Basic of Wireless Communication - Part V — Lesson 5

This lesson covers the multipath fading, and the use of Orthogonal Frequency Division Multiplexing (OFDM). It explains how signals are transmitted and received in air, the effects of obstacles on signal paths, and how OFDM helps mitigate delay spread. The lesson also discusses the impact of OFDM on power amplifier linearity and the concept of spectral regrowth. It further delves into mobile RF communication, frequency reuse, and diversity techniques to improve signal reception. The lesson concludes with an introduction to multiple access techniques.

Video Highlights

00:25 - Effect of multipath fading in wireless communication
04:08 - Concept of Orthogonal Frequency Division Multiplexing (OFDM)
11:57 - Discussion on the impact of OFDM on power amplifier linearity
21:13 - Explanation of mobile RF communication and the concept of frequency reuse
26:36 - Issues of diversity and delay spread in mobile communication
28:33 - Introduction to multiple access techniques in mobile communication

Key Takeaways

- Wireless communication involves various modulation schemes, including analog and digital modulation.
- Multipath padding is a common issue in wireless communication, caused by signals taking different paths due to obstacles.
- Orthogonal Frequency Division Multiplexing (OFDM) is used to mitigate the effects of delay spread.
- OFDM imposes severe linearity requirements on power amplifiers, leading to issues like spectral regrowth.
- Mobile RF communication involves downlink and uplink channels, and the concept of frequency reuse is implemented in a cellular structure.
- Diversity techniques, including space, frequency, and time diversity, can be used to improve signal reception.