Bauds
Baud rate is a measure of the
number of times per second a signal in a communications channel varies, or
makes a transaction between states (states being frequencies, voltage
levels, or phase angles). One baud is one such change. Thus, a 300-baud
modems’ signal changes state 300 times each second, while a 600-baud modems’
signal changes state 600 times per second.
Determining bits per second
Depending on the modulation technique used, a modem can transmit one bit—or
more or less than one—with each baud, or change state. The number of bits a
modem transmits per second is directly related to the number of bauds that
occur each second, but the numbers are not necessarily the same.
A way to look at it is bits per
second can also be obtained by dividing the modem’s baud rate by the rate by
the number of changes in state, or bauds, required to send one bit:
300 baud
----------------- = 150 bps
2 bauds per bit |
