The baud rate describes the Step speed of the transmission of symbols in a digital communication system. It indicates how many Symbols per second are sent via an interface or a transmission medium. The unit of the baud rate is Baud (Bd), where 1 Baud of one transmitted symbol per second (1 Bd = 1/s) corresponds.
A symbol represents a specific signal state that is used during data transmission to encode information. Depending on the transmission method, a symbol can be contain one or more bits. Therefore, the baud rate is not always identical to the bit rate.
The baud rate then corresponds exactly to the bit rate, if there are only two possible signal states per symbol (e.g. logical 0 and logical 1). In this case, each symbol has exactly One bit of information. However, if more than two different signal states are used, a symbol represent several bits simultaneously. This achieves a higher bit rate at the same baud rate.
For example, in modulation methods with four possible symbol states per symbol two bits are transmitted. In this case, the bit rate is twice as high as the baud rate.
In the industrial communication and measurement technology the baud rate is a central parameter in the configuration of serial interfaces. It determines the speed at which data is transferred between devices such as Measurement data acquisition systems, sensors, control systems and software are transmitted. With Delphin Technology systems, the baud rate is also set according to the connected devices when setting up communication interfaces - for example with serial protocols - in order to ensure reliable and error-free data transmission.