Comparison of Mixed Diversity Schemes to Enhance Reliability of Wireless Networks

Erraticness of the radio spectrum makes communication on wireless networks scarcely deterministic, which renders them hardly suitable for the use in application scenarios that demand high reliability, e.g., industrial wireless control systems. To counteract unpredictable phenomena like electromagnetic noise, moving obstacles, and collisions with interfering traffic, diversity in time, frequency, and space is customarily exploited. Recently, a number of solutions have appeared, possibly relying on redundant communication hardware, that combine more than one diversity scheme. In this paper, such strategies are analyzed using a simple, yet significant, mathematical model, and their performance compared to determine trade-offs between implementation complexity and the achieved level of dependability.