摘要
针对空时编码级联波束形成的MIMO-OFDM系统,研究了考虑信道编码的自适应传输方案.本文首先从编码增益的角度出发,利用统计信道状态信息,推导了保证用户QoS星座距离的表达式;然后证明了研究的优化问题是凸规划问题,并根据库恩-塔克条件推出了最优功率和比特加载的封闭形式解;最后提出了一种非迭代的自适应资源分配算法.仿真结果表明,本文提出算法在保证用户QoS的情况下,能够有效逼近系统吞吐量的理论值,同时该算法具有计算复杂度低的特点,可以满足实时通信的要求;并且采用LDPC码的码率越低,系统吞吐量越大.
A transmission scheme based on channel coding was proposed for multiple-input multiple-output orthogonal frequency-division multiplexing system concatenating space-time block code with beamforming.Firstly,the constellation distance which guaranteed user's QoS was derived utilizing the statistical channel state information from the perspective of coding gain.Secondly,it was proved that this optimization problem was convex programming problem and the closed form solution for optimal power and bit loading was deduced according to Karush-Kuhn-Tucher conditions.Finally,an adaptive non-iterative resource allocation algorithm was put forward.The simulation results demonstrate that the algorithm is close to the theoretical value of the system throughput and has very low computational complexity which can meet the requirement of real-time communication.The lower the code rate of LDPC is,the higher the system throughput becomes.
出处
《电子学报》
EI
CAS
CSCD
北大核心
2010年第4期791-797,共7页
Acta Electronica Sinica
基金
航空基金(No.2009ZC52036)
江苏省自然科学基金(No.BK2007192)
移动通信国家重点实验室开放基金(No.200502)
关键词
多输入多输出
正交频分复用
统计信道状态信息
库恩-塔克条件
信道编码
multiple input multiple output
orthogonal frequency division multiplexing
statistical channel state information
karush-kuhn-tucher conditions
channel coding