This lesson delves into the study of the MIMO channel, frequency selectivity, and the impact of different aspects on different channels. The lesson also discusses the concept of flat fading condition and frequency selective fading conditions. For instance, it explains how an impulse launched gives rise to frequency selective characteristics. The lesson further explores the concept of Doppler spectrum, signal correlation, and the calculation of coherence time and coherence bandwidth. It concludes with a discussion on MIMO signal analysis and the assumptions made in this analysis.
00:18 - Introduction
01:09 - Frequency selective characteristics and the echoes
05:55 - Correlation analysis of the signal
09:30 - Time evolution and coherence bandwidth
16:50 - Space dimension
23:24 - Homogeneous channels
26:42 - SIMO, MISO and MIMI channels
30:11 - The classical IID channel
- Understanding the propagation characteristics and large scale propagation models is crucial in the evolution of Air Interface towards 5G.
- The study of the MIMO channel involves understanding the impact of different aspects on different channels.
- Echoes and frequency selective characteristics play a significant role in signal propagation.
- Scatterers and reflectors contribute to the delay and magnitude of signals.
- Gaussian random variables and Rayleigh distribution are essential concepts in signal propagation.
- Coherence time and bandwidth are critical in determining the range of frequencies over which the channel is not fluctuating.
- In MIMO systems, correlation plays a significant role in signal analysis.