Methods and apparatus for interleaving in OFDM/OFDMA systems
AssigneeWi-LAN, Inc.
InventorsLingjie Li, Shiquan Wu
Life of this patent
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Abstract
An interleaver of an OFDM/OFDMA transceiver reshapes a binary vector to be transmitted into a matrix, rotates bits in respective columns of the matrix, divides respective rows of the matrix into an integer number of interleaving blocks, and interleaves the bits in the respective interleaving blocks.
Claims20
A method of interleaving a binary vector for transmission by an OFDM/OFDMA transmitter, comprising:
- generating a forward error correction encoded binary vector from binary data to be transmitted;
- reshaping the forward error correction encoded binary vector into a matrix;
- rotating bits in respective columns of the matrix;
- dividing the bits in respective rows of the matrix into an integer number of interleaving blocks;
- and
- interleaving the bits in the respective interleaving blocks until each interleaving block in the matrix has been interleaved,
- wherein the steps of reshaping the forward error correction encoded binary vector, rotating the bits, dividing the rows into interleaving blocks and interleaving the bits in each interleaving block are performed in a single bit reordering operation on bits in the forward error correction encoded binary vector using a rotation/interleaving index lookup table.
An orthogonal frequency-division multiplexing (OFDM) transceiver, comprising:
- generating a forward error correction encoded binary vector from binary data to be transmitted;
- a vector reshaper that reshapes a the forward error correction encoded binary vector into a matrix;
- a bit rotator that rotates bits in respective columns of the matrix;
- and
- an interleaver that divides respective rows of the matrix into an integer number of interleaving blocks, and interleaves the bits in the respective interleaving blocks until each interleaving block in the matrix has been interleaved,
- wherein the vector reshaper, the bit rotator and the interleaver comprise a single bit reordering operation that uses a rotation/interleaving index lookup table to reorder the bits in the forward error correction encoded binary vector.
An orthogonal frequency-division multiplexing multiple access (OFDMA) transceiver, comprising:
- generating a forward error correction encoded binary vector from binary data to be transmitted;
- a vector reshaper that reshapes a the forward error correction encoded binary vector into a matrix;
- a bit rotator that rotates bits in respective columns of the matrix;
- and
- an interleaver that divides the bits in respective rows of the matrix into an integer number of interleaving blocks, and interleaves the bits in the respective interleaving blocks until each interleaving block in the matrix has been interleaved,
- wherein the vector reshaper, the bit rotator, and the interleaver comprise a single bit reordering operation that uses a rotation/interleaving index lookup table to reorder the bits in the forward error correction encoded binary vector.
The OFDMA transceiver as claimed in 11 wherein the binary vectors are represented by v=[v1 v2 . . . Vm ] where vi=[bi,1′ . . . bi,Ni′] is abinary sequence received from an encoder, and the vector reshaper reshapes each vi into an Nb/sub by Ni/Nb/sub sub-matrix
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A method of interleaving a binary vector for transmission by an OFDM/OFDMA transmitter, comprising:
- generating a forward error correction encoded binary vector from binary data to be transmitted;
- reshaping the binary vector into a matrix;
- dividing the bits in respective rows of the matrix into an integer number of interleaving blocks;
- interleaving the bits in the respective interleaving blocks until each interleaving block in the matrix has been interleaved;
- and
- rotating bits in respective columns of the matrix,
- wherein the steps of reshaping the binary vector, dividing the rows into interleaving blocks, interleaving the bits in each interleaving block, and rotating the bits are performed in a single bit reordering operation on bits in the binary vector using a rotation/interleaving index lookup table.
Dependencies are inferred from the claim text.