WIRELESS RELAY APPARATUS, WIRELESS RECEIVING APPARATUS, AND DECODING METHOD

• US 20120102378A1
• Filed: 04/22/2011
• Published: 04/26/2012
• Est. Priority Date: 10/24/2008
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: AOKI, Tsuguhide, TANABE, Yasuhiko, MATSUMOTO, Tadashi
• Granted Patent: US 8,924,813 B2
• Time in Patent Office: Days
• US Class Current: 714/752
• CPC Class Codes: H03M 13/2792 Interleaver wherein interleaving is performed jointly with another technique such as puncturing, multiplexing or routing
• CPC Class Codes: H03M 13/2957 Turbo codes and decoding
• CPC Class Codes: H04B 7/155 Ground-based stations H04B7/204 takes precedence
• CPC Class Codes: H04L 1/0045 Arrangements at the receiver end
• CPC Class Codes: H04L 1/005 Iterative decoding, including iteration between signal detection and decoding operation
• CPC Class Codes: H04L 2001/0097 Relays

Abstract

In one embodiment, a wireless relay apparatus for replaying a signal processed by first encoding from a transmitting apparatus to a receiving apparatus is disclosed. The apparatus includes a demodulation unit, a decoding unit, a detection unit, an extraction unit, and an encoding unit. The demodulation unit demodulates a received signal. The decoding unit performs error correction decoding corresponding to the first encoding on the demodulated signal. The detection unit detects an error in a decoded signal. The extraction unit extracts a portion pertaining to information data from the demodulated signal by hard decision, if the detection unit detects an error. The encoding unit performs error correcting coding on the extracted portion pertaining to the information data with an error. The information data encoded by the encoding unit is transmitted.

Claims

1. A wireless relay apparatus for relaying a signal processed by a first encoding from a transmitting apparatus to a receiving apparatus, comprising:

a demodulation unit configured to demodulate a received signal;

a decoding unit configured to perform error correction decoding corresponding to the first encoding on the demodulated signal;

a detection unit configured to detect an error in a decoded signal;

an extraction unit configured to extract a portion pertaining to information data from the demodulated signal by hard decision, if the detection unit detects an error; and

an encoding unit configured to perform error correcting coding on the extracted portion pertaining to the information data with an error,

wherein the information data encoded by the encoding unit is transmitted.

2. The apparatus according to claim 1, wherein the encoding unit comprises:

an interleaver unit configured to rearrange the data; and

an encoder unit configured to encode the rearranged data.

3. The apparatus according to claim 1, further comprising an error estimation unit configured to estimate an error rate of the received signal, and

wherein the receiving apparatus is notified of the error rate.

4. The apparatus according to claim 1, further comprising a decoding unit configured to decode the received signal containing an error, and

wherein the extraction unit extracts the information data from the decoded signal.

5. The apparatus according to claim 4, further comprising an error rate calculation unit configured to calculate an error rate of the received signal containing an error using an external value, and

wherein the receiving apparatus is notified of the error rate.

11. The apparatus according to claim 1, wherein the information data includes more than one bit error.

6. A wireless receiving apparatus comprising:

a first decoding unit configured to perform a first decoding process of calculating a first a posteriori value using a first a priori value and a first received signal as a received signal of a first frame transmitted from a transmitting apparatus, and output a hard decision value of the first a posteriori value and a first external value;

a second decoding unit configured to perform a second decoding process of calculating a second a posteriori value using a second a priori value and a second received signal as a received signal of a second frame transmitted from a relay apparatus having received the first frame and containing re-encoded information data containing an error, and output a hard decision value of the second a posteriori value and a second external value;

a first a priori value calculation unit configured to calculate the second a priori value by correcting the first external value based on an error rate of one of the first frame and the second frame; and

a second a priori value calculation unit configured to calculate the first a priori value by correcting the second external value based on the error rate.

7. The apparatus according to claim 6, further comprising an interleaver unit configured to perform a first interleaving process on the first external value,

wherein the first a priori value calculation unit calculates the second a priori value by correcting the first external value having undergone the first interleaving process, based on the error rate of one of the first frame and the second frame,

further comprising a deinterleaver unit configured to perform, on the second external value, a deinterleaving process of performing rearrangement in an order opposite to that of the first interleaving process, and

wherein the second a priori value calculation unit calculates the first a priori value by correcting the second external value having undergone the deinterleaving process, based on the error rate.

8. The apparatus according to claim 7, wherein the second frame has undergone a second interleaving process of performing the same rearrangement as that of the first interleaving process.

9. The apparatus according to claim 6, further comprising an error rate calculation unit configured to calculate the error rate which changes from one bit to another using the second external value.

10. The apparatus according to claim 6, wherein the error rate is an error rate of the first frame notified from the relay apparatus.