Use of pulse shaping in digital modulation

1. What is the purpose of pulse shaping?
2. What is pulse in digital communication?
3. Does OFDM use pulse shaping?
4. What is the advantage of the sinc pulse shape on the bandwidth and frequency domain?

What is the purpose of pulse shaping?

In electronics and telecommunications, pulse shaping is the process of changing the waveform of transmitted pulses to optimize the signal for its intended purpose or the communication channel. This is often done by limiting the bandwidth of the transmission and filtering the pulses to control intersymbol interference.

What is pulse in digital communication?

A pulse in signal processing is a rapid, transient change in the amplitude of a signal from a baseline value to a higher or lower value, followed by a rapid return to the baseline value.

Does OFDM use pulse shaping?

The principle of OFDM with pulse shaping has been introduced in [13]. One of the main criteria for pulse shape design is the time-frequency localization (TFL), which has been identified in [14] as an important target to achieve low out-of-band emissions and low interference induced in doubly dispersive channels.

What is the advantage of the sinc pulse shape on the bandwidth and frequency domain?

The advantages of the sinc pulse are similar to the advantages of the rectangular pulse, except that they hold in the frequency domain rather than in the time domain. It completely restricts the frequency content within a compact box so that we can tightly meet any bandwidth constraint.