Unequal error protection in multi-carrier transmission
AssigneeFujitsu Limited
InventorsMakoto Yoshida, Eizou Ishizu
Life of this patent
Estimating the term…
Abstract
A method of providing unequal error protection in a multi-carrier transmission, includes the steps of coding data for a multi-carrier-symbol duration by a coding process of a given minimum code distance, the given minimum code distance being a minimum of a distance between two codes that is measured in multidimensional code space with N sub-carriers; and changing the minimum code distance for each multi-carrier-symbol duration by changing the coding process.
Claims9
A method of providing unequal error protection in a multi-carrier transmission which divides a transmission band into a plurality of carrier frequencies, each carrier frequency being modulated to transmit coded data, comprising the steps of:
- coding data for a multi-carrier-symbol duration by a coding process of a given minimum code distance, said given minimum code distance being a minimum of a distance between two codewords that is measured in multidimensional code space with N sub-carriers, each of the sub-carriers having a different frequency;
- and
- changing the minimum code distance for each multi-carrier-symbol duration by changing the coding process.
A coding device for providing unequal error protection in a multi-carrier transmission which divides a transmission band into a plurality of carrier frequencies, each carrier frequency being modulated to transmit coded data, comprising:
- a plurality of coding units, each of which codes a corresponding data frame of an information bit signal by a coding process of a given minimum code distance specific to a corresponding coding unit so as to output a coded bit signal;
- a selector unit which successively selects one of said plurality of coding units, and outputs the coded bit signal supplied from the selected one of said plurality of coding units;
- and
- a mapping unit which maps the coded bit signal output from said selector unit to complex signals corresponding to sub-carriers, each of the sub-carriers having a different frequency.
A decoding device for decoding codes protected by unequal error protection and transmitted through a plurality of sub-carriers having a different frequency in a multi-carrier-transmission system which divides a transmission band into a plurality of carrier frequencies, each carrier frequency being modulated to transmit coded data, comprising a plurality of decoding units, which decode codes for a multi-carrier-symbol duration wherein a minimum code distance between two codewords that is measured in multidimensional code space with the plurality of sub-carriers differs for each decoding unit, said decoding units being configured to perform a maximum likelihood method to estimate transmitted codewords with respect to received data signal of said plurality of sub-carriers.
A decoding device for decoding received signals corresponding to a plurality of sub-carriers transmitted in a multi-carrier-transmission system, comprising:
- a timing control unit which generates data control signals such that each of the data control signals varies over time to present various patterns within a corresponding multi-carrier-symbol duration;
- a plurality of coding units, each of which codes a corresponding one of the data control signals by a coding process of a given minimum code distance specific to a corresponding coding unit so as to output a coded bit signal;
- a mapping unit which maps the coded bit signal output from a selected one of said plurality of coding units to complex signals corresponding to the sub-carriers;
- and
- a code-distance-calculation unit which calculates a code distance between the complex signals and the received signals with respect to each of the various patterns of the corresponding one of the data control signals within a corresponding multi-carrier-symbol duration, wherein one of the various patterns providing a smallest code distance is selected as a decoding result of the corresponding received signals.
Dependencies are inferred from the claim text.