Method and apparatus for data packet relaying and data packet decoding

Patent metadata

Field	Value
Publication number	US-9036534-B2
Application number	US-200913266091-A
Country	US
Kind code	B2
Filing date	Apr 27, 2009
Priority date	Apr 27, 2009
Publication date	May 19, 2015
Grant date	May 19, 2015

Abstract

The present invention provides a technical scheme for forwarding data packets from one or more user terminals in a relay station, and a technical scheme for decoding the multiple data packets from the user terminals in a base station. The relay station performs network encoding on copies of multiple user terminal packets from one or more user terminals to obtain a network encoded data packet and sends the data packet to the base station. The base station receives copies of multiple user terminal packets from one or more user terminals, respectively, and a network encoded data packets from the relay station, and performs joint soft combining and decoding on them.

First claim

The invention claimed is:

1. A method of decoding data packets from user terminals in a base station of a wireless communication network, comprising:
in the base station, receiving copies of multiple user terminal packets from one or more user terminals and a network encoded data packet from a relay station, wherein said network encoded data packet is obtained after said relay station performs network coding on said copies of multiple user terminal packets respectively received from said one or more user terminals; and
in the base station, performing joint soft combining and decoding on said copies of multiple user terminal packets and said network encoded data packet.

2. A method of decoding data packets from user terminals in a base station of a wireless communication network, comprising:
receiving copies of multiple user terminal packets from one or more user terminals and a network encoded data packet from a relay station, wherein said network encoded data packet is obtained after said relay station performs network coding on said copies of multiple user terminal packets respectively received from said one or more user terminals; and
performing joint soft combining and decoding on said copies of multiple user terminal packets and said network encoded data packet;
wherein said network encoding comprises performing, by said relay station, multiplication transforming in the binary domain on at least one of multiple bit sequences obtained after performing channel decoding on said copies of multiple user terminal data packets received by said relay station, and then performing adding transforming processing in the binary domain with other bit sequences; or performing bitwise XOR or XNOR processing on the multiple bit sequences.

3. A method according to claim 2 , wherein said step of performing joint soft combining and decoding comprises the following steps:
B1. obtaining an initial soft information sequence of encoded bit sequence of said network encoded data packet and an estimated soft information sequence of an encoded bit sequence or an initial soft information sequence of the encoded bit sequence of said copies of multiple user terminal packets;
B2. performing joint soft combining processing on said initial soft information sequence of the encoded bit sequence of said network encoded data packet and said estimated soft information sequence of the encoded bit sequence or said initial soft information sequence of the encoded bit sequence of said copies of multiple user terminal packets, so as to obtain a soft combined bit likelihood ratio sequence of the bit sequence of at least one user terminal data packet of said multiple user terminal data packets;
B3. performing channel decoding on said soft combined bit likelihood ratio sequence.

4. A method according to claim 3 , wherein said network encoding comprises performing bitwise XOR processing on multiple bit sequence obtained after performing channel decoding on said copies of multiple user terminal data packets, said step B2 comprises the following step:
performing soft combining processing according to equation

L
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L
~

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R
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(

b
1

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=

L
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L
^

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R
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(

b
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+

log
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∑
oddc

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ⅇ

LLR
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(
oddc
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∑
evenc

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LLR
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(
evenc
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,

wherein b 1 is an encoded bit in a user terminal data packet, L{tilde over (L)}R(b 1 ) is the soft combined bit likelihood ratio after performing soft combining on the encoded bit, L{circumflex over (L)}R(b 1 ) is an estimated bit likelihood ratio of the encoded bit, LLR(oddc) is a combination of an odd number of bit likelihood ratios out of estimated likelihood ratios L{circumflex over (L)}R(b 2 ), L{circumflex over (L)}R(b 3 ), L{circumflex over (L)}R(b m ) of corresponding encoded bits b 2 , b 3 , . . . b m of other user terminal data packets with which XOR processing is performed on the encoded bit b 1 and an initial bit likelihood ratio of corresponding encoded bit b NC in said network encoded data packet,

∑
oddc

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ⅇ

LLR
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(
oddc
)

is the sum of all e raised to the power of the combinations of an odd number of bit likelihood ratios combinations, b NC =b 1 ⊕b 2 ⊕ . . . ⊕b m , m is the number of the user terminals; LLR(evenc) is a combination of an even number of bit likelihood ratios out of estimated likelihood ratios L{circumflex over (L)}R(b 2 ), L{circumflex over (L)}R(b 3 ), L{circumflex over (L)}R(b m ) of corresponding encoded bits b 2 , b 3 , . . . b m of the other user terminal data packets with which XOR processing is performed on the encoded bit b 1 and the initial bit likelihood ratio of the corresponding encoded bit b NC in said network encoded data packet,

∑
evenc

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ⅇ

LLR
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(
evenc
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is the sum of all e raised to the power of the

Assignees

• Li Ji
• Wang Yonggang
• Hu Zhongji
• Alcatel Lucent

Inventors

• Li Ji
• Wang Yonggang
• Hu Zhongji

Classifications

• H04L1/06

  using space diversity · CPC title

• H04L1/0076

  Distributed coding, e.g. network coding, involving channel coding (coding in both space and time H04L1/0618; cooperative diversity H04B7/022) · CPC title

• H04L2001/0097

  Relays · CPC title

• H04W88/04 Primary

  adapted for relaying to or from another terminal or user · CPC title

• H04L1/0045

  Arrangements at the receiver end · CPC title