Directional antennas and beamforming techniques that bring promising transmission gain to the wireless links are widely incorporated in the system-level analysis of wireless networks. In many existing studies, the beamforming gain model to calculate the beamforming gain considers beamforming pattern and aligned as well as misaligned cases. However, the channel properties, e.g., the KK factor and the spatial distribution of multi-paths, are neglected, which could significantly influence the beamforming gain. In this paper, a general beamforming gain model is appropriately defined, while the traditional beamforming gain model is proved to be only a special case in the proposed general model by considering an oversimplified channel with no angular spread. In light of this, expressions of the received signal amplitude and the beamforming gain are rigorously derived for narrowband fading and wideband statistical mmWave channels, respectively. Thorough comparison between the proposed beamforming gain model and the traditional beamforming gain is provided, which demonstrates and validates that the traditional model incorrectly captures the beamforming gain and thereby, leads to inaccurate system-level network analysis. To this end, the effectiveness and importance of the proposed general beamforming gain model are revealed, particularly for millimeter-wave wideband systems.

中文翻译：

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窄带和宽带无线网络性能评估和分析的波束成形增益模型


定向天线和波束成形技术为无线链路带来了良好的传输增益，被广泛纳入无线网络的系统级分析中。在许多现有研究中，计算波束成形增益的波束成形增益模型考虑了波束成形模式以及对齐和未对齐的情况。然而，忽略了信道特性，例如KK因子和多径的空间分布，这可能显着影响波束形成增益。在本文中，适当地定义了通用波束成形增益模型，而通过考虑没有角展度的过度简化的信道，证明传统波束成形增益模型只是所提出的通用模型中的特殊情况。鉴于此，分别针对窄带衰落和宽带统计毫米波信道严格推导了接收信号幅度和波束成形增益的表达式。提供了所提出的波束成形增益模型与传统波束成形增益之间的彻底比较，这证明并验证了传统模型错误地捕获了波束成形增益，从而导致系统级网络分析不准确。为此，揭示了所提出的通用波束形成增益模型的有效性和重要性，特别是对于毫米波宽带系统。