Orthogonal frequency division multiplexing/modulation communication system for improving ability of data transmission and method thereof
First Claim
1. An OFDM (Orthogonal Frequency Division Multiplexing) communication system comprising:
- a Reed-Solomon interleaver for dispersing Reed-Solomon symbol elements existing in the same positions, obtained by Reed-Solomon coding input information data blocks, to sub-channels of the OFDM symbols, for interleaving;
a sub-channel repeater for converting the interleaved signals to parallel data blocks, repeating the parallel data blocks with a predetermined number of times, and transmitting the repeated data blocks over corresponding sub-channels;
a sub-channel assignor for adding the sub-channel data blocks and the pilot sub-channel data blocks, and dynamically assigning sub-channels for transmitting the sub-channel data blocks each time the added sub-channel data blocks are received, according to input time points;
a sub-channel scrambler for mapping the assigned sub-channel signals according to a predetermined modulation mode, scrambling pilot sub-channel data blocks among the mapped sub-channel data blocks with a pilot scrambling code, and scrambling the scrambled pilot sub-channel data blocks and the remaining mapped sub-channel data blocks with the scrambling code;
a minimum PAPR (Peak-to-Average Power Ratio) selector for IFFT (Inverse Fast Fourier Transformer)-transforming a signal output from the sub-channel scrambler, and selecting sub-channel data blocks having a minimum PAPR among the LEFT-transformed sub-channel data blocks; and
antennas for transmitting the sub-channel data blocks output from the selector as an in-phase signal having no phase offset, and alternately transmitting the sub-channel data blocks output from the selector as an in-phase signal having no phase offset and a phase-inversed signal having a 180°
-phase offset in a training symbol period.
6 Assignments
0 Petitions
Accused Products
Abstract
An Orthogonal Frequency Division Multiplexing (OFDM) communiation system and method for improving frequency utilization efficiency. In the system, a Reed-Solomon encoder codes input information data, and ouputs a Reed-Solomon block having a second number of Reed-Solomon symbols, each Reed-Solomon symbol having a first number of Reed-Solomon symbol elements. An interleaver receives the Reed-Solomon block, and disperses the Reed-Solomon symbol elements existing in a specified one Reed-Solomon symbol within the received Reed-Solomon block in the same sub-channel position in a fourth number of sub-channels of each of a third number of consecutive OFDM symbols.
-
Citations
25 Claims
-
1. An OFDM (Orthogonal Frequency Division Multiplexing) communication system comprising:
-
a Reed-Solomon interleaver for dispersing Reed-Solomon symbol elements existing in the same positions, obtained by Reed-Solomon coding input information data blocks, to sub-channels of the OFDM symbols, for interleaving; a sub-channel repeater for converting the interleaved signals to parallel data blocks, repeating the parallel data blocks with a predetermined number of times, and transmitting the repeated data blocks over corresponding sub-channels; a sub-channel assignor for adding the sub-channel data blocks and the pilot sub-channel data blocks, and dynamically assigning sub-channels for transmitting the sub-channel data blocks each time the added sub-channel data blocks are received, according to input time points; a sub-channel scrambler for mapping the assigned sub-channel signals according to a predetermined modulation mode, scrambling pilot sub-channel data blocks among the mapped sub-channel data blocks with a pilot scrambling code, and scrambling the scrambled pilot sub-channel data blocks and the remaining mapped sub-channel data blocks with the scrambling code; a minimum PAPR (Peak-to-Average Power Ratio) selector for IFFT (Inverse Fast Fourier Transformer)-transforming a signal output from the sub-channel scrambler, and selecting sub-channel data blocks having a minimum PAPR among the LEFT-transformed sub-channel data blocks; and antennas for transmitting the sub-channel data blocks output from the selector as an in-phase signal having no phase offset, and alternately transmitting the sub-channel data blocks output from the selector as an in-phase signal having no phase offset and a phase-inversed signal having a 180°
-phase offset in a training symbol period. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18)
-
-
19. A method of OFDM communication comprising the steps of:
-
Reed-Solomon interleaving for dispersing Reed-Solomon symbol elements existing in the same positions, obtained by Reed-Solomon coding input information data blocks, to sub-channels of the OFDM symbols, for interleaving; sub-channel repeating for converting the interleaved singles to parallel data blocks, repeating the parallel data blocks with a predetermined number of times, and transmitting the repeated data blocks over corresponding sub-channels; sub-channel assigning for adding the sub-channel data blocks and the pilot sub-channel data blocks, and dynamically assigning sub-channels for transmitting the sub-channel data blocks each time the added sub-channel data blocks are received, according to input time points; sub-channel scrambling for mapping the assigned sub-channel signals according to a predetermined modulation mode, scrambling pilot sub-channel data blocks among the mapped sub-channel data blocks with a pilot scrambling code; and
scrambling the scrambled pilot sub-channel data blocks and the remaining mapped sub-channel data blocks with the scrambling code;minimum PAPR selecting for IFFT-transforming a signal output from the sub-channel scrambler, and selecting sub-channel data blocks having a minimum PAPR among the IFFT-transformed sub-channel data blocks; and transmitting for transmitting the sub-channel data blocks output from the selector as an in-phase signal having no phase offset, and alternately transmitting the sub-channel data blocks output from the selector as an in-phase signal having no phase offset and a phase-inversed signal having a 180°
-phase offset in a training symbol period via antennas. - View Dependent Claims (20, 21, 22, 23, 24, 25)
-
Specification