基于OFDM的无线传感器系统在移动多路径通道上的合作时空/频率多样性的影响
Jiayi Zhang1, Hamid Gharavi1, Bin Hu1
1National Institute of Standards and Technology, Gaithersburg, MD 20899-8920, USA.
IET wireless sensor systems
|April 15, 2024
概括
合作线性分散编码 (LDC) 通过提供时空/频率多样性收益来增强无线传感器网络. 这种方法在复杂的色通道中优于传统代码,特别是在多个合作节点的情况下.
科学领域:
- 无线通信系统无线通信系统
- 无线网络的信号处理.
- 在无线通信中的信息理论.
背景情况:
- 虚拟多输入多输出 (MIMO) 系统需要强大的编码方案.
- 在无线传感器系统中,正角频率分割复杂化 (OFDM) 被广泛使用.
- 实现时空/频率 (ST/SF) 多样性对于在色通道上的可靠通信至关重要.
研究的目的:
- 在基于OFDM的无线传感器系统中研究合作型线性分散编码 (LDC) 的空间多样性应用.
- 评估合作性最不发达国家支持的ST/SF-OFDM在时间/频率选择性色通道上的表现.
- 将合作性最不发达国家与合作性直角块代码进行ST/SF多样性收益的比较.
主要方法:
- 实现虚拟MIMO系统的合作线性分散编码 (LDC).
- 在ST/SF多样性方面,LDC应用于直角频率分割复杂化 (OFDM).
- 在变频道多普勒和延迟差距下分析系统性能.
- 与合作直角块代码 (例如,Tarokh的代码) 的比较.
主要成果:
- 合作性最不发达国家援助的ST/SF-OFDM在系统配置 (节点,时段,频率调) 中提供了灵活性.
- ST-OFDM计划的多样性收益对道多普勒差异敏感.
- SF-OFDM计划的表现主要受到延迟差的影响.
- 合作的LDC辅助的ST/SF-OFDM超越了合作的直角块代码,当两个以上的节点参与高多普勒/延迟扩散环境时.
结论:
- 合作性LDC提供了一种灵活和有效的方法,用于在基于OFDM的无线传感器系统中实现ST/SF多样性.
- 在ST-OFDM和SF-OFDM之间做出选择取决于主导通道特征 (多普勒与延迟扩散).
- 合作型LDC在具有多个合作节点的具有挑战性的无线通道条件下表现优于传统代码.
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