CA2391623C - Adaptive hybrid arq using turbo code structure - Google Patents
Adaptive hybrid arq using turbo code structure Download PDFInfo
- Publication number
- CA2391623C CA2391623C CA002391623A CA2391623A CA2391623C CA 2391623 C CA2391623 C CA 2391623C CA 002391623 A CA002391623 A CA 002391623A CA 2391623 A CA2391623 A CA 2391623A CA 2391623 C CA2391623 C CA 2391623C
- Authority
- CA
- Canada
- Prior art keywords
- bits
- received
- encoded
- encoded bits
- transmitting
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/12—Arrangements for detecting or preventing errors in the information received by using return channel
- H04L1/16—Arrangements for detecting or preventing errors in the information received by using return channel in which the return channel carries supervisory signals, e.g. repetition request signals
- H04L1/18—Automatic repetition systems, e.g. Van Duuren systems
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03M—CODING; DECODING; CODE CONVERSION IN GENERAL
- H03M13/00—Coding, decoding or code conversion, for error detection or error correction; Coding theory basic assumptions; Coding bounds; Error probability evaluation methods; Channel models; Simulation or testing of codes
- H03M13/63—Joint error correction and other techniques
- H03M13/6306—Error control coding in combination with Automatic Repeat reQuest [ARQ] and diversity transmission, e.g. coding schemes for the multiple transmission of the same information or the transmission of incremental redundancy
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/004—Arrangements for detecting or preventing errors in the information received by using forward error control
- H04L1/0041—Arrangements at the transmitter end
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/004—Arrangements for detecting or preventing errors in the information received by using forward error control
- H04L1/0045—Arrangements at the receiver end
- H04L1/0047—Decoding adapted to other signal detection operation
- H04L1/005—Iterative decoding, including iteration between signal detection and decoding operation
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/004—Arrangements for detecting or preventing errors in the information received by using forward error control
- H04L1/0056—Systems characterized by the type of code used
- H04L1/0064—Concatenated codes
- H04L1/0066—Parallel concatenated codes
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/12—Arrangements for detecting or preventing errors in the information received by using return channel
- H04L1/16—Arrangements for detecting or preventing errors in the information received by using return channel in which the return channel carries supervisory signals, e.g. repetition request signals
- H04L1/18—Automatic repetition systems, e.g. Van Duuren systems
- H04L1/1812—Hybrid protocols; Hybrid automatic repeat request [HARQ]
- H04L1/1819—Hybrid protocols; Hybrid automatic repeat request [HARQ] with retransmission of additional or different redundancy
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/12—Arrangements for detecting or preventing errors in the information received by using return channel
- H04L1/16—Arrangements for detecting or preventing errors in the information received by using return channel in which the return channel carries supervisory signals, e.g. repetition request signals
- H04L1/18—Automatic repetition systems, e.g. Van Duuren systems
- H04L1/1829—Arrangements specially adapted for the receiver end
- H04L1/1835—Buffer management
- H04L1/1845—Combining techniques, e.g. code combining
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03M—CODING; DECODING; CODE CONVERSION IN GENERAL
- H03M13/00—Coding, decoding or code conversion, for error detection or error correction; Coding theory basic assumptions; Coding bounds; Error probability evaluation methods; Channel models; Simulation or testing of codes
- H03M13/29—Coding, decoding or code conversion, for error detection or error correction; Coding theory basic assumptions; Coding bounds; Error probability evaluation methods; Channel models; Simulation or testing of codes combining two or more codes or code structures, e.g. product codes, generalised product codes, concatenated codes, inner and outer codes
- H03M13/2957—Turbo codes and decoding
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03M—CODING; DECODING; CODE CONVERSION IN GENERAL
- H03M13/00—Coding, decoding or code conversion, for error detection or error correction; Coding theory basic assumptions; Coding bounds; Error probability evaluation methods; Channel models; Simulation or testing of codes
- H03M13/35—Unequal or adaptive error protection, e.g. by providing a different level of protection according to significance of source information or by adapting the coding according to the change of transmission channel characteristics
- H03M13/353—Adaptation to the channel
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03M—CODING; DECODING; CODE CONVERSION IN GENERAL
- H03M13/00—Coding, decoding or code conversion, for error detection or error correction; Coding theory basic assumptions; Coding bounds; Error probability evaluation methods; Channel models; Simulation or testing of codes
- H03M13/37—Decoding methods or techniques, not specific to the particular type of coding provided for in groups H03M13/03 - H03M13/35
- H03M13/3761—Decoding methods or techniques, not specific to the particular type of coding provided for in groups H03M13/03 - H03M13/35 using code combining, i.e. using combining of codeword portions which may have been transmitted separately, e.g. Digital Fountain codes, Raptor codes or Luby Transform [LT] codes
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/12—Arrangements for detecting or preventing errors in the information received by using return channel
- H04L1/16—Arrangements for detecting or preventing errors in the information received by using return channel in which the return channel carries supervisory signals, e.g. repetition request signals
- H04L1/18—Automatic repetition systems, e.g. Van Duuren systems
- H04L1/1867—Arrangements specially adapted for the transmitter end
- H04L1/1874—Buffer management
Abstract
A generic structure of Hybrid ARQ using Turbo Codes is provided which requires the function of channel coding, redundancy selection, buffering and maximum-ratio diversity combining, channel decoding, error detection, and sending back an acknowledgement to the transmitter (Fig.3). The functions of channel coding and redundancy selection (Fig.1) are performed at the transmitter while the remaining functions are performed at the receiver.
The initial code rate can be explicitly communicated to the receiver or blindly detected.
The initial code rate can be explicitly communicated to the receiver or blindly detected.
Description
Adaptive Hybrid ARQ Using Turbo Code Structure Field of the Invention The present invention relates generally to communication systems and in particular, to adaptive hybrid ARQ using turbo code structure.
Background of the Invention Adaptive Modulation and Coding (AMC) gives the flexibility to match the modulation and forward error correction (FEC) coding scheme to the average channel conditions for each user. AMC promises a large increase in average data rate for users that have a favorable channel quality due to their proximity to the base site or other geographical advantage. Enhanced GSM systems using AMC offer data rates as high as 384 kbps compared 100 kbps without AMC. Likewise, 1.25 MHz CDMA systems can offer peak data rates as high as 5 Mbps through AMC, where 460 kbps was typical without AMC. AMC, however, does have a few drawbacks. AMC is sensitive to measurement error and delay. In order to select the appropriate modulation, the scheduler must be aware of the channel quality. Errors in the channel estimate will cause the scheduler to select the wrong data rate and either transmits at too high a power, wasting system capacity, or too low a power, raising the block error rate. Delay in reporting channel measurements also reduces the reliability of the channel quality estimate due to constantly varying mobile channel.
To overcome measurement delay, the frequency of the channel measurement reports may be increased, however, the measurement reports consume system capacity that otherwise might be used to carry data.
For these reasons, AMC is often used to provide a coarse data rate selection, perhaps based on a sub-optimum channel estimate as compared to a set of independent thresholds. Automatic Repeat request (ARQ) can be used in conjunction with AMC
to ensure data delivery by requesting retransmissions of erroneously received blocks. The retransmission request can be ACK or NACK based. AMC is improved with ARQ
because it can automatically adapt to instantaneous channel conditions. The combined AMC (or FEC) and ARQ design process is very complex, involving FEC performance in
Background of the Invention Adaptive Modulation and Coding (AMC) gives the flexibility to match the modulation and forward error correction (FEC) coding scheme to the average channel conditions for each user. AMC promises a large increase in average data rate for users that have a favorable channel quality due to their proximity to the base site or other geographical advantage. Enhanced GSM systems using AMC offer data rates as high as 384 kbps compared 100 kbps without AMC. Likewise, 1.25 MHz CDMA systems can offer peak data rates as high as 5 Mbps through AMC, where 460 kbps was typical without AMC. AMC, however, does have a few drawbacks. AMC is sensitive to measurement error and delay. In order to select the appropriate modulation, the scheduler must be aware of the channel quality. Errors in the channel estimate will cause the scheduler to select the wrong data rate and either transmits at too high a power, wasting system capacity, or too low a power, raising the block error rate. Delay in reporting channel measurements also reduces the reliability of the channel quality estimate due to constantly varying mobile channel.
To overcome measurement delay, the frequency of the channel measurement reports may be increased, however, the measurement reports consume system capacity that otherwise might be used to carry data.
For these reasons, AMC is often used to provide a coarse data rate selection, perhaps based on a sub-optimum channel estimate as compared to a set of independent thresholds. Automatic Repeat request (ARQ) can be used in conjunction with AMC
to ensure data delivery by requesting retransmissions of erroneously received blocks. The retransmission request can be ACK or NACK based. AMC is improved with ARQ
because it can automatically adapt to instantaneous channel conditions. The combined AMC (or FEC) and ARQ design process is very complex, involving FEC performance in
-2-the channel of interest as well as delay and implementation complexity constraints. Using FEC+ARQ together is known as a type I hybrid ARQ.
Even greater throughputs or error performance can be achieved with type II
hybrid ARQ. This scheme, designated Hybrid ARQ in the remainder, is similar to standard ARQ in that it repeats all blocks that have been received in error. However, Hybrid ARQ
improves on standard ARQ methods by saving and using failed transmission blocks at the receiver to increase the coding gain. The failed transmission blocks are jointly decoded with the current block in order to improve performance. The blocks that are sent by the transmitter are considered part of a larger code. Because additional parts of this code are sent only in response to the instantaneous channel conditions, Hybrid ARQ is also correctly known as Incremental Redundancy or Adaptive Hybrid ARQ.
There are several different flavors of Hybrid ARQ. The simplest flavor is code combining (also known as Chase combining), which simply repeats the first block for each transmission. The joint decoder is a block repetition decoder can be implemented as a block combiner, which can look like an equal gain combiner or max-ratio combiner, followed by a single block decoder. Because code combining is in effect a repetition coding scheme, it is correctly classified as a type II hybrid ARQ. Advantages of Chase combining compared to other Hybrid ARQ methods include smaller decoder complexity, smaller memory requirements, the ability to self decode every block before joint decoding, and not having to specify maximum number of transmission attempts.
However, Hybrid ARQ methods that provide more sophisticated coding methods over the blocks than the simple block repetition code may offer larger coding gains. Hybrid ARQ schemes can be designed such that the first L blocks form part of a larger code. Construction techniques are available for many types of codes, including Reed-Solomon codes, convolutional codes, and turbo codes The L code blocks may also be partially overlapping, with some symbol positions repeated in more than one block.
These positions can be treated with a symbol combiner similar to the block combiner.
After L transmissions, the blocks are repeated, with the old blocks either combined with or replaced by the new blocks.
A self decodable block is one that may be decoded by itself before joint decoding. Obviously, the first of the L blocks is always self decodable. If the first block is severely damaged in transmission, it is advantageous to have the other blocks self decodable as well. The term type III hybrid ARQ was used in S. Kallel, "Complementary punctured convolutional codes and their applications," IEEE Trans. Commun., June 1995, to refer to the class of Hybrid ARQ protocols in which all blocks are self decodable.
Even greater throughputs or error performance can be achieved with type II
hybrid ARQ. This scheme, designated Hybrid ARQ in the remainder, is similar to standard ARQ in that it repeats all blocks that have been received in error. However, Hybrid ARQ
improves on standard ARQ methods by saving and using failed transmission blocks at the receiver to increase the coding gain. The failed transmission blocks are jointly decoded with the current block in order to improve performance. The blocks that are sent by the transmitter are considered part of a larger code. Because additional parts of this code are sent only in response to the instantaneous channel conditions, Hybrid ARQ is also correctly known as Incremental Redundancy or Adaptive Hybrid ARQ.
There are several different flavors of Hybrid ARQ. The simplest flavor is code combining (also known as Chase combining), which simply repeats the first block for each transmission. The joint decoder is a block repetition decoder can be implemented as a block combiner, which can look like an equal gain combiner or max-ratio combiner, followed by a single block decoder. Because code combining is in effect a repetition coding scheme, it is correctly classified as a type II hybrid ARQ. Advantages of Chase combining compared to other Hybrid ARQ methods include smaller decoder complexity, smaller memory requirements, the ability to self decode every block before joint decoding, and not having to specify maximum number of transmission attempts.
However, Hybrid ARQ methods that provide more sophisticated coding methods over the blocks than the simple block repetition code may offer larger coding gains. Hybrid ARQ schemes can be designed such that the first L blocks form part of a larger code. Construction techniques are available for many types of codes, including Reed-Solomon codes, convolutional codes, and turbo codes The L code blocks may also be partially overlapping, with some symbol positions repeated in more than one block.
These positions can be treated with a symbol combiner similar to the block combiner.
After L transmissions, the blocks are repeated, with the old blocks either combined with or replaced by the new blocks.
A self decodable block is one that may be decoded by itself before joint decoding. Obviously, the first of the L blocks is always self decodable. If the first block is severely damaged in transmission, it is advantageous to have the other blocks self decodable as well. The term type III hybrid ARQ was used in S. Kallel, "Complementary punctured convolutional codes and their applications," IEEE Trans. Commun., June 1995, to refer to the class of Hybrid ARQ protocols in which all blocks are self decodable.
-3-Since, as stated in Siemens AG TSGRI#3(99)177, March 22-26 1999 types II and III are "minor variants of the same scheme", no special designation is required.
However, the use of the designation emphasizes the fact that either only the first block or all L blocks are self decodable, and that the self decodable schemes require special care to construct .
Hybrid ARQ improvements can greatly increase user throughputs, potentially doubling system capacity. In effect, Hybrid ARQ adapts to the channel by sending additional increments of redundancy, which increases the coding rate and effectively lowers the data rate to match the channel. Hybrid ARQ does not rely only on channel estimates but also relies on the errors signaled by the ARQ protocol. Hybrid ARQ is even more di~cult to design than FEC+ARQ, because of additional control, code construction, and decoder implementation issues. In addition, Hybrid ARQ also complicate the ARQ
protocol implementation.
Turbo codes, which provide error correction gains close to the theoretical Shannon limit, can be used in conjunction with hybrid ARQ. Several prior art approaches exist, including code combining, punctured turbo codes and a priori methods.
These methods, however, do not make the best possible use of the turbo code structure in fading channels. These methods do also not handle combining adaptive coding and modulation with hybrid ARQ.
Prior-art ARQs do not make the best use of the turbo code structure in fading channels. Additionally, retransmissions are the same size as the original transmission and the throughput cost for a second transmission is significant. Prior-art ARQs not have provisions for self decodable blocks other than the first block, without having all the blocks self decodable and the self decodable blocks must be at least the same size as the information packet.
Thus, there is a need for a turbo hybrid ARQ that does not suffer from these limitations of the prior art. The invention provides a turbo hybrid ARQ that contains self decodable blocks other than the first block, allows retransmissions of different sizes, and is better on fading channels.
Summary of the Invention The present invention seeks to overcome the disadvantages of the prior art associated with adaptive hybrid ARQ using turbo code structure.
According to the first aspect of the invention, a method for transmitting data packets is provided. The method comprises the steps of: receiving an incoming data packet; determining an initial turbo code rate based on a channel condition;
turbo encoding the data packet to produce encoded bits comprising a plurality of systematic bits and a plurality of parity bits; transmitting a first portion of the encoded bits based on the initial turbo code rate; determining if an acknowledgment has been received for the transmitted first portion; and based on the acknowledgment and the initial turbo code rate, transmitting a second portion of the encoded bits.
According to another aspect of the invention, a method for receiving data packets is provided. The method comprises the steps of: receiving a portion of an encoded data packet; determining the content of information and parity symbols in the received portion based on an initial code rate for a first received portion of the encoded data packet; self decoding the received portion; determining whether the self decoding successfully decoded the received portion; when the self decoding of the received portion is not successful, combining the received portion of the encoded data packet with a previously combined portion of the encoded data packet to produce a new combined portion; storing the new combined portion; joint turbo decoding the new combined portion to produce decoded bits; and acknowledging if no error is present in the decoded bits.
The "Summary of the Invention" does not necessarily disclose all the inventive features. The inventions may reside in a sub-combination of the disclosed features.
Brief Description of the Drawings FIG. 1 is a block diagram of a turbo encoder in accordance with the preferred embodiment of the present invention.
FIG. 2 is a flow chart showing adaptive hybrid ARQ in accordance with the preferred embodiment of the present invention.
However, the use of the designation emphasizes the fact that either only the first block or all L blocks are self decodable, and that the self decodable schemes require special care to construct .
Hybrid ARQ improvements can greatly increase user throughputs, potentially doubling system capacity. In effect, Hybrid ARQ adapts to the channel by sending additional increments of redundancy, which increases the coding rate and effectively lowers the data rate to match the channel. Hybrid ARQ does not rely only on channel estimates but also relies on the errors signaled by the ARQ protocol. Hybrid ARQ is even more di~cult to design than FEC+ARQ, because of additional control, code construction, and decoder implementation issues. In addition, Hybrid ARQ also complicate the ARQ
protocol implementation.
Turbo codes, which provide error correction gains close to the theoretical Shannon limit, can be used in conjunction with hybrid ARQ. Several prior art approaches exist, including code combining, punctured turbo codes and a priori methods.
These methods, however, do not make the best possible use of the turbo code structure in fading channels. These methods do also not handle combining adaptive coding and modulation with hybrid ARQ.
Prior-art ARQs do not make the best use of the turbo code structure in fading channels. Additionally, retransmissions are the same size as the original transmission and the throughput cost for a second transmission is significant. Prior-art ARQs not have provisions for self decodable blocks other than the first block, without having all the blocks self decodable and the self decodable blocks must be at least the same size as the information packet.
Thus, there is a need for a turbo hybrid ARQ that does not suffer from these limitations of the prior art. The invention provides a turbo hybrid ARQ that contains self decodable blocks other than the first block, allows retransmissions of different sizes, and is better on fading channels.
Summary of the Invention The present invention seeks to overcome the disadvantages of the prior art associated with adaptive hybrid ARQ using turbo code structure.
According to the first aspect of the invention, a method for transmitting data packets is provided. The method comprises the steps of: receiving an incoming data packet; determining an initial turbo code rate based on a channel condition;
turbo encoding the data packet to produce encoded bits comprising a plurality of systematic bits and a plurality of parity bits; transmitting a first portion of the encoded bits based on the initial turbo code rate; determining if an acknowledgment has been received for the transmitted first portion; and based on the acknowledgment and the initial turbo code rate, transmitting a second portion of the encoded bits.
According to another aspect of the invention, a method for receiving data packets is provided. The method comprises the steps of: receiving a portion of an encoded data packet; determining the content of information and parity symbols in the received portion based on an initial code rate for a first received portion of the encoded data packet; self decoding the received portion; determining whether the self decoding successfully decoded the received portion; when the self decoding of the received portion is not successful, combining the received portion of the encoded data packet with a previously combined portion of the encoded data packet to produce a new combined portion; storing the new combined portion; joint turbo decoding the new combined portion to produce decoded bits; and acknowledging if no error is present in the decoded bits.
The "Summary of the Invention" does not necessarily disclose all the inventive features. The inventions may reside in a sub-combination of the disclosed features.
Brief Description of the Drawings FIG. 1 is a block diagram of a turbo encoder in accordance with the preferred embodiment of the present invention.
FIG. 2 is a flow chart showing adaptive hybrid ARQ in accordance with the preferred embodiment of the present invention.
-4-FIG. 3 is a flow chart showing adaptive hybrid ARQ in accordance with the preferred embodiment of the present invention.
FIG. 4 an example of the transmission blocks used in the scheme along with the block transmission sequence for various selected initial turbo code rate.
Detailed Description of the Drawings The Turbo codes used in the proposed hybrid ARQ system consists of a parallel concatenation of two convolutional encoders as shown in FIG. 1. In a preferred embodiment, the encoders are identical R=1/2 systematic and recursive convolutional encoders. The overall code rate of the turbo code entering the puncturing circuit for the preferred embodiment is '/4. For an input stream, four output streams are formed: the input stream x itself, a parity stream produced by the first convolutional code y,, interleaved input stream x' and the second parity stream yz produced by the second convolutional code. The puncturing block after the encoder is used to form (for example) R=3/4, R=2/3 and R=1/2 codes by puncturing the parity bits. As an example, for R=1/2 codes alternate parity bits are sent over the channel (x~, y,l, xz, y2~, x3, y,2,....xN, y where N is the size of Turbo interleaves) In case of R=1/3 code the interleaved systematic bits (x') are not sent over the channel.
The proposed method is described below with the flowchart shown in FIG.s 2 and 3. FIG. 2, shows the generic structure of Hybrid ARQ using Turbo Codes which requires the function of a) channel coding, b) redundancy selection, c) buffering and max-ratio diversity combining, d) channel decoding, e) error detection and f) sending back an acknowledgement to the transmitter. As illustrated in FIG. 2, the functions (a) and (b) are performed at the transmitter while functions (c) to (f) are performed at the receiver. The initial code rate can be explicitly communicated to the receiver or blindly detected. FIG.
4 shows an example of the transmission blocks used in the scheme along with the block transmission sequence for various selected initial turbo code rate.
Finally, FIG. 3 shows a specific example of the proposed scheme with initial code rate chosen as 1.
1. The initial coding rate for hybrid ARQ is first chosen. The rate can be detected at the receiver using blind rate detection or explicit rate detection.
If C/I > A initial Turbo code rate = 1 where A is some preset threshold ~ Otherwise initial Turbo code rate = 3/0 (or'h if below another threshold B)
FIG. 4 an example of the transmission blocks used in the scheme along with the block transmission sequence for various selected initial turbo code rate.
Detailed Description of the Drawings The Turbo codes used in the proposed hybrid ARQ system consists of a parallel concatenation of two convolutional encoders as shown in FIG. 1. In a preferred embodiment, the encoders are identical R=1/2 systematic and recursive convolutional encoders. The overall code rate of the turbo code entering the puncturing circuit for the preferred embodiment is '/4. For an input stream, four output streams are formed: the input stream x itself, a parity stream produced by the first convolutional code y,, interleaved input stream x' and the second parity stream yz produced by the second convolutional code. The puncturing block after the encoder is used to form (for example) R=3/4, R=2/3 and R=1/2 codes by puncturing the parity bits. As an example, for R=1/2 codes alternate parity bits are sent over the channel (x~, y,l, xz, y2~, x3, y,2,....xN, y where N is the size of Turbo interleaves) In case of R=1/3 code the interleaved systematic bits (x') are not sent over the channel.
The proposed method is described below with the flowchart shown in FIG.s 2 and 3. FIG. 2, shows the generic structure of Hybrid ARQ using Turbo Codes which requires the function of a) channel coding, b) redundancy selection, c) buffering and max-ratio diversity combining, d) channel decoding, e) error detection and f) sending back an acknowledgement to the transmitter. As illustrated in FIG. 2, the functions (a) and (b) are performed at the transmitter while functions (c) to (f) are performed at the receiver. The initial code rate can be explicitly communicated to the receiver or blindly detected. FIG.
4 shows an example of the transmission blocks used in the scheme along with the block transmission sequence for various selected initial turbo code rate.
Finally, FIG. 3 shows a specific example of the proposed scheme with initial code rate chosen as 1.
1. The initial coding rate for hybrid ARQ is first chosen. The rate can be detected at the receiver using blind rate detection or explicit rate detection.
If C/I > A initial Turbo code rate = 1 where A is some preset threshold ~ Otherwise initial Turbo code rate = 3/0 (or'h if below another threshold B)
-5-2. Assuming the initial code rate = l, the following steps are performed 3. Encode entire packet using rate R=Il4 Turbo Code 4. Transmit systematic bits only 5. Decode systematic bits (X,, Xz,...., XN) using hard decision ~ if Packet Success, then done (send ACK) else weight each channel symbol by block SNR and store
6. Transmit the first set of alternating parity bits (Y11, Yzz, ...., Yzrr)
7. Decode using R=1/2 Turbo Code if Packet Success, then done (send ACK) ~ else weight each channel symbol by block SNR and store
8. Transmit the second set of alternating parity bits (Y,z, Yz,,...., Yzrr)
9. Decode using R=1/3 code if Packet Success, then done (send ACK) else weight each channel symbol by block SNR and store
10. Transmit the first set of alternating parity bits for the second time (Y", Yzz, ...., Yzrr)
11. Add symbol-wise to the stored first set of alternating parity bits ~ decode the result using a rate 1/3 code ~ if Packet Success, then done (send ACK) ~ else store the weighted combined block
12. Transmit the second set of alternating parity bits for the second time (Y,z, Yz,,...., YzN)
13. Add symbol-wise to the second set of alternating parity bits ~ decode the result using a rate 1/3 code ~ if Packet Success, then done (send ACK) ~ else store the weighted combined block
14. Transmit interleaved systematic bits (x')
15. Decode the result using R=1/4 code ~ if Packet Success, then done (send ACK) ~ else store the weighted block
16. Transmit the first set of alternating parity bits for the third time and so on
17. Iterate steps 9 to 16 X times.
If Packet Success send ACK
Otherwise drop the packet It may be noted that at step (15) one could either use weighted systematic bits combined with the previous block of systematic bits and decode it as a R=1/3 code or can use the interleaved systematic bits and decode it as a R=1/4 code. The exact decoding method can be predetermined or communicated to the receiver during call set up or using in-band signaling.
If Packet Success send ACK
Otherwise drop the packet It may be noted that at step (15) one could either use weighted systematic bits combined with the previous block of systematic bits and decode it as a R=1/3 code or can use the interleaved systematic bits and decode it as a R=1/4 code. The exact decoding method can be predetermined or communicated to the receiver during call set up or using in-band signaling.
Claims (19)
1. A method for transmitting data packets, the method comprising the steps of:
receiving an incoming data packet;
determining an initial turbo code rate based on a channel condition;
turbo encoding the data packet to produce encoded bits comprising a plurality of systematic bits and a plurality of parity bits;
transmitting a first portion of the encoded bits based on the initial turbo code rate;
determining if an acknowledgment has been received for the transmitted first portion;
and based on the acknowledgment and the initial turbo code rate, transmitting a second portion of the encoded bits.
receiving an incoming data packet;
determining an initial turbo code rate based on a channel condition;
turbo encoding the data packet to produce encoded bits comprising a plurality of systematic bits and a plurality of parity bits;
transmitting a first portion of the encoded bits based on the initial turbo code rate;
determining if an acknowledgment has been received for the transmitted first portion;
and based on the acknowledgment and the initial turbo code rate, transmitting a second portion of the encoded bits.
2. The method of claim 1 where the second portion of encoded bits is smaller than the first portion of encoded bits.
3. The method of claim 1 where the a plurality of systematic and a plurality of parity bits are stored.
4. The method of claim 1 where the channel condition used to determine the initial turbo code rate is a carrier-to-interference ratio.
5. The method of claim 1 where the channel conditions used to determine the initial turbo code rate are determined at a transmitting site.
6. The method of claim 1 where the channel conditions used to determine the initial turbo code rate are reported by a receiving site.
7. The method of claim 1 where the initial turbo code rate is N/M, with N=1,2,3..., M=1,2,3..., and N <= M.
8. The method of claim 1 further comprising the steps of:
determine if a second acknowledgment has been received for the transmitted second portion; and based on the second acknowledgment being received, transmitting a third portion of the encoded bits.
determine if a second acknowledgment has been received for the transmitted second portion; and based on the second acknowledgment being received, transmitting a third portion of the encoded bits.
9. The method of claim 8 further comprising the steps of:
determining if a third acknowledgment has been received for the transmitted third portion; and based on the third acknowledgment being received, transmitting a fourth portion of the encoded bits.
determining if a third acknowledgment has been received for the transmitted third portion; and based on the third acknowledgment being received, transmitting a fourth portion of the encoded bits.
10. The method of claim 1 wherein the step of transmitting the first portion of the encoded bits comprises the step of transmitting systematic encoded bits.
11. The method of claim 1 wherein the step of transmitting the first portion of the encoded bits comprises the step of transmitting systematic encoded bits and a portion of the parity bits.
12. The method of claim 1 where a subsequent portion of the encoded bits, but not all subsequent portions of the encoded bits, are self-decodable.
13. The method of claim 12 wherein the subsequent portion of the encoded bits includes interleaved systematic encoded bits.
14. The method of claim 12 wherein the subsequent portion of the encoded bits includes interleaved systematic encoded bits and a portion of the parity bits.
15. A method for receiving data packets, the method comprising the steps of:
receiving a portion of an encoded data packet;
determining the content of information and parity symbols in the received portion based on an initial code rate for a first received portion of the encoded data packet;
self decoding the received portion;
determining whether the self-decoding successfully decoded the received portion;
when the self decoding of the received portion is not successful, combining the received portion of the encoded data packet with a previously combined portion of the encoded data packet to produce a new combined portion;
storing the new combined portion;
joint turbo decoding the new combined portion to produce decoded bits; and acknowledging if no error is present in the decoded bits.
receiving a portion of an encoded data packet;
determining the content of information and parity symbols in the received portion based on an initial code rate for a first received portion of the encoded data packet;
self decoding the received portion;
determining whether the self-decoding successfully decoded the received portion;
when the self decoding of the received portion is not successful, combining the received portion of the encoded data packet with a previously combined portion of the encoded data packet to produce a new combined portion;
storing the new combined portion;
joint turbo decoding the new combined portion to produce decoded bits; and acknowledging if no error is present in the decoded bits.
16. The method of claim 15 where the received portion of the encoded data packet is weighted with a block signal to noise ratio (SNR) before combining.
17. The method of claim 15 where the combining step comprises symbol combining interleaved systematic symbols with systematic symbols.
18. The method of claim 15 where the combining step comprises symbol combining overlapping symbols and concatenating non-overlapping symbols of the received portion of the encoded packet with the previous combined portion.
19. The method of claim 15 where the combining step comprises replacing systematic symbols with interleaved systematic symbols.
Applications Claiming Priority (5)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US16607899P | 1999-11-17 | 1999-11-17 | |
| US60/166,078 | 1999-11-17 | ||
| US09/603,426 | 2000-06-26 | ||
| US09/603,426 US6308294B1 (en) | 1999-11-17 | 2000-06-26 | Adaptive hybrid ARQ using turbo code structure |
| PCT/US2000/030332 WO2001037433A1 (en) | 1999-11-17 | 2000-11-02 | Adaptive hybrid arq using turbo code structure |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2391623A1 CA2391623A1 (en) | 2001-05-25 |
| CA2391623C true CA2391623C (en) | 2006-01-03 |
Family
ID=26861959
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002391623A Expired - Lifetime CA2391623C (en) | 1999-11-17 | 2000-11-02 | Adaptive hybrid arq using turbo code structure |
Country Status (7)
| Country | Link |
|---|---|
| US (1) | US6308294B1 (en) |
| EP (1) | EP1247345A4 (en) |
| JP (1) | JP2003515268A (en) |
| KR (1) | KR100496216B1 (en) |
| BR (1) | BR0015558A (en) |
| CA (1) | CA2391623C (en) |
| WO (1) | WO2001037433A1 (en) |
Families Citing this family (90)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19736626C1 (en) * | 1997-08-22 | 1998-12-10 | Siemens Ag | Data transmission method in digital transmission system |
| EP1903709B1 (en) | 1997-10-21 | 2015-11-18 | Ciena Corporation | Remodulators for WDM optical communication systems |
| US6445717B1 (en) * | 1998-05-01 | 2002-09-03 | Niwot Networks, Inc. | System for recovering lost information in a data stream |
| US7243294B1 (en) * | 2000-01-13 | 2007-07-10 | California Institute Of Technology | Serial turbo trellis coded modulation using a serially concatenated coder |
| CA2397893C (en) | 2000-01-20 | 2011-05-03 | Nortel Networks Limited | Hybrid arq schemes with soft combining in variable rate packet data applications |
| KR100360251B1 (en) * | 2000-03-29 | 2002-11-08 | 엘지전자 주식회사 | Hand-off processing apparatus and mobile receiver for telecommunication system |
| US6542559B1 (en) | 2000-05-15 | 2003-04-01 | Qualcomm, Incorporated | Decoding method and apparatus |
| US6977888B1 (en) * | 2000-09-14 | 2005-12-20 | Telefonaktiebolaget L M Ericsson (Publ) | Hybrid ARQ for packet data transmission |
| JP2002111512A (en) * | 2000-09-29 | 2002-04-12 | Sony Corp | Decoding device and method, data-receiving device and method |
| AU758813B2 (en) * | 2000-10-21 | 2003-04-03 | Samsung Electronics Co., Ltd. | Transmitting packet data in mobile communications systems |
| WO2002033877A1 (en) * | 2000-10-21 | 2002-04-25 | Samsung Electronics Co., Ltd | Data transmitting/receiving method in harq data communication system |
| KR100525384B1 (en) * | 2000-10-31 | 2005-11-02 | 엘지전자 주식회사 | Method for controlling packet retransmission in mobile communication system |
| JP3464649B2 (en) * | 2000-12-27 | 2003-11-10 | 松下電器産業株式会社 | Transmission device, reception device, and communication method |
| KR100553072B1 (en) * | 2000-12-28 | 2006-02-15 | 엘지전자 주식회사 | Fast blind rate detection algorithm |
| US7394792B1 (en) | 2002-10-08 | 2008-07-01 | Urbain A. von der Embse | Multi-scale CDMA |
| US7558310B1 (en) | 2001-01-09 | 2009-07-07 | Urbain Alfred von der Embse | Multi-scale code division frequency/wavelet multiple access |
| KR100724921B1 (en) * | 2001-02-16 | 2007-06-04 | 삼성전자주식회사 | Code generating and decoding apparatus and method in communication system |
| DE10107703A1 (en) * | 2001-02-19 | 2002-08-29 | Siemens Ag | Method and device for data transmission according to a hybrid ARQ method |
| JP3394528B2 (en) * | 2001-03-19 | 2003-04-07 | 松下電器産業株式会社 | Packet transmission system and packet transmission method |
| KR100753500B1 (en) * | 2001-03-21 | 2007-08-31 | 엘지전자 주식회사 | Method for Link Adaptation using Hybrid Automatic Repeat Request in Reverse Link, System for the same |
| US6973611B2 (en) * | 2001-04-17 | 2005-12-06 | Texas Instruments Incorporated | Interleaved coder and method |
| GB0110125D0 (en) * | 2001-04-25 | 2001-06-20 | Koninkl Philips Electronics Nv | Radio communication system |
| US7631242B2 (en) * | 2001-06-22 | 2009-12-08 | Broadcom Corporation | System, method and computer program product for mitigating burst noise in a communications system |
| CA2421427A1 (en) * | 2001-07-12 | 2003-01-23 | Min-Goo Kim | Reverse transmission apparatus and method for improving transmission throughput in a data communication system |
| KR100763378B1 (en) * | 2001-07-27 | 2007-10-05 | 엘지전자 주식회사 | Method for transmitting/receiving using plurality of antennas, system for the same |
| KR100464346B1 (en) * | 2001-08-17 | 2005-01-03 | 삼성전자주식회사 | Transmission/reception apparatus and method for packet retransmission in a cdma mobile communication system |
| US6738370B2 (en) | 2001-08-22 | 2004-05-18 | Nokia Corporation | Method and apparatus implementing retransmission in a communication system providing H-ARQ |
| US20030039226A1 (en) * | 2001-08-24 | 2003-02-27 | Kwak Joseph A. | Physical layer automatic repeat request (ARQ) |
| AU2007200745B2 (en) * | 2001-08-24 | 2008-11-13 | Interdigital Technology Corporation | Method for physical layer automatic repeat request for a subscriber unit |
| EP1436701B1 (en) * | 2001-08-24 | 2011-09-28 | Interdigital Technology Corporation | Base station implementing a physical layer automatic repeat request |
| US7447967B2 (en) * | 2001-09-13 | 2008-11-04 | Texas Instruments Incorporated | MIMO hybrid-ARQ using basis hopping |
| US20030066004A1 (en) * | 2001-09-28 | 2003-04-03 | Rudrapatna Ashok N. | Harq techniques for multiple antenna systems |
| KR100557167B1 (en) * | 2001-11-02 | 2006-03-03 | 삼성전자주식회사 | Apparatus and method for transmitting/receiving of re-transmit in a mobile communication system |
| KR100566241B1 (en) | 2001-11-19 | 2006-03-29 | 삼성전자주식회사 | Apparatus and method for soft combining symbol in mobile communication system |
| US6700867B2 (en) * | 2001-12-20 | 2004-03-02 | Motorola, Inc. | Method and system for reduced memory hybrid automatic repeat request |
| US6915477B2 (en) * | 2001-12-28 | 2005-07-05 | Lucent Technologies Inc. | Delay sensitive adaptive quality control loop for rate adaptation |
| CN1494780A (en) * | 2002-01-15 | 2004-05-05 | 连宇通信有限公司 | Hybrid ARQ method based upon Turbo product code |
| SG107576A1 (en) | 2002-01-17 | 2004-12-29 | Oki Techno Ct Singapore Pte | Communication system employing turbo codes and a hybrid automatic repeat request scheme |
| SG107575A1 (en) * | 2002-01-17 | 2004-12-29 | Oki Techno Ct Singapore Pte | Communication systems with hybrid automatic repeat requests (harq) and rate matching |
| US8233501B2 (en) * | 2002-02-13 | 2012-07-31 | Interdigital Technology Corporation | Transport block set segmentation |
| US6975650B2 (en) | 2002-02-13 | 2005-12-13 | Interdigital Technology Corporation | Transport block set segmentation |
| US7287206B2 (en) | 2002-02-13 | 2007-10-23 | Interdigital Technology Corporation | Transport block set transmission using hybrid automatic repeat request |
| TW200943812A (en) * | 2002-02-19 | 2009-10-16 | Interdigital Tech Corp | Method and apparatus for providing biasing criteria for binary decisions for use in wireless communications to enhance protection |
| JP3490425B2 (en) * | 2002-03-14 | 2004-01-26 | 松下電器産業株式会社 | Receiving device and receiving method |
| WO2003096581A1 (en) * | 2002-05-10 | 2003-11-20 | Interdigital Technology Corporation | Method and apparatus for reducing transmission-link errors |
| US6901063B2 (en) * | 2002-05-13 | 2005-05-31 | Qualcomm, Incorporated | Data delivery in conjunction with a hybrid automatic retransmission mechanism in CDMA communication systems |
| US6747967B2 (en) * | 2002-05-14 | 2004-06-08 | Interdigital Technology Corporation | Method and system for computing the optimal slot to cell assignment in cellular systems employing time division duplex |
| KR100899736B1 (en) * | 2002-05-25 | 2009-05-27 | 삼성전자주식회사 | Wireless packet data channel receiver apparatus and method |
| US6631127B1 (en) * | 2002-05-29 | 2003-10-07 | Motorola, Inc, | Apparatus and method for dynamically selecting an ARQ method |
| KR100584170B1 (en) * | 2002-07-11 | 2006-06-02 | 재단법인서울대학교산학협력재단 | Turbo Coded Hybrid Automatic Repeat Request System And Error Detection Method |
| CN1561604A (en) * | 2002-07-15 | 2005-01-05 | 连宇通信有限公司 | Method and apparatus for hybrid error correction in mobile telecommunications |
| JP4532272B2 (en) * | 2002-08-19 | 2010-08-25 | クゥアルコム・インコーポレイテッド | Deboosting in the communication environment |
| US8209575B2 (en) * | 2002-08-28 | 2012-06-26 | Texas Instruments Incorporated | MIMO hybrid-ARQ using basis hopping |
| US7423976B2 (en) * | 2002-09-24 | 2008-09-09 | Interdigital Technology Corporation | Block error rate estimate reporting for target signal to interference ratio adjustment |
| KR100548315B1 (en) * | 2002-10-28 | 2006-02-02 | 엘지전자 주식회사 | Error correction method using turbo code |
| US7293217B2 (en) * | 2002-12-16 | 2007-11-06 | Interdigital Technology Corporation | Detection, avoidance and/or correction of problematic puncturing patterns in parity bit streams used when implementing turbo codes |
| US7254769B2 (en) | 2002-12-24 | 2007-08-07 | Electronics And Telecommunications Research Insitute | Encoding/decoding apparatus using low density parity check code |
| EP1447936A1 (en) * | 2003-02-11 | 2004-08-18 | Motorola Inc. | Data communication unit and method thereof for iterative decoding |
| KR100461544B1 (en) * | 2003-02-27 | 2004-12-18 | 한국전자통신연구원 | Rate Compatible Code using High Dimensional Product Codes |
| US7155655B2 (en) * | 2003-07-22 | 2006-12-26 | Telefonaktiebolaget Lm Ericsson (Publ) | Adaptive hybrid ARQ algorithms |
| US8908496B2 (en) * | 2003-09-09 | 2014-12-09 | Qualcomm Incorporated | Incremental redundancy transmission in a MIMO communication system |
| KR100989314B1 (en) * | 2004-04-09 | 2010-10-25 | 삼성전자주식회사 | display apparatus |
| JP4488810B2 (en) * | 2004-06-30 | 2010-06-23 | 富士通株式会社 | Communication system and reception method |
| JP4501566B2 (en) * | 2004-07-13 | 2010-07-14 | 富士通株式会社 | Wireless communication apparatus and mobile station |
| DE602005013987D1 (en) * | 2004-09-15 | 2009-05-28 | Nokia Siemens Networks Gmbh | DECODING METHOD |
| US7165204B2 (en) * | 2004-11-15 | 2007-01-16 | Motorola, Inc. | Multi-mode hybrid ARQ scheme |
| KR100656982B1 (en) | 2004-12-21 | 2006-12-13 | 한국전자통신연구원 | Apparatus and method for decoding of portable internet mobile system |
| US7831882B2 (en) | 2005-06-03 | 2010-11-09 | Rambus Inc. | Memory system with error detection and retry modes of operation |
| US9459960B2 (en) | 2005-06-03 | 2016-10-04 | Rambus Inc. | Controller device for use with electrically erasable programmable memory chip with error detection and retry modes of operation |
| US7562285B2 (en) | 2006-01-11 | 2009-07-14 | Rambus Inc. | Unidirectional error code transfer for a bidirectional data link |
| US20070271495A1 (en) * | 2006-05-18 | 2007-11-22 | Ian Shaeffer | System to detect and identify errors in control information, read data and/or write data |
| US8352805B2 (en) | 2006-05-18 | 2013-01-08 | Rambus Inc. | Memory error detection |
| US8904265B2 (en) * | 2007-05-02 | 2014-12-02 | Broadcom Corporation | Optimal period rate matching for turbo coding |
| JPWO2009001465A1 (en) * | 2007-06-28 | 2010-08-26 | パナソニック株式会社 | Transmission device, transmission method, reception device, and reception method |
| US8145970B2 (en) * | 2007-09-06 | 2012-03-27 | Broadcom Corporation | Data puncturing ensuring orthogonality within communication systems |
| WO2009057922A1 (en) * | 2007-10-29 | 2009-05-07 | Lg Electronics Inc. | Method of data transmission using harq |
| ES2519766T3 (en) | 2007-12-20 | 2014-11-07 | Optis Wireless Technology, Llc | Control channel signaling using a common signaling field for the transport format and the redundancy version |
| KR101387530B1 (en) * | 2007-12-28 | 2014-04-21 | 엘지전자 주식회사 | Method of resouce allocation for HARQ |
| US8064333B2 (en) * | 2008-03-11 | 2011-11-22 | Nec Laboratories America, Inc. | Systems and methods for adaptive hybrid automatic retransmission requests |
| JP5056947B2 (en) * | 2008-06-04 | 2012-10-24 | 富士通株式会社 | Information processing apparatus, data transmission apparatus, and data transfer method for data transmission apparatus |
| US7978626B1 (en) | 2009-01-13 | 2011-07-12 | Sprint Spectrum L.P. | Method and system for adaptive hybrid automatic repeat request protocols based on network conditions |
| US8369337B1 (en) | 2009-11-05 | 2013-02-05 | Sprint Spectrum L.P. | Methods and devices for assigning a wireless communication device to a wireless coverage area based on early termination gain |
| KR101907943B1 (en) * | 2012-01-31 | 2018-12-19 | 삼성전자주식회사 | Apparatus and method for transmitting/receiving data in a communication system |
| US9531504B1 (en) | 2014-03-27 | 2016-12-27 | Sprint Spectrum L.P. | Bundling acknowledgments based on signal quality |
| US9473973B1 (en) | 2014-05-19 | 2016-10-18 | Sprint Spectrum L.P. | Reducing transmission rates in data slots subject to bundled acknowledgments |
| US9531505B1 (en) | 2014-06-20 | 2016-12-27 | Sprint Spectrum L.P. | Determining an amount of hybrid ARQ transmissions based on a series of acknowledgments |
| US9445344B1 (en) | 2014-07-22 | 2016-09-13 | Sprint Spectrum L.P. | Preferentially assigning data slots subject to bundled acknowledgments to devices that support carrier aggregation |
| US9609651B1 (en) | 2015-01-08 | 2017-03-28 | Sprint Spectrum L.P. | Exchanging uplink and downlink carrier frequencies |
| US10021686B1 (en) | 2015-10-19 | 2018-07-10 | Sprint Spectrum L.P. | Scheduling traffic based on acknowledgment bundling |
| WO2019190866A1 (en) | 2018-03-26 | 2019-10-03 | Rambus Inc. | Command/address channel error detection |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5983384A (en) * | 1997-04-21 | 1999-11-09 | General Electric Company | Turbo-coding with staged data transmission and processing |
| US5978365A (en) * | 1998-07-07 | 1999-11-02 | Orbital Sciences Corporation | Communications system handoff operation combining turbo coding and soft handoff techniques |
-
2000
- 2000-06-26 US US09/603,426 patent/US6308294B1/en not_active Expired - Lifetime
- 2000-11-02 KR KR10-2002-7006373A patent/KR100496216B1/en active IP Right Grant
- 2000-11-02 WO PCT/US2000/030332 patent/WO2001037433A1/en active IP Right Grant
- 2000-11-02 EP EP00975565A patent/EP1247345A4/en not_active Ceased
- 2000-11-02 CA CA002391623A patent/CA2391623C/en not_active Expired - Lifetime
- 2000-11-02 BR BR0015558-6A patent/BR0015558A/en not_active Application Discontinuation
- 2000-11-02 JP JP2001537876A patent/JP2003515268A/en active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| KR100496216B1 (en) | 2005-06-21 |
| EP1247345A1 (en) | 2002-10-09 |
| EP1247345A4 (en) | 2005-06-22 |
| KR20020068351A (en) | 2002-08-27 |
| BR0015558A (en) | 2002-07-09 |
| CA2391623A1 (en) | 2001-05-25 |
| JP2003515268A (en) | 2003-04-22 |
| WO2001037433A1 (en) | 2001-05-25 |
| US6308294B1 (en) | 2001-10-23 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA2391623C (en) | Adaptive hybrid arq using turbo code structure | |
| RU2236091C2 (en) | Method for data transmission/reception in data transfer system using hybrid automatic repetition request | |
| US6977888B1 (en) | Hybrid ARQ for packet data transmission | |
| CA2197131C (en) | Adaptive hybrid arq coding schemes for slow fading channels in mobile radio systems | |
| JP3910770B2 (en) | Error control method and receiver using the method | |
| FI105734B (en) | Automatic retransmission | |
| US7234095B2 (en) | Turbo encoded hybrid automatic repeat request system and error detection method | |
| TWI387247B (en) | Fec code and code rate selection based on packet size | |
| US7500166B2 (en) | Data receiving apparatus and hybrid-ARQ communication system | |
| EP1484853B1 (en) | Reception device and reception method | |
| JP3476807B2 (en) | Apparatus and method for transmitting data in data communication system using combined retransmission scheme | |
| US8234557B2 (en) | Transmission device | |
| US8074138B2 (en) | Decoding apparatus and method thereof | |
| US20050149841A1 (en) | Channel coding/decoding apparatus and method using a parallel concatenated low density parity check code | |
| KR20060079182A (en) | Adaptive hybrid arq algorithms | |
| US11387936B2 (en) | Hybrid automatic repeat request (HARQ) retransmission schemes for a wireless local area network (WLAN) | |
| US7178089B1 (en) | Two stage date packet processing scheme | |
| EP1711926A2 (en) | Adaptive rate code combining automatic repeat request (arq) communications method and system | |
| KR100403085B1 (en) | Ratematching algorithm for hybrid automatic repeat request system | |
| CN113366785B (en) | Communication transmitter for retransmitting MAC Protocol Data Units (MPDUs) | |
| EP2075972A1 (en) | Transmitter | |
| Joe | A novel adaptive hybrid ARQ scheme for wireless ATM networks | |
| JP2005051714A (en) | Packet transmission method and communication device | |
| WO2024061695A1 (en) | Communication devices and methods | |
| WO2003061181A1 (en) | Hybrid arq method based upon product code |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| MKEX | Expiry |
Effective date: 20201102 |