capacity_MIMO信道容量.docxVIP

Capacity of Multi-antenna Gaussian Channels We investigate(研究) the use of multiple transmitting and/or receiving antennas for single user communications over the additive Gaussian channel（加性高斯白噪声信道） with and without fading. We derive （推导）formulas（公式） for the capacities and error exponents（范例） of such channels, and describe computational procedures（计算过程） to evaluate such formulas. We show that the potential gains of such multi-antenna systems over single-antenna systems is rather large under independence assumptions（假定） for the fades and noises at different receiving antennas. 1 Introduction We will consider a single user Gaussian channel with multiple transmitting and/or receiving antennas. We will denote the number of transmitting antennas by t and the number of receiving antennas by r. We will exclusively deal with a linear model in which the received vector depends on the transmitted vector via where H is a r *t complex matrix and n is zero-mean complex Gaussian noise with independent, equal variance(方差) real and imaginary parts. We assume , that is, the noises corrupting the dffierent receivers are independent. The transmitter is constrained（受制于） in its total power to P, Equivalently, since , and expectation and trace commute, This second form of the power constraint（限制） will prove more useful in the upcoming discussion. We will consider several scenarios（情景） for the matrix H: 1. H is deterministic.（确定性的） 2. H is a random matrix (for which we shall use the notation H), chosen according to a probability distribution（概率分布）, and each use of the channel corresponds（相当于） to an independent realization of H. 3. H is a random matrix, but is fixed once it is chosen. The main focus of this paper in on the last two of these cases. The first case is included so as to expose（显示） the techniques（方法） used in the later cases in a more familiar context. In the cases when H is random, we will assume that its entries form an i.i.d. Gaussian collection with zero-mean, independent r