Why In Manchester encoding, the bit rate is half of the baud rate?
I think baud rate is the rate of the symbols, and if each symbol contains n bit, then the bit rate should be n x baud rate
In Ethernet( Manchester encoding) ,if bit rate is half of the baud rate, then a symbol contains 1/2 bit ? As far as I know, bit rate should at least not less than symbol rate (baud rate).
About the relationship of baud rate and bit rate, my understanding have no problems, yet when it comes to the Manchester code, it's totally counterintuitive, could anyone explain about these?
Answer
Bit rate is related to the speed of the transmission of the digital bit, while baudrate is related to the speed of change of symbols, which are significancies in analog signal. These can be either in amplitude, frequency or phase or more complex modulation methods. In manchester encoding, one bit is reprsented by two different levels of voltage. Therefore, lets say if you want to transfer 1Mbit digital data in one second, then you will need to make ~ 2 million changes in the level of the analogous signal. That is why, your bit rate will be 1Mbs, while your baud rate will be 2M bauds.
In NRZ encoding, one bit is represented by one symbol. Therfore rates will be equal.