Waveforms in 3G - Part I — Lesson 2

This lesson covers the importance of pulse shape in spectrum occupancy and out-of-band reduction. It covers the shift keying techniques used in the communication system. It discusses on the third-generation system and the concept of direct sequence spread spectrum. It also covers the modulator and demodulator block diagrams. This lesson concludes with Rake receiver and multipath reception.

Video Highlights

00:18 - Introduction and recap of previous lesson
05:57 - QPSK and offset QPSK and how they affect the signal as it passes through the high power amplifier
08:51 - How the choice of pulse shape influences the spectrum occupancy and out of band reduction
12:04 - Introduction to the third generation system
23:43 - DS-QPSK modulator and de-modulator
25:23 - Rake receiver and multipath reception

Key Takeaways

- Different pulse shapes, including rectangular and raised cosine pulse shapes, have varying effects on signal representation.
- The Gaussian minimum shift keying pulse shape is optimized for bandwidth and T parameters.
- The choice of pulse shape significantly influences spectrum occupancy and out-of-band reduction.
- The third-generation system uses a direct sequence spread spectrum, which is different from the second-generation system.