Understanding Mobile Radio Propagation-13 — Lesson 13

This lesson covers the concept of mobile radio propagation, focusing on Rayleigh and Ricean fading distributions. It explains how these distributions affect the quality of service in mobile communication. The lesson also discusses the level crossing rate and the average duration of fade, two parameters that significantly impact the quality of service. It further explains the effects of different factors such as vehicular speed, frequency of operation, and threshold value on these parameters. For instance, it illustrates how increasing vehicular speed decreases the average duration of fade, improving the situation. The lesson concludes with practical examples demonstrating these concepts.

Video Highlights

01:18 - Introduction to the lecture on mobile radio propagation, including a summary of previous learnings and an outline of the current lecture's content
03:53 - Discussion on the effects of the Doppler shift and coherence bandwidth on the type of fading
05:29 - Explanation of fading distributions and their impact on the envelop of the received signal
12:55 - Discussion on the impact of the number of scatterers and the speed of the vehicle on the level crossing rate and the average duration of fade
14:16 - Explanation of the Ricean fading and the conditions under which it occurs
30:40 - Discussion on the level crossing rate and the average duration of fade, including their definitions and calculations
54:18 - Conclusion and summary of the lecture

Key Takeaways

1. Rayleigh and Ricean fading distributions are commonly used in mobile radio propagation.
2. The level crossing rate and the average duration of fade are crucial parameters that affect the quality of service in mobile communication.
3. The level crossing rate indicates how often the signal level crosses a specified threshold in a positive direction.
4. The average duration of fade represents the average period during which the received signal is below a specified level.
5. Factors such as vehicular speed, frequency of operation, and threshold value significantly impact these parameters.
6. Practical examples help in understanding the application of these concepts in real-world scenarios.