共查询到18条相似文献,搜索用时 62 毫秒
1.
2.
3.
4.
当发射天线数大于2时,复信号空时分组码不能实现满速率编码,可以通过星座旋转来设计发送矩阵,使系统同时获得满分集增益和最大的编码速率。通过对传统的旋转星座准正交空时分组码加以改进,使每根天线在不同时隙发射的信号属于不同星座,在保证满分集和最大的编码速率的同时,减小了码间干扰,更有利于译码器译码,提高了系统性能。 相似文献
5.
基于典型的多输入-多输出无线通信系统,研究了一种适用于任意发射天线数的高速率复正交空时分组码设计方法。证明了采用该算法所设计的复正交空时分组码能达到满发送分集度和未对信号进行线性处理时的最大码率(m+1)/2m(m为自然数)。在此基础上,对不同发送天线数(n=2,3,4,5,6,7,8)的复正交空时分组码进行了蒙特卡洛仿真,从而验证了算法的有效性,并得出发射天线数与系统误比特率性能呈正比,且随着发射天线数目的增加,误比特率性能改善的程度越来越小。 相似文献
6.
7.
8.
9.
10.
依据空时分组码的复正交设计理论的推广,推导了基于坐标间交织正交设计(CIOD)的空时分组码设计方法,并根据Alamouti正交接收原理,对接收信号依次经过矢量正交变换、矢量虚部交换和矢量加权旋转处理,进行解调运算。最后在准静态平坦Rayleigh衰落信道中,对802.16d/e中使用的4发射天线基于CIOD的发射分集配置方案A进行了性能仿真,结果表明这些码具有较低的译码复杂性,与基于复数正交设计的空时分组码的译码复杂度相当,但性能要好。 相似文献
11.
12.
A new differential space-time code, called differential space-time block-diagonal code (DSTBDC), is proposed for multiple-input multiple-output (MIMO) wireless communication systems. By exploiting the block-diagonal construction of DSTBDC, we can design a variety of high-performance DSTBDC, especially for the cases of large numbers of transmit antennas and high date rates. In flat fading channels, DSTBDC outperforms traditional differential space-time codes if the data rate is higher than 1 bps/Hz, especially when the number of transmit antennas is large. In frequency-selective fading channels, multiple-input multiple-output orthogonal frequency-division multiplexing (MIMO-OFDM) systems using DSTBDC have the powerful ability to achieve very high diversity gain in space, time, and frequency simultaneously. Due to the special orthogonal construction, DSTBDC has a simple decoding algorithm. In addition, DSTBDC can significantly save the cost of radio frequency circuits. 相似文献
13.
14.
FENG Ang YIN QinYe & WANG HuiMing MOE Key Laboratory for Intelligent Networks Network Security Xi'an Jiaotong University Xi'an China 《中国科学:信息科学(英文版)》2011,(9):1905-1915
Transmit diversity is an important multiple-input multiple-output (MIMO) approach to improve the transmission reliability;however,it is usually designed with maximum-likelihood detection.In this paper,we investigate a simple transceiver structure for single-carrier MIMO systems,in which the cyclic-delay time-reversal space-time block code (CDTR-STBC) is employed at the transmitter,and the frequency-domain decision-feedback equalization (FD-DFE) is used at the receiver.We separate the transmit antennas into ... 相似文献
15.
S. Jukna 《Information Processing Letters》2009,109(5):286-289
We are interested in proving exponential lower bounds on the size of nondeterministic D-way branching programs computing functions in linear time, that is, in time at most kn for a constant k. Ajtai has proved such lower bounds for explicit functions over domains D of size about n, and Beame, Saks and Thathachar for functions over domains of size about k22. We prove an exponential lower bound 2Ω(n/ck) for an explicit function over substantially smaller domain D of size about k2. Our function is a universal function of linear codes. 相似文献
16.
In this paper,we present a construction of complex orthogonal design for space-time block codes in any number of antennas.Our construction achieves both the maximal rate and minimal delay.So far as we know,our construction is the first explicit-form construction,which has asymptotically optimal time complexity and space complexity.And new representation of complex orthogonal design might bring advantages in analyzing some properties.In addition,when the number of antennas n ≡ 1,2,3(mod 4),our construction satisfies transceiver signal linearization property,which allows for design of low complexity channel equalizers and interference suppressing filters. 相似文献
17.
采用一种新型的分层空时编码——随机分层空时编码(RLST),针对其在TD-LTE系统中的应用进行了研究,通过对理论的分析,进行了RLST和V-BLAST在CDMA结构下的性能比较,并对应用RLST结构的接收机在不同信道环境下的性能比较,最后通过仿真结果表明了使用RLST结构的优越性,也证明了针对RLST结构提出的迭代多用户接收算法的正确性。 相似文献