SSC-MRC混合合并接收系统在n-Rayleigh信道下的性能分析

在n-Rayleigh信道下,研究了结合切换驻留合并(SSC)与最大比合并(MRC)的混合合并接收系统的平均符号误码率(ASEP)性能。基于矩生成函数(MGF)方法,推导了SSC-MRC混合合并接收系统在n-Rayleigh衰落信道上采用相干检测的M进制相移键控(PSK)、正交幅度调制(QAM)、脉冲幅度调制(PAM)等几种数字调制方式的ASEP的精确表达式,然后对不同系统条件下的ASEP性能进行了数值仿真,结果表明:随着分集支路数的增大,衰弱因子的减小,系统的ASEP性能得到了很好的改善,验证了理论分析结果的正确性。     

TAS/SC系统的性能分析

在n-Rayleigh衰落信道下,研究了使用发射天线选择(TAS)和选择合并(SC)接收的多输入多输出(MIMO)系统的平均符号误码率(ASEP)和中断概率(OP)性能。基于矩生成函数(MGF)的方法,推导了TAS/SC系统在n-Rayleigh衰落信道上采用相移键控调制(PSK)、正交幅度调制(QAM)和脉冲幅度调制(PAM)等几种数字调制方式的ASEP的精确表达式。同时,也得到了OP的精确闭合表达式。在不同条件下对系统的ASEP和OP性能做了数值仿真,理论分析结果与仿真结果相吻合,验证了理论分析结果的正确性。     

Nakagami衰落信道上组合SC/MRC的性能分析

研究Nakagami衰落信道上组合发射机选择合并(SC)/接收机最大比合并(MRC)天线分集系统的性能.使用矩生成函数方法,推导采用组合SC/MRC天线分集和相干检测的MPSK(M进制相移键控)、MQAM(M进制正交幅度调制)、MPAM(M进制脉冲幅度调制)、BFSK(二进制频移键控)、最小相关BFSK(BFSKmin)、差分编码BPSK(DE-BPSK)和预编码MSK(最小频移键控)等几种M进制数字调制方式在Nakagami衰落信道上的误符号率性能,获得了M进制数字调制系统误符号率性能的精确数学表达式.数值计算结果阐明了发射天线和接收天线数目以及衰落参数对数字调制系统误符号率性能的影响.     

相关衰落信道上MIMO系统中组合SC/MRC的性能分析

研究相关瑞利衰落信道上MIMO系统中组合发射机选择合并(SC)/接收机最大比合并(MRC)的天线分集系统性能.使用矩生成函数方法,推导相关瑞利衰落信道上采用组合SC/MRC天线分集争相干检测的M进制相移键控(MPSK),M进制正交幅度调制(MQAM),M进制脉冲幅度调制(MPAM)等几种M进制数字调制方式的误符号率精确表达式.数值计算结果阐明相关性和天线阵结构对采用组合SC/MRC天线分集的几种M进制数字调制方式的平均误符号率性能的影响.     

非理想CSI下MIMO MRC协作通信系统的误码性能分析

协作分集和多输入多输出( MIMO)最大比合并(MRC)技术能够克服多径衰落对无线通信系统的影响和扩展覆盖范围.研究瑞利衰落信道上非理想信道状态信息下采用MIMO MRC的解码前传(DF)中继协作通信系统的误码性能.使用矩生成函数法,推导采用M进制相移键控、广义矩形M进制正交幅度调制的DF协作通信系统的平均误符号率的精...     

OFDM-MQAM在相关Nakagami-m衰落信道上的性能分析

本文研究频率选择性相关Nakagami衰落信道上采用最大比合并(MRC)分集接收的正交频分多路复用M进制正交幅度调制(OFDM-MQAM)系统.使用矩生成函数(MGF)方法和高斯超几何函数、Appell超几何函数或Lauricella函数,推导任意衰落参数频率选择性相关Nakagami衰落信道上MRC分集接收的OFDM-MQAM系统的误符号率(SER)性能,获得了OFDM-MQAM误符号率的一个新的解析表达式.数值计算结果阐明了多径路径数、Nakagami衰落参数和信道脉冲响应抽头间的相关系数对OFDM-MQAM误符号率性能的影响.     

JTRAS/OSTBC系统在Keyhole Rayleigh信道下的性能分析

在Keyhole Rayleigh衰落信道下,研究了使用联合发射/接收天线选择(JTRAS)和正交空时分组码(OST-BC)的多输入多输出(MIMO)系统的平均符号误码率(ASEP)性能.基于标量加性高斯白噪声(AWGN)信道的方法,推导出了系统在接收端信噪比的表达式.然后对不同条件下的ASEP性能做了数值仿真,验证了理论分析结果的正确性.仿真结果表明:随着发射/接收天线数的增加,JTRAS/OSTBC系统的ASEP性能得到了很好的改善.     

JTRAS/OSTBC系统在莱斯信道下的性能分析

在莱斯衰落信道下,研究了使用联合发射/接收天线选择(JTRAS)和正交空时分组码(OSTBC)的多输入多输出(MIMO)系统的平均符号误码率(ASEP)性能。基于标量加性高斯白噪声(AWGN)信道的方法,推导出了分别使用频移键控调制(FSK)和脉冲幅度调制(PAM)的ASEP性能的精确闭合表达式。数值仿真结果与理论分析结果相吻合,验证了分析结果的正确性。仿真结果表明:随着发射天线或接收天线数的增加,JTRAS/OSTBC系统的ASEP性能得到了很好的改善,当使用2FSK调制,信噪比为8 dB时,(4,4;2)系统的误码率是1×10-2,(6,6;6)系统的误码率是2×10-4;莱斯因子对JTRAS/OSTBC系统的ASEP性能有显著影响,当使用2FSK调制,信噪比为10 dB时,在莱斯因子为0时,(4,4;4)系统的误码率是7×10-4;在莱斯因子为4时,(4,4;4)系统的误码率是1.5×10-4;在莱斯因子为100时,(4,4;4)系统的误码率是8×10-5。     

MIMO衰落信道上MR-MQAM性能分析

使用矩生成函数方法分别推导了Nakagami衰落信道上多分辨率M进制正交幅度调制(MR-MQAM)的平均误比特率(BER)闭合表达式,发送和接收分别采用选择合并/最大比合并(SC/MRC)和正交空时分组编码(OSTBC).数值计算结果表明在相同的天线设置条件下,SC/MRC方案的平均误比特率性能要优于OSTBC.     

信道预测联合收发分集的正交信号误码性能

为解决采用最小均方误差(MMSE)信道预测的发射天线选择(TASP)/接收天线最大比合并(MRC)的无线通信系统设计问题,利用抛物柱面函数以及高斯Q函数的近似表达式和矩生成函数(MGF)法,分别推导了瑞利块衰落信道上采用TASP/MRC天线分集的相干检测M进制正交和双正交信号的平均误符号率(ASER)精确表达式以及正交信号ASER的近似表达式.数值计算和仿真结果验证了采用TASP/MRC和相干检测的正交/双正交ASER精确表达式的正确性以及正交信号ASER近似表达式的准确性.上述M进制正交/双正交信号ASER精确或近似表达式,可用于设计采用相干检测M进制正交和双正交信号的TASP/MRC天线分集系统,并能够快速地确定收发天线数和信道预测器级数等参数,避免耗时的计算机仿真.     

Performance of asynchronous slow frequency-hop multiple-accessnetworks with MFSK modulation

The performance of asynchronous slow frequency-hop spread-spectrum multiple-access networks where each user transmits L, M-ary symbols per hop using M-ary frequency-shift keying (FSK) modulation with noncoherent demodulation is investigated. Expressions for the decision variables are derived for a given multiple FSK (MFSK) symbol within a hop hit by K' interfering users under additive white Gaussian noise and Rayleigh fading channel models. For the special case when M=2, an accurate analytic approximation for the average error probability is derived as a function of L and K' and semianalytic Monte Carlo simulations are performed to estimate the probability of error for M larger than 2. The results are used to investigate the dependence of the average symbol error probability on L and M. Finally, the effect of enforcing phase transition between the MFSK symbols within a hop is investigated     

Performance Analysis of the Double-Antenna SDC System Over <Emphasis Type="Italic">N</Emphasis>-Nakagami Fading Channels

The performance of the double-antenna switched diversity combining (SDC) system over N-Nakagami fading channels is investigated in this paper. Based on the method of the probability density function of the signal-to-noise ratio, the exact expressions for the channel capacity and average symbol error probability (ASEP) are derived. Then the channel capacity and ASEP performance under different conditions is evaluated through numerical simulations to verify the analysis. The simulation results showed that the performance of the double-antenna SDC system is improved with the fading coefficient increased, but the level of improvement is declined as the number of cascaded components increased.     

A new closed-form of ASEP and channel capacity with MRC and selection combining over Inverse Gaussian shadowing

This paper analyse and investigate the performance of communication system with maximal ratio combining (MRC) and selection combining (SC) over Inverse Gaussian (IG) fading distribution. All formats of coherent and non-coherent modulation schemes are considered and novel analytical expressions of average symbol error probability (ASEP) with diversity are derived. Gamma and IG fading distributions are popularly used as a mathematically less complex solution to lognormal in the open literature. Hence, we provide a comparative analysis between IG and gamma fading with the aim to provide a quantitative measure of the difference between the two distributions in the context of ASEP. Moreover, the novel closed-form expressions of channel capacity under transmission schemes such as optimal rate adaptation (ORA) and channel inversion fixed rate (CIFR) are derived and analysed with MRC and SC diversity over IG fading. The analytical results have been validated with the Monte Carlo simulations and the exact numerical results.     

Performance analysis of shadowed-Rice fading channel with cooperative spectrum sensing

In this paper, the performance analysis of wireless communication system over shadowed-Rice (SR) composite fading channel has been investigated and analysed. The unified analytical expressions of the average symbol error probability (ASEP) for several coherent and non-coherent modulation schemes separately with different constellation sizes are derived for composite fading channel under two different fade mitigation methods, with maximal ratio combining (MRC) microdiversity (Method 1) and MRC applied over the composite fading channel (Method 2). Furthermore, an asymptotic analysis is carried out and a closed-form expression of the ASEP with Method 2 is presented. Analytical expressions of the corresponding average probability of energy detection (PD) are formulated for both the methods. Finally, the derived PD expression is utilised to analyse the performance of cooperative system assuming erroneous feedback channel. Analysis of optimisation of detection threshold as well as number of cognitive users to minimise the total error rate is also carried out. The closed-form expressions are validated by comparing them with exact numerical results and Monte Carlo simulation.     

New Analytical Expressions for ASEP of Modulation Techniques with Diversity Over Lognormal Fading Channels with Application to Interference-Limited Environment

In this paper, the analytical expressions of the average symbol error probability (ASEP) for both coherent and non-coherent modulation formats with diversity schemes such as maximal ratio combining (MRC), equal-gain combining (EGC), and selection combining (SC) over the lognormal (LN) distribution assuming independent and identically distributed (i.i.d.) channels have been derived. The functions involving LN distribution are simplified using the Gauss–Hermit and Gaussian Quadrature integration. Furthermore, the effect of the diversity order and constellation size on the error probability has been examined extensively under various shadowing conditions such as infrequent light, average, and frequent heavy shadowing. As an application, the derived results are used to analyze the performance of the communication systems over the interference-limited environment. The impact of the number of interferers on important performance metrics such as the outage probability, the ASEP, and the channel capacity has been examined. The accuracy of the analytical results are validated by comparing them with the exact numerical results and Monte Carlo simulations. The analytical expressions are simple and easily implementable in software package such as MATLAB. The proposed analytical expressions are supposed to be a vital tool in areas such as IEEE 802.15.3a wireless communication system, indoor environment, radio channel effect by body worn devices, ultra-wideband indoor channel.     

Equal-gain and maximal-ratio combining over nonidentical Weibull fading channels

We study the performance of L-branch equal-gain combining (EGC) and maximal-ratio combining (MRC) receivers operating over nonidentical Weibull-fading channels. Closed-form expressions are derived for the moments of the signal-to-noise ratio (SNR) at the output of the combiner and significant performance criteria, for both independent and correlative fading, such as average output SNR, amount of fading and spectral efficiency at the low power regime, are studied. We also evaluate the outage and the average symbol error probability (ASEP) for several coherent and noncoherent modulation schemes, using a closed-form expression for the moment-generating function (mgf) of the output SNR for MRC receivers and the Pade/spl acute/ approximation to the mgf for EGC receivers. The ASEP of dual-branch EGC and MRC receivers is also obtained in correlative fading. The proposed mathematical analysis is complimented by various numerical results, which point out the effects of fading severity and correlation on the overall system performance. Computer simulations are also performed to verify the validity and the accuracy of the proposed theoretical approach.     

Reduced state sequence detection of full response continuous phase modulation

A reduced state sequence detector (RSSD) which combines decision feedback with Viterbi decoding is proposed for M-ary full response continuous phase modulation. The detector is analysed with minimum Euclidean distances and by simulations of the symbol error probability. It is shown that M-ary full response CPM schemes can be optimally decoded by a decoder with only two states when the modulation index is relatively small (>     

Exact performance analysis of M-ary QAM with MRC diversity in Rician fading channels

The exact expression of symbol error rate (SER) is derived for coherent square M-ary quadrature amplitude modulation (M-QAM) using Lth order maximal-ratio combining (MRC) diversity in Rician fading channels with an arbitrary fading parameter. The accuracy of the SER estimates evaluated by this expression is verified through comparison with the results evaluated by numerical integration.