摘要 |
A method of transmitting QPSK digital signals in which each 2-digit binary number, referred to as a symbol, is assigned a phase of a carrier, and symbols are added to enable error correction at the receiver. The error correction code is a product code. To obtain transparency to phase rotations, the I bits (I<SUB>1</SUB>, I<SUB>3</SUB>, etc.) and the Q bits (Q<SUB>2</SUB>, Q<SUB>4</SUB>, etc.) of a symbol to be transmitted are placed in different rows but in the same column, so that each row contains only one type of bit, I or Q. The error correction coding is effected: row by row (N<SUB>C</SUB>-K<SUB>C</SUB>), and by pairs of adjacent columns, and the code I (or Q) bits of two associated adjacent columns are deduced from the I (or Q) bits of the two columns.
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