 Capacity-approaching codes

Capacity-approaching codes are a class of error-correcting codes that are designed to achieve performance close to the theoretical limits of capacity defined by Shannon's channel capacity theorem. Shannon's theorem states that there is a maximum rate of information that can be transmitted over a communication channel without error, given a particular signal-to-noise ratio. The challenge in practical communication systems is to approach this limit in a way that allows for reliable communication despite the presence of noise and other impairments.