Symbol rate
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In digital communications, the symbol rate is the bit rate divided by the number of bits transmitted in each symbol. Symbol rate is measured in symbols-per-second, hertz (Hz), or baud (Bd).
The term baud rate is synonymous with symbol rate, but is less frequently used today as it has in the past been commonly misused to mean bit rate or data rate.
In digital television transmission the symbol rate calculation is:
symbol rate in symbols per second = (Data rate in bits per second* 204)/(188 * bits per symbol)
The 204 is the number of bytes in a packet including the 16 trailing Reed-Solomon error checking and correction bytes. The 188 is the number of data bytes (187 bytes) plus the leading packet sync byte (0x47).
The bits per symbol is the modulation's power of 2. So for example in 64-QAM modulation 64 = 26 so the bits per symbol is 6.
Example:
given bit rate = 18096263
Modulation type = 64-QAM
then
