A robust maximin approach for MIMO communications with imperfect channel state information based on convex optimization
A robust maximin approach for MIMO communications with imperfect channel state information based on convex optimization
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DOI：
10.1109/tsp.2005.861084
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发表时间：
2006-01-01
影响因子：
5.4
通讯作者：
Lagunas, MA
中科院分区：
文献类型：
--
作者：
Pascual-Iserte, A;Palomar, DP;Lagunas, MA
本文考虑具有多个发射和接收天线的无线通信系统，即，多输入多输出（MIMO）信道。我们的目标是设计发射机根据一个不完美的信道估计，其中的错误是明确考虑到最大最小或最坏情况下的哲学，以获得一个强大的设计。鲁棒传输方案由正交空时分组码（OSTBC）组成，其输出通过信道估计的本征模传输，并在它们之间进行适当的功率分配。在接收机处，假设完美的信道知识来检测信号。将以信噪比最大化为目标的本征模功率分配设计问题转化为一个简单的凸优化问题，可以很容易地求解。在信道估计中考虑不同的误差源，例如来自估计过程的高斯噪声和来自信道估计的量化的误差等。对于高斯噪声的情况下，鲁棒功率分配承认一个封闭的形式的表达式。最后，所提出的设计的好处进行了评估和比较与纯OSTBC和非鲁棒方法。
This paper considers a wireless communication system with multiple transmit and receive antennas, i.e., a multiple-input-multiple-output (MIMO) channel. The objective is design the transmitter according to an imperfect channel estimate, where the errors are explicitly taken into account to obtain a robust design under the maximin or worst case philosophy. The robust transmission scheme is composed of an orthogonal space-time block code (OSTBC), whose outputs are transmitted through the eigenmodes of the channel estimate with an appropriate power allocation among them. At the receiver, the signal is detected assuming a perfect channel knowledge. The optimization problem corresponding to the design of the power allocation among the estimated eigenmodes, whose goal is the maximization of the signal-to-noise ratio (SNR), is transformed to a simple convex problem that can be easily solved. Different sources of errors are considered in the channel estimate, such as the Gaussian noise from the estimation process and the errors from the quantization of the channel estimate, among others. For the case of Gaussian noise, the robust power allocation admits a closed-form expression. Finally, the benefits of the proposed design are evaluated and compared with the pure OSTBC and nonrobust approaches.