阅读说明：本技术 统一的纠错和检错码生成器 (Unified error correction and detection code generator ) 是由 K·S·贾亚思格赫 陈宇 杜冬阳 陈捷 于 2017-05-04 设计创作，主要内容包括：提供了一种方法,该方法包括：如果K个信息位被顺序地输入到包括J个寄存器的生成部件中,则生成J个附加位；在K个信息位中的至少一个信息位已经被输入到生成部件中之后,并且在K个信息位被输入到生成部件中之前,从J个寄存器中取回J*个附加位；构造包括K个信息位、J个附加位和J*个附加位中的每个位的码块,其中K个信息位、J个附加位和J*个附加位中的每个位在码块的相应的预定位置处；对码块进行极化编码。(There is provided a method comprising: if K information bits are sequentially input into a generation section including J registers, J additional bits are generated; retrieving J x additional bits from the J registers after at least one of the K information bits has been input into the generating means and before the K information bits are input into the generating means; constructing a code block including each of K information bits, J additional bits, and J additional bits, wherein each of the K information bits, J additional bits, and J additional bits is at a respective predetermined position of the code block; the code block is polarization encoded.)

1. An apparatus, comprising:

a generation component comprising J registers and configured to: generating J additional bits if K information bits are sequentially input into the generating means;

a retrieval member configured to: retrieving J additional bits from the J registers after at least one of the K information bits has been input into the generating means and before the K information bits are input into the generating means;

a construction component configured to: constructing a code block including each of the K information bits, the J additional bits, and the J additional bits, wherein each of the K information bits, the J additional bits, and the J additional bits is at a respective predetermined location of the code block;

an encoding component configured to: the code block is polarization encoded.

2. The apparatus of claim 1, wherein the retrieval member is configured to: retrieving each of the J x additional bits from a respective predetermined register after a respective predetermined input number of the K information bits is input into the generating means, wherein each of the predetermined input number is less than K.

3. The apparatus of claim 2, wherein the respective predetermined register is the same for all of the J x additional bits.

4. The apparatus of claim 2, wherein the respective predetermined number of inputs is the same for all of the J x additional bits.

5. The apparatus of any one of claims 1 to 4, wherein the J additional bits and each of the J additional bits are based on a different subset of the K information bits.

6. The apparatus of any one of claims 1 to 5, wherein:

the retrieval member is configured to: retrieving the J additional bits and each of the J x additional bits such that it is generated based on at least a predetermined number of information bits, wherein the predetermined number is equal to or greater than 2.

7. The apparatus of any one of claims 1 to 6, wherein:

one of the J additional bits is based on m information bits;

m < K; and is

The construction component is configured to: arranging the one of the J x additional bits immediately before, between, or immediately after a first information bit of the m information bits in the code block.

8. The apparatus of any one of claims 1 to 7, wherein the construction component comprises:

a replacement component configured to: permuting at least two of the J additional bits and the J x additional bits.

9. The apparatus according to any one of claims 1 to 8, wherein the J additional bits are error detection codes and the J additional bits are auxiliary bits.

10. The apparatus of any one of claims 1 to 9, wherein the generating means is a cyclic redundancy check generator and the J additional bits are a cyclic redundancy check code.

11. A method, comprising:

if K information bits are sequentially input into a generation section including J registers, J additional bits are generated;

retrieving J additional bits from the J registers after at least one of the K information bits has been input into the generating means and before the K information bits are input into the generating means;

constructing a code block including each of the K information bits, the J additional bits, and the J additional bits, wherein each of the K information bits, the J additional bits, and the J additional bits is at a respective predetermined location of the code block;

the code block is polarization encoded.

12. The method of claim 11, wherein the retrieving comprises: retrieving each of the J x additional bits from a respective predetermined register after a respective predetermined input number of the K information bits is input into the generating means, wherein each of the predetermined input number is less than K.

13. The method of claim 12, wherein the respective predetermined register is the same for all of the J x additional bits.

14. The method of claim 12, wherein the respective predetermined number of inputs is the same for all of the J x additional bits.

15. The method of any one of claims 11 to 14, wherein the J additional bits and each of the J additional bits are based on a different subset of the K information bits.

16. The method of any one of claims 11 to 15, wherein:

the retrieving includes: retrieving the J additional bits and each of the J x additional bits such that it is generated based on at least a predetermined number of information bits, wherein the predetermined number is equal to or greater than 2.

17. The method of any of claims 11 to 16, wherein:

one of the J additional bits is based on m information bits;

m < K; and is

The configuration includes: arranging the one of the J x additional bits immediately before, between, or immediately after a first information bit of the m information bits in the code block.

18. The method of any of claims 11-17, wherein the constructing comprises: permuting at least two of the J additional bits and the J x additional bits.

19. The method according to any one of claims 11 to 18, wherein the J additional bits are error detection codes and the J additional bits are auxiliary bits.

20. The method of any one of claims 11 to 19, wherein the generating means is a cyclic redundancy check generator and the J additional bits are a cyclic redundancy check code.

21. A computer program product comprising a set of instructions which, when executed on an apparatus, is configured to cause the apparatus to perform the method of any of claims 11 to 20.

22. The computer program product according to claim 21, embodied as a computer-readable medium or directly loadable into a computer.

Technical Field

The present invention extends to apparatus, methods and computer program products related to error detection.

Acronyms

3GPP 3 rd generation partnership project

5G 5 th generation

BLER Block error Rate

CRC cyclic redundancy check

DCI downlink control information

DL downlink

eMB enhanced mobile broadband

FAR false alarm rate

mMTC Large Scale MTC

MTC machine type communication

PC polarization encoding

RAN radio access network

RRC radio resource control

TX transmission/reception

UCI uplink control information

UL uplink

XOR exclusive OR

Background

The polar code proposed in [1] is decided for the 5G eMBB control channel and possibly also for mtc, since it has some advantages compared to other candidate coding schemes, e.g. low complexity, capacity implementation.

According to [2 ]]The polarization code is constructed based on the channel polarization principle. It refers to the fact that: a set of identical channels (i.e., many uses of the same channel in time) may be converted into a set of channels consisting of only nearly perfect channels or channels that are nearly useless. This conversion can be done in a simple recursive manner. For exampleTwo identical copies P of the binary input channel: x₁→Y₁Is converted into two new channels P₁：U₁→Y₁ ²And P₂：U₂→Y₁ ²U₁. Due to the fact thatIs a 1-to-1 transformation, thus subsequently derivingSome idea also shows that I (P)₁)≤I(P)≤I(P₂) I.e. P₁Is a worse channel than P, and P₂And more preferably. In this sense, the channel is polarized. The theory is through the pair P₁And P₂Etc. apply the same 2 by 2 transform to enhance polarization. Even further channel polarizations can be obtained by applying the process recursively to obtain N8, N16, N32, … … different channels. When N is large, bit channelOr becomes almost perfect (i.e.,) Or becomes almost useless (i.e.,). Furthermore, the fraction of the almost perfect bit channel is close to the channel capacity i (p).

From an encoding perspective, polar encoding involves combining data bits U_iPut in good bit channel position i and put fixed known bits in advance (similar to zero padding, e.g. U)_i0) is placed at the bad bit channel position i, also called the frozen bit. Thus, in polar code design, a key aspect is identifying the location of the data bits and the frozen bits.

The inventors have proposed a CRC distribution scheme for polar codes in which CRC bits are distributed within information bits to assist in polar decoding. This scheme is well-received and is considered a promising solution for polarization codes for eMBB control channels. Furthermore, it is listed as one of the alternatives in the conference protocol.

It was agreed in the 3GPP RAN 188 bis conference that the inventors will evaluate the following variants:

protocol:

j CRC bits are provided (which can be used for error detection, and also for auxiliary decoding and possibly for early termination)

J may differ in DL and UL

J may depend on the payload size in the UL (not excluding 0)

In addition, J' auxiliary bits are provided at the reliable sites (which can be used for auxiliary decoding and possibly for early termination)

·J+J’<Satisfies FAR target (n)_FAR) Number of bits required +6

-the working assumption:

for DL, n_FAR16 (at least for DCI related to eMBB)

For UL, n_FAR8 or 16 (at least for eMBB related UCI; note that this applies for UL with CRC case)

·J’>0

The working assumption: j "< ═ 2 additional auxiliary bits are provided at unreliable sites (which can be used for auxiliary decoding and possibly for early termination)

If significant benefit is shown from a larger J "value without undue complexity, it can be revised in RAN1# 89-encouraging companies to evaluate J" additionally 8

J' (and J ", if any) bits may be CRC bits and/or PC bits and/or hash bits (reducing range, if possible)

After studying the early termination technique, the placement of J, J' (and J ", if any) helper bits was further studied

-additional formula

-decentralized form

Uniformity

Unevenness

And additionally:

and (4) conclusion:

study up to RAN1#89 polar code construction techniques to facilitate early termination (i.e. before decoding all information bits) without degrading BLER performance or delay (especially considering the time for deinterleaving information and auxiliary bits) compared to purely implementation-based methods such as path metric based pruning

For example, the auxiliary bits are distributed in the codeword in such a way that: error detection may be performed after partial decoding

o investigating Performance, complexity and FAR impact

Nor does it exclude that studies use data-independent scrambling to facilitate early termination

Thus, in general, a total of J + J' + J "bits may be supported for error detection and correction. J' + J "═ J bits may also be referred to as auxiliary bits, which describe that these bits may be used to improve decoding performance, including decoding path pruning, early termination. From an implementation point of view, encoding and decoding become quite complex.

A straightforward implementation example is shown in fig. 1. The information bits are processed by a first module to generate J' auxiliary bits, and then by a second module to generate J "auxiliary bits, and then by a CRC module to generate J CRC bits. These modules are followed by a permutation module such that J' auxiliary bits are transmitted by the polar coding module on the reliable sub-channels and J "bits are transmitted on the unreliable sub-channels. The permutation module may also be used to distribute J CRC bits within the information bits to support early termination. If J ″, is 0, the second module may be omitted.

The scheme of fig. 1 requires three (for J ″ ═ 0) or four different modules to generate J + J ″ assist bits and J CRC bits. This is therefore rather complex and lacks flexibility, since J' and J "auxiliary bits can be used by the receiver depending on the decoding algorithm.

Although the CRC generator module is fairly mature, it requires two additional modules to generate J' and J "auxiliary bits. Since these auxiliary bits need to be placed on the reliable sub-channel and on the unreliable sub-channel, respectively, they are generated by different modules as a straightforward solution.

At the decoder side, the same process can be followed to make use of these auxiliary bits for tree pruning and error detection. Therefore, this makes encoding and decoding complicated, and may take longer processing time.

One can also generate the auxiliary bits as ordinary parity bits for the information bits in the normal order. It was thought that this method could achieve the same effect in a simpler manner.

The parity bits do not follow any particular order. Therefore, according to the inventors' view, they are useless in protecting blocks of information bits. The CRC is more suitable for correcting/detecting the information block. However, when a single CRC bit is compared to the first parity bit, it may appear the same. However, if more than one parity bit is considered, the other parity bits have no relationship to the previous parity bit or information bit. In contrast, CRC bits may cover overlapping sets of information bits.

Reference to the literature

[1]E.Ar1kan,“Channel polarization:a method for constructing capacity achieving codes for symmetric binary-input memoryless channels,”submitted forpublication,Oct.2007.

[2]3GPP Tdoc R1-164184,“Polar code design for NR”,Intel Corporation

Disclosure of Invention

The object of the present invention is to improve the prior art.

According to a first aspect of the present invention, there is provided an apparatus comprising: a generating unit including J registers and configured to generate J additional bits if K information bits are sequentially input into the generating unit; a retrieving means configured to retrieve J x additional bits from the J registers after at least one of the K information bits has been input into the generating means and before the K information bits are input into the generating means; a constructing means configured to construct a code block comprising each of the K information bits, the J additional bits, and the J additional bits, wherein each of the K information bits, the J additional bits, and the J additional bits is at a respective predetermined position of the code block; an encoding section configured to polarization-encode the code block.

The retrieval member may be configured to: after a respective predetermined input number of the K information bits is input into the generating means, each of the J x additional bits is retrieved from a respective predetermined register, wherein each of the predetermined input number is less than K.

The respective predetermined register may be the same for all J x additional bits.

The respective predetermined number of inputs may be the same for all J x additional bits.

The J additional bits and each of the J additional bits may be based on a different subset of the K information bits.

The retrieval member may be configured to: retrieving each of the J additional bits and the J x additional bits such that it is generated based on at least a predetermined number of information bits, wherein the predetermined number is equal to or greater than 2.

One additional bit of the J additional bits may be based on the m information bits; m < K; and the construction component may be configured to: the one of the J × additional bits is arranged immediately before, between, or immediately after a first information bit of the m information bits in the code block.

The construction component may include a permutation component configured to permute at least two of the J additional bits and J x additional bits.

The J additional bits may be an error detection code and the J additional bits may be auxiliary bits.

The generating means may be a cyclic redundancy check generator and the J additional bits may be a cyclic redundancy check code.

According to a second aspect of the invention, there is provided a method comprising: if K information bits are sequentially input into a generation section including J registers, J additional bits are generated; retrieving J x additional bits from the J registers after at least one of the K information bits has been input into the generating means and before the K information bits are input into the generating means; constructing a code block including each of K information bits, J additional bits, and J additional bits, wherein each of the K information bits, J additional bits, and J additional bits is at a respective predetermined position of the code block; the code block is polarization encoded.

The retrieving may include: after a respective predetermined input number of the K information bits is input into the generating means, each of the J x additional bits is retrieved from a respective predetermined register, wherein each of the predetermined input number is less than K.

The respective predetermined register may be the same for all J x additional bits.

The respective predetermined number of inputs may be the same for all J x additional bits.

The J additional bits and each of the J additional bits may be based on a different subset of the K information bits.

The retrieving may include: retrieving each of the J additional bits and the J x additional bits such that it is generated based on at least a predetermined number of information bits, wherein the predetermined number is equal to or greater than 2.

One additional bit of the J additional bits may be based on the m information bits; m < K; and the configuration may include: the one of the J × additional bits is arranged immediately before, between, or immediately after the first information bit of the m information bits in the code block.

The configuration may include: permuting at least two of the J additional bits and J x additional bits.

The J additional bits may be an error detection code and the J additional bits may be auxiliary bits.

The generating means may be a cyclic redundancy check generator and the J additional bits may be a cyclic redundancy check code.

The method may be a method of encoding.

According to a third aspect of the present invention, there is provided a computer program product comprising a set of instructions configured, when executed on an apparatus, to cause the apparatus to perform the method according to the second aspect. The computer program product may be embodied as a computer-readable medium or directly loadable into a computer.

According to some embodiments of the invention, at least one of the following advantages may be achieved:

only one error detection code generator is required;

no modification of the error detection code generator is required;

the computation of the error detection code and the auxiliary bits may require a minimum number of iterations;

flexibility in the design of the error detection code generator to meet further requirements (e.g. no restrictions on the choice of polynomial for the CRC generator caused by the generation of the auxiliary bits).

It will be understood that any of the above-described modifications may be applied to their respective aspects, individually or in combination, unless they are explicitly stated to exclude alternatives.

Drawings

Further details, features, objects and advantages will become apparent from the following detailed description of preferred embodiments of the invention, taken in conjunction with the accompanying drawings, in which:

fig. 1 shows an encoding unit;

FIG. 2 illustrates a CRC generator included in some embodiments of the invention;

FIG. 3 illustrates an additional bit generator used in variant 1 according to some embodiments of the invention;

FIG. 4 illustrates the principle of additional bit generation and placement of variant 2 according to some embodiments of the invention;

FIG. 5 illustrates an additional bit generator used in variation 3 according to some embodiments of the invention;

FIG. 6 illustrates the principle of additional bit generation and placement of variant 3 according to some embodiments of the invention;

FIG. 7 illustrates a graph of the sum x included in some embodiments of the invention³+x²+1 corresponding CRC generators;

FIG. 8 illustrates a CCITT CRC-16 generator included in some embodiments of the invention;

FIG. 9 shows an apparatus according to an embodiment of the invention;

FIG. 10 illustrates a method according to an embodiment of the invention; and

fig. 11 shows an apparatus according to an embodiment of the invention.

Detailed Description

Hereinafter, certain embodiments of the present invention are described in detail with reference to the drawings, in which features of the embodiments can be freely combined with each other unless otherwise described. It will be clearly understood, however, that the description of certain embodiments is given by way of example only and is in no way intended to limit the invention to the details disclosed.

Further, it will be understood that the apparatus is configured to perform the corresponding method, although in some cases only the apparatus or only the method is described.

According to some embodiments of the invention, a CRC generator is used to generate both J CRC bits and J' + J "bits for auxiliary polar decoding purposes. Hereinafter, these J + J' + J "bits may also be referred to as" additional bits ". J' or J "may be 0. The additional bits may be used for error detection and correction in the decoding of the information bits after polarization encoding.

According to some embodiments of the present invention, the CRC generator is used not only to generate J CRC bits, but also to generate J' and J ″ auxiliary bits. More precisely, a J-bit CRC generator is used to generate all the error detection and correction bits (additional bits). Some of these additional bits (including J CRC bits, J' + J "auxiliary bits) are obtained from the shift register when all information bits are input to the shift register (similar to conventional CRC generation), and some of these additional bits are generated from the corresponding intermediate values of the shift register, i.e. when only a part of the information bits are input to the CRC generator. Here, "intermediate output" or "intermediate value" means: the value of the corresponding register when at least one of the information bits is input into the CRC generator and before all the information bits of the information block are input into the CRC generator.

The concept of a CRC generator used in some embodiments of the present invention is illustrated in fig. 2. The information bits are sequentially input into the shift register. Between some of the shift registers there is a corresponding XOR operator, where the value of the preceding register is added to the value of the last register (feedback). At any time during the shift operation, the values in the register may be generated from a different number of information bits, and these values depend on the number of XOR operators and the consecutive register between the two XOR operators. "adding bits" means applying an XOR operation on these bits (i.e., ignoring overflow).

In the following, three variants of this concept are described.

Variant 1: all additional bits are generated on the fly and no permutation is used.

It is assumed that the subchannel indices of the polar encoder are ordered by their reliability { q0, q1, q2, …, qk }. The index going from high to low indicates reliability. Typically, the subchannels with high reliability are those at the end of the polar code input, and the unreliable subchannels are typically at the beginning, although some reliable and unreliable subchannels may be interleaved. The number of auxiliary bits to be generated, J' and J ", and the subchannels used for their transmission, may be obtained by some algorithm or based on a specification. Some examples are given later. Thus, the subchannel index for the J' auxiliary bits may be: { IR₀，IR₁，…，IR_J’-1And the index for the J "auxiliary bits is { IU }₀，IU₁，...，IU_J”-1In which IR is_iRepresents a reliable subchannel, and IU_iIndicating an unreliable subchannel. J CRC bits may follow the information bits and the (possibly interleaved) auxiliary bits.

Generating and placing additional bits into the "correct" sub-channel may proceed as follows: the subchannels are filled one after the other, substantially in parallel with inputting the information bits into the CRC generator. This is called "instant". If the subchannel index of the subchannel to be padded indicates that the subchannel carries information bits, the information bits are padded therein. If the subchannel index of the subchannel to be filled indicates that the subchannel carries an auxiliary bit of the type J', the value of one of the shift registers is fetched and filled in the corresponding subchannel. If the subchannel index of the subchannel to be filled indicates that the subchannel carries a supplemental bit of the type J', the value of one of the shift registers is fetched and filled in the corresponding subchannel.

Since the number of subchannels is greater than the number of information bits by the number of additional bits, in some embodiments, more than one subchannel is padded without inputting additional information bits into the CRC generator. For example, each time a subchannel is filled with additional bits, the filling may proceed to the next subchannel without inputting additional information bits. As another example, after every qth information bit, 2 subchannels may be padded without inputting additional information bits into the CRC generator. q may depend on the number of auxiliary bits (J' + J ═ J) and the number of information bits in the code block.

The shift registers used to generate J' + J ═ J × auxiliary bits may be different for different auxiliary bits. An example of such a register is one immediately following the XOR operator. Another example is to use a different register for the subsequent auxiliary bit. For example, where the register for the subsequent assist bit is the next register immediately after the previous register. This can be done in a cyclic manner if desired. Another example is that a fixed shift register (e.g., the first shift register) is used to generate all the auxiliary bits. When selecting the register for generating the auxiliary bits, duplication of information should be avoided, i.e. each of the auxiliary bits should be based on a different combination of information bits. Thus, in the last example (fixed shift register), at least one information bit should be input into the CRC register between two auxiliary bits.

When all information bits are passed into the CRC generator, the value of the shift register can be treated as J CRC bits.

In some embodiments, if the CRC bits are interleaved with the information bits, some or all of the J CRC bits may similarly be generated on-the-fly. That is, part or all of the J CRCs may not be obtained as the final value of the shift register when all the information bits are input. This may be very useful to meet early termination requirements. In this case, when all information bits are input into the CRC register, part or all of J' + J ═ J × auxiliary bits can be obtained.

Fig. 3 shows how the CRC generator of variant 1 generates J CRC bits, J' auxiliary bits and J ″ auxiliary bits.

Variant 2: all additional bits are generated instantaneously with a simple permutation.

Variant 2 is based on variant 1. As shown in fig. 4, the auxiliary bits are generated only after B information bits (B > 0) are input into the CRC generator. The auxiliary bits are generated in the same manner as in variation 1 by looking up the subchannel index. And then, in case there are K information bits to be transmitted in total, the first B information bits are transmitted after K-B information bits. The CRC bits, or a portion of the CRC bits, are transmitted after the first B information bits.

The benefit of this variant is that the auxiliary bits are generated when the shift register has sufficient feedback. That is, each XOR operation produces feedback, and thus the values of some of the shift registers are binary sums of a plurality of information bits. When there is sufficient feedback, one auxiliary bit can be tied to multiple information bits to provide better error correction and detection capabilities.

Variant 3: all additional bits are generated instantaneously with the true permutation.

In variant 3, similar to variants 1 and 2, both J' and J "auxiliary bits and CRC bits are generated by a CRC generator. Then, the permutation is performed to achieve better flexibility (see fig. 5). As shown in fig. 6, the first and second rows are generated on the fly based on K information bits, J' + J ═ J auxiliary bits, which may be interleaved between the information bits, and J CRC bits, which are appended. The bit sequence is then permuted. For example, as shown in the third row of fig. 6, some of the J CRC bits are also interleaved in the information bits. Therefore, only Jx (Jx < J) CRC bits are appended.

By permutation, additional operations and features may be supported:

some/all CRC bits may be transmitted forward to better support early termination.

The information bits associated with a particular CRC bit may be transmitted forward so that checks may be performed on that CRC bit in advance.

The information bits associated with the J' auxiliary bits transmitted on the reliable sub-channel may be placed on either the reliable sub-channel or the unreliable sub-channel to achieve better performance in terms of error detection and correction. If used for error detection, it was found that placing these auxiliary bits on the reliable sub-channels can achieve better performance.

The information bits associated with the J "auxiliary bits transmitted on the unreliable sub-channel may be placed on either the reliable sub-channel or the unreliable sub-channel to achieve better performance in terms of error detection and correction. If used for error correction, it was found that placing these auxiliary bits on the unreliable sub-channel could achieve better performance.

It is also possible to just place the relevant information bits before the auxiliary bits.

The greater flexibility of this variant also includes: the ratio of the number of relevant information bits to the number of auxiliary bits is controllable. The maximum number of information bits related to the auxiliary bits is determined by the number of feedbacks performed. The reason is that the mentioned feedback occurs when the number of input information bits exceeds the number of shift registers. Thus, with this scheme, any number of summed information bits based on the auxiliary bits to be generated can be obtained as long as there are information bits to be processed. An example of a shift register based CRC generator can be found in fig. 2.

It is also possible that the auxiliary bits are obtained simultaneously by a plurality of shift registers. When K is present₁、K₂、……、K_J’Personal informationWhen information bits are input into the CRC generator, where K₁、K₂、……、K_J’Is that>An integer of 0, or a value proportional to the information block size. One example of a special register is the register immediately following the XOR operator. Register and K₁、K₂、……、K_j’The value is selected to avoid repetition of the auxiliary bits. That is, the two auxiliary bits should not be based on the same combination of information bits.

As an example, the auxiliary bits may be selected such that the number of information bits involved in the XOR operation exceeds a particular threshold. As another example, the auxiliary bits may be fetched from the first J' or J "shift registers, or these registers starting from the register with the largest number of information bits involved in the XOR operation.

The receiver may use a CRC detector corresponding to the CRC generator. When the decoded information bits are input to it, the same auxiliary bits will be generated. In polar decoding, the receiver may compare the received auxiliary bit(s) with locally generated bit(s) to check if the path is correct. Paths that fail CRC bit checking will be given any real penalty. For example, the penalty value may be { 13515, ∞ }. The penalty is a value used to alter the path metric. The higher the penalty, the less reliable the path is considered to be. In a specific decoding step. A penalty may be given to the corresponding value to reduce its path metric. Paths with lower path metrics are more easily discarded during decoding.

The above-mentioned operations and parameters may be known by both the transmitter and the receiver (e.g., defined in the 3GPP specifications), or they may also be configured by signaling (e.g., RRC signaling) so that they are known by the transmitter and the receiver.

An example of J is 16 (16-bit CRC) for the downlink and 8 (8-bit CRC) for the uplink. J' may be 3 (3 auxiliary bits on the reliable channel) and J "may be 2 (2 bits on the unreliable channel).

In the following, two embodiments of the invention are explained in more detail.