Advantech AMT-70, Инструкция по установке и эксплуатации

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AMT-70/AMT-73/AMT-75 Installation and Operation
CHAPTER 9 TURBO CODE DETAILS
A basic understanding in Turbo Product Coding is followed by the specific AMT-70 Turbo Product
Code details.
9.1
Turbo Product Code Overview
When data is encoded using Turbo Product Codes, it passes through four stages. First, a cyclic
redundancy check-word (CRC) is inserted into the uncoded data. This is then scrambled and then
Turbo encoded. Finally, framing marks are inserted into the coded data to enable decoding.
Turbo Product Codes are either two- or three-dimensional codes. Blocks of data are formed into 2D
or 3D arrays. The raw data is then encoded in each axis, using the basic Hamming or Parity codes.
In this case, a 2D code is being applied,
so the uncoded data is formed into a
square 2D array. In this case, the array
of uncoded data is 57 x 57 = 3249 bits in
size.
The component code is then applied first
over one axis. This adds 7 error
correction-coding (ECC) bits to each row
of data.
116
CRC
Insert
Scrambler TPC
Encoder
Framer
Uncoded Data
57 bits
Uncoded Data
57 bits
ECC Bits
64 bits