Channel estimation apparatus and method

Patent metadata

Field	Value
Publication number	US-10284272-B2
Application number	US-201615258943-A
Country	US
Kind code	B2
Filing date	Sep 7, 2016
Priority date	Apr 10, 2014
Publication date	May 7, 2019
Grant date	May 7, 2019

Abstract

A channel estimation apparatus and method are provided to ensure that a channel estimation value can correctly reflect a transmission channel status, so that an orthogonal frequency division multiplexing (OFDM)-based wireless system can correctly transmit an aggregate long frame according to the channel estimation value. The channel estimation apparatus determines a first channel estimation value, receives a first symbol group of a long frame according to the first channel estimation value, and determines a second channel estimation value according to the first symbol group, and if a difference between the first channel estimation value and the second channel estimation value is less than or equal to a first threshold, determines a third channel estimation value according to the first channel estimation value and the second channel estimation value.

First claim

What is claimed is:

1. A channel estimation apparatus, comprising:
a processor;
a processing unit coupled to the processor, configured to cause the processor to determine a first channel estimation value; and
an obtaining unit coupled to the processor, configured to cause the processor to receive a first symbol group of a long frame according to the first channel estimation value obtained by the processing unit, wherein the long frame comprises at least two symbol groups, and each symbol group comprises at least one data symbol, wherein
the processing unit is further configured to cause the processor to:
determine a second channel estimation value according to the first symbol group obtained by the obtaining unit;
if a difference between the first channel estimation value and the second channel estimation value is less than or equal to a first threshold, determine a third channel estimation value according to the first channel estimation value and the second channel estimation value;
determine a transmission status of a data transmission channel based on the third channel estimation value so that the long frame can be correctly transmitted.

2. The apparatus according to claim 1 , wherein the obtaining unit is further configured to obtain a data packet header of the long frame before the first channel estimation value is determined; and
the processing unit is further configured to determine the first channel estimation value according to the data packet header obtained by the obtaining unit.

3. The apparatus according to claim 1 , wherein the processing unit is further configured to determine the third channel estimation value according to a first formula, wherein
the first formula is H3=a*H1+(1−a)*H2, wherein
“H1” is the first channel estimation value, “H2” is the second channel estimation value, “H3” is the third channel estimation value, and “a” is a weight of the first channel estimation.

4. The apparatus according to claim 3 , wherein the processing unit is further configured to determine the weight according to a second formula before determining the third channel estimation value according to the first formula, wherein
the second formula is a=(s+1)/(s+2), wherein “s” is a data symbol sequence number, in the long frame, of the last data symbol in the first symbol group.

5. The apparatus according to claim 1 , wherein the obtaining unit is further configured to obtain a check code corresponding to the first symbol group; and
the processing unit is further configured to check the first symbol group according to the check code obtained by the obtaining unit.

6. The apparatus according to claim 5 , wherein the obtaining unit is specifically configured to obtain, using a phase shift, the check code corresponding to the first symbol group.

7. A channel estimation method, comprising:
determining a first channel estimation value;
receiving a first symbol group of a long frame according to the first channel estimation value, wherein the long frame comprises at least two symbol groups and each symbol group comprises at least one data symbol;
determining a second channel estimation value according to the first symbol group;
if a difference between the first channel estimation value and the second channel estimation value is less than or equal to a first threshold, determining a third channel estimation value according to the first channel estimation value and the second channel estimation value; and
determining a transmission status of a data transmission channel based on the third channel estimation value so that the long frame can be correctly transmitted.

8. The method according to claim 7 , wherein before determining the first channel estimation value, the method further comprises:
obtaining a data packet header of the long frame; and wherein
determining, by the channel estimation apparatus, the first channel estimation value comprises:
determining the first channel estimation value according to the data packet header.

9. The method according to claim 7 , wherein determining the third channel estimation value according to the first channel estimation value and the second channel estimation value comprises:
determining the third channel estimation value according to a first formula, wherein
the first formula is H3=a*H1+(1−a)*H2, wherein
“H1” is the first channel estimation value, “H2” is the second channel estimation value, “H3” is the third channel estimation value, and “a” is a weight used during calculation.

10. The method according to claim 9 , wherein before determining the third channel estimation value according to the first formula, the method further comprises determining the weight according to a second formula, wherein
the second formula is a=(s+1)/(s+2), wherein “s” is a data symbol sequence number, in the long frame, of the last data symbol in the first symbol group.

11. The method according to claim 7 , wherein before determining the second channel estimation value according to the first symbol group, the method further comprises:
obtaining a check code corresponding to the first symbol group, and checking the first symbol group according to the check code.

12. The method according to claim 11 , wherein obtaining the check code corresponding to the first symbol group comprises:
obtaining, using a phase shift, the check code corresponding to the first symbol group.

13. A non-transitory machine readable medium having instructions stored therein, which when executed by a processor, cause the processor to perform operations, the operations include;
determining a first channel estimation value;
receiving a first symbol group of a long frame according to the first channel estimation value, wherein the long frame comprises at least two symbol groups, and each symbol group comprises at least one data symbol;
determining a second channel estimation value according to the first symbol group;
if a difference between the first channel estimation value and the second channel estimation value is less than or equal to a first threshold, determining a third channel estimation value according to the first channel estimation value and the second channel estimation value; and
determining a transmission status of a data transmission channel based on the third channel estimation value so that the long frame can be correctly transmitted.

14. The non-transitory machine readable medium of claim 13 , wherein before determining the first channel estimation value, further comprises:
obtaining a data packet header of the long frame; and
determining the first channel estimation value according to the data packet header.

15. The non-transitory machine readable medium of claim 13 , wherein determining the third channel estimation value according to the first channel estimation value and the second channel estimation value comprises:
determining the third channel estimation value according to a first formula, wherein
the first formula is H3=a*H1+(1−a)*H2, wherein
“H1” is the first channel estimation value, “H2” is the second channel estimation value, “H3” is the third channel estimation value, and “a” is a weight used during calculation.

16. The non-transitory machine readable medium of claim 15 , wherein before determining the third channel estimation value according to the first formula, further comprises determining the weight according to a second formula, wherein
the second formula is a=(s+1)/(s+2), wherein “s” is a data symbol sequence number, in the long frame, of the last data symbol in the first symbol group.

17. The non-transitory

Assignees

• Huawei Tech Co Ltd

Inventors

• Yan Min
• Zhang Junping
• Wang Wei
• Zhang Qian

Classifications

• H04L27/2601

  Multicarrier modulation systems · CPC title

• H04L27/2602

  Signal structure · CPC title

• H04L43/16

  Threshold monitoring · CPC title

• H04L69/22

  Parsing or analysis of headers · CPC title

• H04L25/0202 Primary

  Channel estimation · CPC title