Symbol Rate Unit Explained | Generated by AI
Question: What is the unit of symbol rate (also known as baud rate or symbol transmission rate)?
Answer:
The correct answer is B. Baud.
Explanation in English:
- Symbol rate (also called baud rate, symbol transmission rate, or modulation rate) measures how many symbols (distinct signal elements) are transmitted per second.
- One symbol can represent one or more bits, depending on the modulation scheme (e.g., in BPSK 1 symbol = 1 bit, in 16-QAM 1 symbol = 4 bits).
- The standard unit for symbol rate is Baud (written as Bd or simply called “baud”).
Common units and their meanings:
- Bit/s (bps) → bit rate = number of bits transmitted per second
- Baud → symbol rate = number of symbols transmitted per second
- Byte → 8 bits (not a rate unit)
- Word → usually 16 or 32 bits depending on system (not a rate unit)
Key relationship:
Bit rate (bps) = Symbol rate (baud) × bits per symbol (log₂M)
Examples:
- BPSK: 1 bit per symbol → bit rate = baud rate
- QPSK: 2 bits per symbol → bit rate = 2 × baud rate
- 16-QAM: 4 bits per symbol → bit rate = 4 × baud rate
So the direct unit of symbol rate (码元速率) is Baud, not bit, byte, or word.
Therefore the correct choice is B. Baud.
References:
- None needed for this standard communication theory concept.