Baud is a term used in digital communication to refer to the rate at which the signal changes. It is not directly related to the number of bits or bytes transmitted per unit time. Baud is a measure of the signaling rate or the number of signal events per second. Let's understand this concept in detail.

Understanding Baud

The term "baud" was originally used to indicate the number of signaling events per second in analog communication systems. In digital communication, baud refers to the number of signal events per second as well. However, in digital communication, each signal event can represent multiple bits.

Bits and Baud

In digital communication, the number of bits transmitted per unit time depends on the modulation scheme used. Modulation is the process of encoding information into a carrier signal. Different modulation schemes allow multiple bits to be represented by a single signal event.

For example, in a binary modulation scheme like binary phase-shift keying (BPSK), each signal event represents one bit. So, in this case, the number of bits transmitted per unit time is equal to the baud rate.

However, in more complex modulation schemes like quadrature amplitude modulation (QAM), each signal event can represent multiple bits. For instance, in 16-QAM, each signal event represents 4 bits. In this case, the number of bits transmitted per unit time is higher than the baud rate.

Conclusion

To summarize, baud refers to the rate at which the signal changes in digital communication. It is not directly related to the number of bits or bytes transmitted per unit time. The number of bits transmitted per unit time depends on the modulation scheme used. Baud is still important in digital communication as it indicates the rate at which the signal events occur, which has implications for the bandwidth and data rate of a communication system.