,SINR)估计精度的问题,提出了一种利用参考信号(reference signal,RS)的信号均衡估计SINR的算法,该算法通过本地RS和均衡后的RS的方差计算SINR,与直接利用最小二乘法(least square,LS)计算参考信号接收功率(reference signal received power,RSRP)和干扰噪声(noise)得到SINR的传统算法相比,在增加有限复杂度情况下,SINR的估计精度有明显提高,特别是在终端处于高速移动、多普勒效应比较明显的信道环境下,SINR估算性能提升更加明显,从而提高系统的传输效率。
基金supported by Key Project of the National Natural Science Foundation of China (Grant No.61431001)National Natural Science Foundation of China (Grant Nos.61501182,U1501253,61377024)+3 种基金Research Foundation of Education Department of Hunan Province (Grant No.15C0558)Startup Foundation for Doctors of Hunan University of Science and Technology (Grant No.E51539)Key Laboratory of Cognitive Radio and Information Processing,Ministry of Education (Guilin University of Electronic Technology)Foundation of Beijing Engineering and Technology Center for Convergence Networks and Ubiquitous Services
文摘The coverage probability of both the cellular users and the Device-to-Device(D2D) users are analyzed. We assume that the cellular users are able to communication with the Base Station(BS) either by relying on the assistance of Full-Duplex(FD) mode relays or via direct user-to-BS links with high-enough Signal-to-Interference-plus-Noise-Ratio(SINR). Note that the FD-mode devices are capable of simultaneously operating in two modes,i.e. the D2D mode and the cooperative relay mode,with the sum power consumption at these devices kept constant. The closedform expressions for coverage probability of both tier users are derived. After that,numerical analyses are provided,showing that the coverage probability of the both the cellular and the D2D users can be substantially influenced by a variety of parameters,including the power allocation factor of the relays,the density of users,and the self-interference imposed on the FD mode relays,etc. Furthermore,in the D2D enabled networks,it is shown that the FD relay aided transmission is beneficial to enhancing the coverage probability of the cellular users if the target SINR is lower than 5 d B.
基金supported by the Macao FDCTMOST grant 001/2015/AMJMacao FDCT grants 056/2017/A2 and 005/2016/A1
文摘In CSMA/CN, whenever inferring that a receiving frame gets corrupted, the receiver sends back its signature as a collision notification(CN) to the sender. Upon detecting an arrival of the CN, the sender will abort the ongoing transmission immediately. However, in low signal-to-interference-plus-noise ratio(SINR), the false alarm of the CN occurs frequently, which might force a sender not to transmit any frame at all. To overcome this drawback, this paper proposes CSMA/CN+ to enhance the performance of CSMA/CN. In CSMA/CN+, we introduce an additional signature. The receiver, adapting to channel conditions and self-signal suppression capability, prudently determines whether to send back zero, one, or two signatures to the sender. In this way, we can reduce or exclude false alarms and therefore improve the system performance. In this paper, we first present the design of CSMA/CN+. We then apply the design in a wireless LAN, and theoretically analyze the detection performance of the notification and the system throughput. Extensive simulations verify that CSMA/CN+ can remarkably improve the system throughput of CSMA/CN and our analysis is very accurate.
基金supported by the key project of the National Natural Science Foundation of China(No.61431001)the 5G research program of China Mobile Research Institute (No.[2015] 0615)+1 种基金Key Laboratory of Cognitive Radio and Information Processing,Ministry of Education(Guilin University of Electronic Technology)the Foundation of Beijing Engineering and Technology Center for Convergence Networks and Ubiquitous Services
文摘The full-duplex(FD) based wireless communication devices,which are capable of concurrently transmitting and receiving signals with a single frequency band,suffer from a severe self-interference(SI) due to the large power difference between the devices' own transmission and the useful signal comes from the remote transmitters. To enable the practical FD devices to be implementable,the SI power must be sufficiently suppressed to the level of background noise power,making the received signal-to-interference-plus-noise ratio(SINR) satisfy the decoding requirement. In this paper,the design and implementation of the duplexer for facilitating SI cancellation in FD based wireless communications are investigated,with a new type of duplexer(i.e. an improved directional coupler) designed for improving the spatial suppression of the SI power. Furthermore,the practical circuit boards are designed and verified for the proposed prototype,showing that the spatial suppression capability may be up to 36 d B(i.e. much higher than that attainable in the commonly designed ferrite circulator) by using the proposed design.
