METHOD AND APPARATUS FOR MAPPING/DEMAPPING MODULATION SYMBOLS IN A MOBILE COMMUNICATION SYSTEM

• US 20080267122A1
• Filed: 04/14/2008
• Published: 10/30/2008
• Est. Priority Date: 04/13/2007
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Han, Jin-Kyu, Cho, Joon-Young, Lee, Ju-Ho, Kwon, Hwan-Joon
• Granted Patent: US 8,942,079 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04L 25/0226 sounding signals per se
• CPC Class Codes: H04L 5/0023 Time-frequency-space
• CPC Class Codes: H04L 5/0037 Inter-user or inter-terminal allocation
• CPC Class Codes: H04L 5/0044 allocation of payload
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver

Abstract

A method for mapping wireless resources of reference symbols for channel state estimation and modulation symbols for user information transmission in a transmitter of an Orthogonal Frequency Division Multiplexing (OFDM) mobile communication system is disclosed. The mapping method includes channel-encoding and modulating a user information stream to be transmitted, and then generating a systematic symbol stream and a parity symbol stream; and preferentially arranging systematic modulation symbols in resource elements of a symbol including no reference symbol, and then arranging parity modulation symbols in remaining resource elements.

Claims

1. A method for mapping wireless resources of reference symbols for channel state estimation and modulation symbols for user information transmission in a transmitter of an Orthogonal Frequency Division Multiplexing (OFDM) mobile communication system, the method comprising:

channel-encoding and modulating a user information stream to be transmitted;

generating a systematic symbol stream containing systematic modulation symbols and a parity symbol stream containing parity modulation symbols using the user information stream; and

preferentially arranging the systematic modulation symbols in resource elements of a symbol including no reference symbol, and then arranging the parity modulation symbols in remaining resource elements.

2. The method of claim 1, wherein generating a systematic symbol stream and a parity symbol stream comprises:

dividing channel-coded bits into a systematic bit stream and a parity bit stream;

modulating the systematic bit stream and the parity bit stream separately, to convert them into a systematic symbol stream and a parity symbol stream, respectively; and

interleaving the systematic symbol stream and the parity symbol stream independently.

3. The method of claim 1, wherein arranging modulation symbols in resource elements comprises:

preferentially and sequentially arranging the systematic modulation symbols along a frequency domain in one symbol interval including no reference symbol, and then sequentially arranging the systematic modulation symbols along the frequency domain in a next symbol interval including no reference symbol.

4. The method of claim 1, wherein arranging modulation symbols in resource elements comprises:

preferentially and sequentially arranging the systematic modulation symbols along a time domain in a symbol interval including no reference symbol in one frequency tone, and then sequentially arranging the systematic modulation symbols along the time domain in the symbol interval in a next frequency tone.

5. A method for demapping wireless resources of reference symbols for channel state estimation and modulation symbols for user information transmission in a receiver of an Orthogonal Frequency Division Multiplexing (OFDM) mobile communication system, the method comprising:

detecting, from a received signal, a systematic symbol stream containing systematic modulation symbols arranged in resource elements of a symbol including no reference symbol and detecting a parity symbol stream containing parity modulation symbols arranged in remaining resource elements;

deinterleaving the systematic symbol stream and the parity symbol stream separately;

demodulating the systematic symbol stream and the parity symbol stream independently, to convert them into a systematic bit stream and a parity bit stream, respectively; and

combining the systematic bit stream with the parity bit stream, and decoding the combined bit stream to generate a user information stream.

6. An apparatus for mapping modulation symbols according to power allocation for reference symbols in a transmitter of a mobile communication system, the apparatus comprising:

a channel encoder for converting an input user bit stream into a coded bit stream;

a demultiplexer for demultiplexing the coded bit stream into a systematic bit stream and a parity bit stream;

a first modulator for modulating the systematic bit stream;

a second modulator for modulating the parity bit stream;

a first interleaver for interleaving the systematic bit stream output from the first modulator;

a second interleaver for interleaving the parity bit stream output from the second modulator; and

a resource element mapper for preferentially arranging the systematic bit stream output from the first interleaver in resource elements of a symbol including no reference symbol, and arranging the parity bit stream output from the second interleaver in remaining resource elements.

7. The apparatus of claim 6, wherein the resource element mapper preferentially and sequentially arranges systematic modulation symbols along a frequency domain in one symbol interval including no reference symbol, and then sequentially arranges systematic modulation symbols along the frequency domain in a next symbol interval including no reference symbol.

8. The apparatus of claim 6, wherein the resource element mapper preferentially and sequentially arranges systematic modulation symbols along a time domain in a symbol interval including no reference symbol in one frequency tone, and then sequentially arranges systematic modulation symbols along the time domain in the symbol interval in a next frequency tone.

9. An apparatus for demapping modulation symbols according to power allocation for reference symbols in a receiver of a mobile communication system, the apparatus comprising:

a reception processor for converting a received radio signal into baseband data;

a resource element demapper for detecting, from among symbols output from the reception processor, a systematic symbol stream arranged in resource elements of a symbol including no reference symbol and detecting a parity symbol stream arranged in remaining resource elements;

a first deinterleaver for deinterleaving the systematic symbol stream;

a second deinterleaver for deinterleaving the parity symbol stream;

a first demodulator for demodulating the systematic symbol stream output from the first deinterleaver;

a second demodulator for demodulating the parity symbol stream output from the second deinterleaver;

a multiplexer for multiplexing the systematic bit stream and the parity bit stream output from the first and second demodulators; and

a channel decoder for converting the bit stream output from the multiplexer into a decoded user bit stream.