Generalized mutual information (GMI) is used to compute achievable rates for fading channels with various types of channel state information at the transmitter (CSIT) and receiver (CSIR). The GMI is based on variations of auxiliary channel models with additive white Gaussian noise (AWGN). One variation is based on reverse channel models that give the largest rates but are challenging to optimize. A second variation is for receivers unaware of the CSIT where adaptive symbols achieve capacity. The GMI is then based on forward models with inputs that are linear functions of the adaptive symbol's entries. For scalar channels, the maximum GMI is achieved by a conventional codebook, and where the amplitude and phase of each channel symbol are modified based on the CSIT. A third variation partitions the channel output alphabet and has a different auxiliary model for each subset of the partition. The partitioning helps to determine the capacity scaling at high signal to noise ratios. A class of power control policies is described for partial CSIR, including a truncated minimum mean square error policy for full CSIT. Several examples for fading channels with AWGN illustrate the theory, with a focus on on-off fading and Rayleigh fading. The capacity results generalize to block fading channels with in-block feedback, including capacity expressions based on mutual information and directed information.
翻译:通用共同信息(GMI)用于计算通过发射机和接收器(CSIR)的各类频道状态信息淡化渠道的可实现速率。GMI基于辅助频道模型与添加白高斯噪音(AWGN)的变异。一种变异基于提供最大速率但具有优化挑战性的反向频道模型。第二个变异适用于在适应性符号达到能力的情况下对CSIT不知情的接收者。然后,GMI基于具有适应性符号条目直线功能的投入的远方模型。对于变异频道而言,最大GNI是通过常规代码手册实现的,而每个频道符号的振动度和阶段则根据CSIT进行修改。第三个变异模式以提供最大速率,对频道输出字母进行截断,对每个分区的每个子都有不同的辅助模型。分割有助于确定在高信号到噪音比率时的能力缩放。对部分CSIR的电源控制政策作了描述,包括全CSIT的微调最低平均差政策。几个关于淡化频道的例子,包括以CSSIIT为基础的平面反馈能力模型和平方位分析结果。</s>