Multi level Digital Modulation

Multi-level digital modulation schemes are used to increase bit rate in data communications. Ordinary modulation techniques such as ASK, FSK and PSK are 2-level modulation schemes. They can transmit only 1- bit/sec.

To increase the bit rate (or data rate), we should be able to transmit more than 1-bit per second. This can be achieved by using multi-level modulation techniques. BAUD RATE is an important term related to multi-level modulation.

Baud rate: is defined as number of symbols per sec. Example of one symbol of carrier waveform is shown below:

Generally in 2-level modulations, only 1-bit can be transmitted in one cycle or symbol. In multi-level modulation, we can transmit more than one bit per symbol.

2 level modulation ----- 2 = 21 ----- 1 bit per symbol is transmitted
4 level modulation ----- 4 = 22 ----- 2 bits per symbol is transmitted
8 level modulation ----- 8 = 23 ----- 3 bits per symbol is transmitted etc.


Multi level Digital Modulation


Gopal Krishna

Hey Engineers, welcome to the award-winning blog,Engineers Tutor. I'm Gopal Krishna. a professional engineer & blogger from Andhra Pradesh, India. Notes and Video Materials for Engineering in Electronics, Communications and Computer Science subjects are added. "A blog to support Electronics, Electrical communication and computer students".

Leave a Reply

Your email address will not be published. Required fields are marked *

Translate »