Chapter 14: The Multiple Access Channel

Learning Objectives

• Define the discrete memoryless multiple access channel and characterize its capacity region as a pentagon in the rate plane
• Prove achievability of the MAC capacity region using joint typicality decoding
• Show that successive cancellation decoding achieves the corner points of the capacity region
• Derive the capacity region of the Gaussian MAC and compare it with orthogonal multiple access (TDMA/FDMA)
• Extend the capacity region to the vector (MIMO) Gaussian MAC with successive decoding and Gaussian inputs
• Characterize the $K$-user MAC capacity region via $2^K - 1$ subset inequalities and its polymatroidal structure
• Analyze the ergodic fading MAC under CSIR and CSIT, and understand opportunistic scheduling and multiuser diversity