Now we will go over representation of a digital signal. A digital signal has two values. Therefore, it is better to transmit the digital signal without errors. A digital signal is represented as bit interval and bit rate. Bit interval is the time spent to transmit a bit. Bit rate refers to the number of bits transmitted per second. The unit of bit rate is bps, bits per second. As shown in the figure, there are 8 bits for one second. Therefore, the signal is an 8 bps signal, or the bit interval is 1/8 second.