A concatenated code is composed of two separate codes that are combined to form a larger code. There are two types of concatenation, serial and parallel concatenations. For both serial and parallel concatenation schemes, an interleaver is often used between the encoders to improve burst error correction capacity -A concatenated code is composed of two separate codes that are combined to form a larger code. There are two types of concatenation, serial and parallel concatenations.　　　　 For both serial and parallel concatenation schemes, an interleaver is often used between the encoders to improve burst error correction capacity