Enhanced HARQ Using Prioritized Bit Selection and Rearrangement for WiMAX Systems

Inter-symbol bit rearrangement for cooperative relay system

“…Sum: Calculate the sum of the minimum Euclidean distances of each bit in the 1st and 2nd transmissions; Maximal Sum: [1,2,··· ,2Mmcm] (…”

“…I is the number of the bit with maximal sum of two minimum Euclidean distances; Minimal Sum: [1,2,··· ,2Mmcm] …”

“…Bit rearrangement and constellation rearrangement (CoRe) are considered as two efficient methods to guarantee the data reliability. Bit rearrangement gains the constellation diversity through rearranging the bit sequence of each modulation symbol before mapped to constellations [2]. While CoRe rearranges the constellation mapping relationship to achieve the same goal [1].…”

“…The bit rearrangement scheme that based on minimizing the upper bounds on non-coded Bit Error Rate (BER) was proposed for high-order QAM modulation in [1], the transmitter may retransmit part of the symbol bits using low-order modulation and employ this bit rearrangement according to the novel optimization criterion. The bit rearrangement scheme in [2] classifies the priority of bits and rearranges the bits of each retransmission at most significant bit (MSB) positions or least significant bit (LSB) positions according to their priorities. There are two versions of CoRe in [3].…”