On the Sphere Packing Error Exponent for Constant Subblock-Composition Codes

Constant subblock-composition codes (CSCCs) are a type of constrained codes in which codewords are partitioned into smaller subblocks with each subblock having the same composition. These constrained codes have applications in diverse fields such as simultaneous energy and information transfer, visible light communication, and design of low-cost authentication methods. In this paper, we characterize the sphere packing error exponent for CSCCs over discrete memoryless channels. We also derive computationally efficient bounds on the CSCC sphere packing error exponent, and show that these bounds are asymptotically tight in the subblock length. In addition, we present several numerical examples, highlighting the impact of subblock length, subblock-composition, and transmission rate, on the CSCC sphere packing error exponent.