What is the primary purpose of forward error correction (FEC) in digital radio?

What is the primary purpose of forward error correction (FEC) in digital radio?

• A. It increases data rate.
• B. It adds redundancy to detect and correct errors.
• C. It reduces spectrum occupancy.
• D. It encrypts data.

Answer: (B)

Forward error correction protects data by adding redundancy so the receiver can detect and correct errors without needing a retransmission. By encoding the original data into longer codewords that include parity information, the receiver can infer the most likely original bits even when some are corrupted by noise, interference, or fading in the radio channel. This improves reliability and can reduce latency in noisy conditions, because errors are repaired on the fly rather than asking for the data to be resent. The trade-off is that additional redundancy lowers the net data rate, since more bits are sent than the raw data alone. It isn’t about reducing spectrum usage or encrypting data, which are separate concerns.

Forward error correction protects data by adding redundancy so the receiver can detect and correct errors without needing a retransmission. By encoding the original data into longer codewords that include parity information, the receiver can infer the most likely original bits even when some are corrupted by noise, interference, or fading in the radio channel. This improves reliability and can reduce latency in noisy conditions, because errors are repaired on the fly rather than asking for the data to be resent. The trade-off is that additional redundancy lowers the net data rate, since more bits are sent than the raw data alone. It isn’t about reducing spectrum usage or encrypting data, which are separate concerns.