Data signaling rate

In telecommunication, data signaling rate (DSR), also known as gross bit rate, is the aggregate rate at which data passes a point in the transmission path of a data transmission system.

1. The DSR is usually expressed in bits per second.
2. The data signaling rate is given by ${\displaystyle \sum _{i=1}^{m}{\frac {\log _{2}{n_{i}}}{T_{i}}}}$ where m is the number of parallel channels, n_i is the number of significant conditions of the modulation in the i-th channel, and T_i is the unit interval, expressed in seconds, for the i-th channel.
3. For serial transmission in a single channel, the DSR reduces to (1/T)log₂n; with a two-condition modulation, i. e. n = 2, the DSR is 1/T, according to Hartley's law.
4. For parallel transmission with equal unit intervals and equal numbers of significant conditions on each channel, the DSR is (m/T)log₂n; in the case of a two-condition modulation, this reduces to m/T.
5. The DSR may be expressed in bauds, in which case, the factor log₂n_i in the above summation formula should be deleted when calculating bauds.
6. In synchronous binary signaling, the DSR in bits per second may be numerically the same as the modulation rate expressed in bauds. Signal processors, such as four-phase modems, cannot change the DSR, but the modulation rate depends on the line modulation scheme, in accordance with Note 4. For example, in a 2400 bit/s 4-phase sending modem, the signaling rate is 2400 bit/s on the serial input side, but the modulation rate is only 1200 bauds on the 4-phase output side.