In a SATCOM system, MCPC differs from VCM in how channels are treated. Which statement describes MCPC?

• A. MCPC uses adaptive modulation per channel.
• B. MCPC uses a fixed coding rate for all channels.
• C. MCPC uses a single modulation and coding for all channels.
• D. MCPC is used for uplink only.

Answer: (C)

MCPC means all channels on a single carrier share one modulation scheme and one coding rate. This lets every channel have the same level of protection and data rate, making the transponder behavior and receiver design simpler and the bandwidth allocation predictable. In contrast, VCM assigns different modulation and coding to each channel based on conditions and service needs, optimizing spectral efficiency at the cost of added complexity. The statement that describes MCPC is the one that states a single modulation and coding for all channels.