KR20010009158A - Rate matching method for channelization code on up-link - Google Patents

Abstract

PURPOSE: A channelization code rate matching method is provided to accomplish optimal rate matching by realizing united puncturing algorithm to a channelization code such as a turbo code and a convolution code. CONSTITUTION: A channelization code rate matching method comprises performing channel coding to a transfer channel to output a plurality of bit streams by a code symbol unit, grouping and interleaving the bit streams by the code symbol unit so that uniform puncturing to the output bit streams is performed by the code symbol unit of a constant interval, and performing puncturing to the interleaved bit streams by the code symbol unit.

Description

Rate matching method for channelization code on up-link}

The present invention relates to a next generation communication system, and more particularly, to a channelization code rate matching method in uplink used to adjust channel symbol rate to an optimal level during coding and multiplexing procedures of a mobile communication system using a W-CDMA scheme. will be.

Recently, ARIB in Japan, ETSI in Europe, T1 in the US, TTA in Korea, and TTC in Japan are the core networks of the existing global system for mobile communications (GSM) that provide multimedia services such as voice, video and data. The next generation of mobile communication system based on wireless access technology was envisioned.

In order to present technical specifications for the next generation evolved mobile communication system, they agreed to joint research, and the project for this was called Third Generation Partnership Project (hereinafter abbreviated as 3GPP).

3GPP includes three major technical research areas.

The first is the 3GPP system and service sector, which is a study of the structure and service capabilities of the system based on the 3GPP specification.

Second, it is a research area for Universal Terrestrial Radio Access Network (UTRAN), where the Universal Terrestrial Radio Access Network (UTRAN) is based on W-CDMA according to Frequency Division Duplex (FDD) mode. Radio Access Network (RAN) using TD-CDMA according to Time Division Duplex (TDD) mode.

Third, it is a research section for core network that has evolved from the second generation mobile communication globalization system (GSM) and has third generation networking capability such as mobility management and global roaming.

In the above-mentioned technical research divisions of 3GPP, the research section for the global radio access network (UTRAN) describes the definition and description of the transport channel and the physical channel, in particular, the S1 series. S1.12 describes definitions and descriptions of multiplexing, channel coding, and interleaving according to frequency division duplex (FDD) mode.

1 is a diagram illustrating a coding and multiplexing procedure in an uplink according to a 3GPP radio access network (RAN) standard, and illustrates a coding and multiplexing procedure for a transport channel.

The data streams on the transport channel arrive at the coding / multiplexing blocks (1, 2) in the form of transport block sets. At this time, each transport block arrives through its own transport channel at regular time intervals.

In this case, a CRC bit for a cyclic redundancy check (hereinafter, referred to as CRC) is added to each transport block arriving at each coding / multiplexing block (1, 2) (S1), and then the same quality of service ( Transmission channels of Quality of Service (hereinafter referred to as QoS) are multiplexed (S2).

CRC is applied to error detection of a transport block, and a CRC bit is added to each transport block of all transport channels.

The multiplexed transmission channels of the same QoS are subjected to channel coding (S3), interleaving (S4), and rate matching (S5).

As the channel coding, either convolutional coding or turbo coding is used. In addition, specific coding may be used depending on a service.

In each coding / multiplexing block (1, 2), the transmission channels of different QoS adjusted to the optimal level of channel symbol rate by rate matching (S5) are multiplexed again, and then the data streams are respectively interleaved through the divided physical channels Is sent.

FIG. 2 is a diagram illustrating a coding and multiplexing procedure in a downlink according to the 3GPP radio access network (RAN) standard. Although the coding and multiplexing procedure for a transport channel in this downlink is similar to the uplink, rate matching (S13). It is different that inserting discontinuous transmission indication bits S14 and interleaving S15 are performed after the.

Even in this downlink, the data stream on the transport channel arrives at the coding / multiplexing blocks 10 and 20 in the form of transport block sets. At this time, each transport block arrives through its own transport channel at regular time intervals.

At this time, CRC bits for CRC are added to each transport block arriving at each coding / multiplexing block (10, 20) (S10), and then the transport channels of the same QoS are multiplexed (S11).

CRC is applied to error detection of a transport block, and a CRC bit is added to each transport block of all transport channels.

The multiplexed transmission channels of the same QoS are subjected to channel coding (S12), rate matching (S13), discontinuous transmission indication bit insertion (S14), and interleaving (S15).

As the channel coding, either convolutional coding or turbo coding is used. In addition, specific coding may be used depending on a service.

In each coding / multiplexing block (10,20), after adjusting to the optimal level of channel symbol rate by rate matching (S13), the transmission channels of different QoS which have undergone interleaving (S15) are multiplexed again, and then the data stream is divided Interleaved and transmitted through the physical channel.

Of note in the coding and multiplexing procedure in the uplink or downlink according to the 3GPP radio access network (RAN) standard is rate matching.

This rate matching is a process of adjusting the optimal channel symbol rate by applying repetition and puncturing for different transmission channels.

Currently, in the 3GPP radio access network (RAN) standard using the W-CDMA scheme, puncturing schemes for convolutional codes are considered in uplink and downlink, and puncturing schemes for turbo codes are Considered in the downlink.

Here, the purpose of the puncturing technique for the convolutional code is to distribute the positions of the punctured code bits as evenly as possible. A puncturing algorithm that can meet this goal can be easily implemented in the downlink. However, in the uplink, as described above, puncturing is performed on the interleaved bit strings, and thus additional conditions must be added to the puncturing conditions in the downlink to satisfy uniform puncturing in the code bit unit.

Currently, puncturing techniques for convolutional codes in the uplink have been continuously proposed in view of such a point.

As an example, the puncturing procedure for convolutional code in the downlink is very simple. This is because only the condition of puncturing the code bits uniformly needs to be satisfied.

Therefore, after the puncturing distance N is obtained for the entire bit string in the code bit unit, an algorithm for puncturing every Nth bit may be configured.

If the puncturing distance is '5', puncture the (5xn) th bits for the entire bit string for the convolutional code (where n = 1, 2, 3, ...).

However, if the puncturing distance is '5.5' rather than an integer, the puncturing procedure when the puncturing distance is '5' is performed for half of all bit strings, and the puncturing distance is '6' for the other half. Just execute the puncturing procedure at.

The puncturing technique for the turbo code is only considered in the downlink.

Unlike the convolutional code, the turbo code has different importance of each code bit. That is, in a turbo code having a specific code rate, systematic bit components are relatively important in the decoding process, and the remaining parity bits are excluded. Ingredients are less important.

Therefore, in the puncturing technique for the turbo code, puncturing for the systematic bit components should be excluded, and an algorithm for puncturing the remaining parity bit components is required.

All of the puncturing algorithms for turbo code in the downlink under consideration are basically punctured in code symbol units rather than code bits.

For example, one of the puncturing algorithms for turbo codes in the downlink proposed up to now is to puncture parity bit components alternately after determining the puncturing position of code symbols so that puncturing occurs uniformly in code symbol units. Algorithm The other is an algorithm that increases the location where puncturing can occur in code symbol units by a double distance and then punctures the parity bit components simultaneously for each code symbol where puncturing will occur.

The puncturing algorithm for the turbo code described so far is considered in the downlink, and the puncturing procedure in the downlink may be performed independently of the interleaving procedure since the puncturing procedure occurs in the interleaving front end.

However, since the rate matching procedure is performed after the interleaving in the uplink, there are additional considerations in performing the puncturing procedure for the turbo code.

In order to solve these additional matters, an optimal puncturing algorithm for the turbo code in the uplink has to be proposed, and such a puncturing technique for the turbo code has not been considered yet.

In addition, a rate matching method using an integrated puncturing algorithm for a convolution code and a turbo code, which is a channelization code in the uplink, which has been proposed so far, has not been proposed until now.

SUMMARY OF THE INVENTION An object of the present invention has been made in view of the above, and in the uplink using a puncturing algorithm for adjusting the channel symbol rate to an optimal level during the coding and multiplexing procedure of a mobile communication system using the W-CDMA scheme To provide an optimal rate matching method for the turbo code.

It is still another object of the present invention to provide an integrated puncturing algorithm for optimally adjusting channel symbol rates during coding and multiplexing procedures in a mobile communication system using a W-CDMA scheme. It is to provide an optimal rate matching method.

A feature of the channelization code rate matching method in the uplink according to the present invention for achieving the above object is, in the uplink of the mobile communication system using the channelization code, by performing channel coding for a transport channel a plurality of Outputting a bit string in units of code symbols, grouping and interleaving the bit strings in units of code symbols so that uniform puncturing occurs at regular intervals with respect to the output plurality of bit sequences; The puncturing is performed on the coded bits in units of code symbols at a predetermined interval.

Preferably, the puncturing step is performed in units of code symbols at intervals for the remaining bit strings used for decoding, except for a specific bit string output by the channel coding, wherein the puncturing is performed in the channel. In consideration of the importance of each bit string output by coding, puncturing for the specific bit string having a relatively high importance is excluded.

In the puncturing step, a uniform puncturing algorithm of a predetermined interval is applied to each of the interleaved bit strings.

Another feature of the present invention for achieving the above object is, in the uplink of a mobile communication system using a channelization code, a systematic bit component and one or more parity bit components as a result of channel coding for a transport channel. Outputting in parallel in units of symbols; interleaving the parity bit components with different priorities for each symbol unit output; and puncturing the interleaved parity bit components at predetermined intervals for each symbol unit. It consists of steps to perform.

Advantageously, a uniform number of puncturings occur for each column bit string after the puncturing step is interleaved.

In order to achieve the above object, a final feature of the present invention is to output a systematic bit component and one or more parity bit components in symbol units as a result of channel coding on a transmission channel of a mobile communication system, and The parity bit components are grouped and interleaved at different priority levels for each symbol unit to be output, and the puncturing of the parity bit components of each interleaving group is performed at predetermined intervals for each symbol unit.

1 is a diagram illustrating a coding and multiplexing procedure in the uplink according to the 3GPP Radio Access Network (RAN) standard.

2 is a diagram illustrating a coding and multiplexing procedure in downlink according to the 3GPP Radio Access Network (RAN) standard.

3 is a diagram illustrating a puncturing pattern when applying an optimized puncturing algorithm for a convolution code in uplink to a system using a turbo code.

4 is a view comparing an example of applying a puncturing algorithm for turbo code rate matching in uplink according to the present invention with an example of applying a puncturing algorithm in units of existing code symbols.

5 is a view showing a puncturing position for a turbo code in order to realize uniform puncturing in code symbol units according to the present invention.

FIG. 6 illustrates an actual puncturing pattern punctured in code symbol units for a turbo code in the present invention. FIG.

7 is a diagram illustrating an example of a sequence of serial bit strings output from the MIL interleaver when the number of columns of the interleaver K = 8.

8 illustrates puncturing positions in code symbol units for channelization codes in order to realize uniform puncturing in code symbol units according to the present invention.

FIG. 9 illustrates an actual puncturing pattern punctured in code symbol units for channelization codes in the present invention. FIG.

FIG. 10 illustrates a pattern in code symbol units for puncturing only a specific bit component (x) in a convolutional code to realize uniform puncturing in code symbol units according to the present invention. FIG.

FIG. 11 illustrates an actual puncturing pattern for puncturing only a specific bit component (x) in code symbol units in a convolutional code according to the present invention. FIG.

Hereinafter, a preferred embodiment of a channelization code rate matching method in uplink according to the present invention will be described with reference to the accompanying drawings.

In the present invention, the puncturing algorithm for the convolution code in the uplink is implemented to satisfy the following conditions.

First, make the positions of punctured code bits as evenly distributed as possible.

Second, the same number of code bits are punctured for each interleaved bit string. This is to allow uniform puncturing to occur even before the interleaved bit strings.

In the present invention, the puncturing algorithm for the turbo code in the uplink is implemented to satisfy the following conditions.

First, puncturing for systematic bit components is excluded.

Second, puncturing occurs evenly on all parity bit components with respect to the parity bit components.

Third, puncturing occurs uniformly over the entire bit string.

In addition to these three conditions, the present invention should consider one of the following conditions. This is because the rate matching procedure is performed on the bit streams interleaved in the uplink.

Fourth, the same puncturing should occur for all interleaved frames. In other words, an even code bit should be punctured for each of the serial bit strings that are the interleaved bit strings.

The present invention proposes a puncturing algorithm for the turbo code in the uplink that satisfies all the puncturing conditions for the turbo code, which is the channelization code.

In addition, the present invention proposes an integrated puncturing algorithm in the uplink that satisfies not only the convolution code, which is the channelization code, but also the puncturing condition for the turbo code.

The following describes a puncturing algorithm for the turbo code in the uplink according to the present invention.

Prior to the description, a system using a turbo code uses two turbo decoders, a MAP decoder, or a Viterbi decoder indicating a soft decision decoding output.

These two turbo decoders are located at both ends of the interleaver, and the code bits input to the first turbo decoder and the second turbo decoder are parity bit components.

Therefore, it is very important to adjust the transmission side so that uniform puncturing of the parity bit components occurs. It is also important to distribute the uniform puncturing for all channel coded bit streams.

Therefore, the present invention proposes a puncturing algorithm that satisfies the puncturing conditions for the turbo code in the uplink listed above.

3 illustrates a puncturing pattern when the optimized puncturing algorithm for the convolution code in the uplink is applied to a system using a turbo code. In FIG. 3, the code bits of the shaded portion are punctured.

3 is a case where the number of columns K of the interleaver is 8, where x is a systematic bit component, y is a first parity bit component, and z is a second parity bit component.

These bit components are those that are output as a result of channel coding for the transport channel, and the parity bit components are the output of each RSC coder (Recursive systematic convolutional coder).

As can be seen in FIG. 3, puncturing occurs for the systematic bit component, and puncturing occurs only for the second parity bit component z among the parity bit components.

This satisfies the uniform puncturing condition for the entire bitstream, the same puncturing condition for all interleaved frames, but excludes the puncturing condition for the systematic bit component, and for each parity bit component. It does not satisfy the uniform puncturing condition.

In contrast, the present invention proposes a puncturing algorithm for the turbo code in the uplink that satisfies all four puncturing conditions for the turbo codes listed above.

The core of the present invention is to modify the order of the interleaved bit strings in the coding / multiplexing block shown in FIG. 1, and to uniformly puncture by column in addition to the uniform puncturing by code symbol per row. Is that.

In the present invention, the interleaving order of channel coded bit strings is modified to fill each row of the interleaver memory in the following order. That is, they are stored in the interleaver's memory in the order of "x y z x z y x y z x z y ...".

The following describes the puncturing procedure for turbo code rate matching in the uplink according to the present invention in more detail. Although the number of columns K of the interleaver K is 1, 2, or 4, the present invention will be described only for the case where the number of columns K of the interleaver is 8, for convenience.

FIG. 4 is a diagram comparing an example of applying a puncturing algorithm for turbo code rate matching in an uplink with an example of applying a puncturing algorithm in units of existing code symbols.

4A illustrates an example in which an algorithm for puncturing parity bit components is alternately applied after determining a puncturing position of a code symbol so that puncturing occurs uniformly in units of code symbols among the puncturing algorithms for the turbo code.

As shown in FIG. 4A, conventionally, each row of the interleaver memory is filled in the order of "x y z x y z x y z ..." in the order of the interleaved bit strings in the coding / multiplexing block shown in FIG. The order of the interleaved bit strings can be easily implemented by switching at the output of the turbo coder used for channel coding.

Also, referring to FIG. 4A, among the turbo code puncturing conditions, the same puncturing condition for all frames that have undergone interleaving cannot be satisfied. In other words, the bit component is not punctured uniformly for each of the column bit streams that are the interleaved bit streams. In FIG. 4A, puncturing does not occur in the first, third, fifth, and seventh bitstreams.

However, in FIG. 4B to which the puncturing algorithm for the turbo code according to the present invention is applied, puncturing occurs in all of the column bit streams. This is because, unlike the conventional puncturing algorithm, the interleaver memory is filled with the order of the bit streams interleaved in the coding / multiplexing block shown in FIG. 1 in the order of "x y z x z y x y z x z y ...".

Here again, the order of the interleaved bit strings can be easily implemented by switching at the output of the turbo coder used for channel coding.

An example of applying a puncturing algorithm for a turbo code according to the present invention to obtain a code of 1/2 code rate at 1/3 code rate is FIG. 4B.

The following shows a puncturing algorithm for the turbo code in the uplink according to the present invention, Figure 5 is a diagram showing a puncturing position for the turbo code to realize uniform puncturing in units of code symbols according to the present invention. .

FIG. 6 is a diagram illustrating an actual puncturing pattern for puncturing turbo codes in code symbol units in the present invention.

In order to create a uniform puncturing pattern in units of code symbols shown in FIGS. 5 and 6, an initial error value for performing a rake matching procedure for each column of the interleaver And then use it to perform the puncturing algorithm.

First, the turbo code puncturing algorithm requires the following assumptions. Under this assumption, the puncturing distance q in code symbol units is calculated.

first, = Set of bits

second, ; Number of code symbols after puncturing

Third,

finally to be. here Means round off the decimal point.

"

"

In the above algorithm Is to prevent punctures in the same column over time, " Wow Represents the greatest common divisor of, Is not an integer but a multiple of 1/8.

Also " Is an expression representing a mapping rule according to the puncturing pattern for the turbo code of the present invention.

" Is an expression for calculating the shifting parameter S for each column of the interleaver.

Using the shifting parameter S calculated by the above algorithm, the following puncturing algorithm is performed for each column of the interleaver for the rate matching procedure.

First of all, the following puncturing algorithm requires the following assumptions.

first, = Set of bits

second, ; Number of code symbols after puncturing

Third,

Fourth, ; Column number of first interleaver; (here, Is the number of columns in the first interleaver)

"

; Initial error between the current puncturing ratio and the desired puncturing ratio

; The index of the current code symbol

; Error (e) update

; index Checking for puncturing on encoded symbols

; Error (e) update

; Index for next code symbol

; Initial error between the current puncturing ratio and the desired puncturing ratio

; The index of the current code symbol

; Error (e) update

; index For iteration over encoded symbols

; Error (e) update

; Index for next code symbol

"

The following describes an integrated puncturing algorithm for channelization codes according to the present invention. This integrated puncturing algorithm is a variant of the turbo code puncturing algorithm described above.

Before describing the integrated puncturing algorithm for the channelization code according to the present invention, the interleaver used to realize the present invention will be described.

In the present invention, a multi-stage interleaver (hereinafter referred to as MIL interleaver) is used.

The MIL interleaver writes the input bit string into the interleaver memory in units of rows and reads in units of columns to form an interleaved output bit string. The peculiarity of this is that the order of reading the interleaver's memory applies the bit reversing order rule.

For example, if the bit value indicating the column number where the interleaved bit string is output is 8 bits, the column bit string is not output in the order of column number "0 1 2 3 4 5 6 7" and the column number bit value is reversed. I.e., '0 (000) → 0 (000)', '1 (001) → 4 (100)', '2 (010) → 2 (010)', '3 (011) → 6 (110)' '4 (100) → 1 (001)', '5 (101) → 5 (101)', '6 (110) → 3 (011)', '7 (111) → 7 (111)' It outputs a serial bit string in the order of "0 4 2 6 1 5 3 7".

Table 1 below shows the order of the column bit strings output from the MIL interleaver for each interleaver column.

R (k) K R (0) R (1) R (2) R (3) R (4) R (5) R (6) R (7) 2 0 One 4 0 2 One 3 8 0 4 2 6 One 5 3 7

Table 1 shows the case where the columns of the interleaver are 2, 4, and 8, and R (k) shows the bit reversing result.

FIG. 7 illustrates an example of the order of the serial bit strings output from the MIL interleaver when K = 8 in Table 1 above.

In FIG. 7, the numbers of the shaded portions actually indicate the order in which the column bit strings are output from the interleaver. That is, the first column bit string is output first, the second column bit string is output fifth, the third column bit string is output third, the fourth column bit string is output seventh, and the fifth column is output. The bit string is output second, the sixth column bit string is output sixth, the seventh column bit string is output fourth, and the last eight column bit strings are output eighth.

FIG. 8 shows puncturing positions in code symbol units for channelization codes in order to realize uniform puncturing in code symbol units according to the present invention. FIG. 9 shows puncturing in code symbol units for channelization codes in the present invention. It shows the actual puncturing pattern being punched.

In FIG. 8, code symbols are grouped into even and odd code symbols, and uniform puncturing in units of code symbols is applied to each grouped code symbol. Then, puncturing occurs at the code bit positions of the shaded portions as shown in FIGS. 8A and 8B.

In this case, since all code symbols are grouped into even and odd code symbols, the puncturing algorithm uses 4 (= 8/2) as the number K of interleaved columns. In FIG. 8, the number of the uppermost shaded portion represents the column number on the interleaver memory being punctured.

Therefore, referring to FIG. 8, the puncturing pattern of the first column (0) of the interleaver for even-numbered code symbols is actually applied to the first column of the interleaver (which is the 30th code symbol) for the entire code bit in FIG. 9. The puncturing pattern of the second column 1 is actually applied to the second column of the interleaver (this is the 17th code symbol) for the entire code bit in FIG. 9.

Such a mapping rule can be generally expressed as Equation 1 and Equation 2 below.

Equation 1 shows a mapping rule for even-numbered code symbols, and equation 2 shows a mapping rule for odd-numbered code symbols.

In the above equations Is the number of columns in the interleaver. Except This can be

In order to make the puncturing pattern of FIG. 9 using the MIL interleaver as described above, an initial error value for each column of each interleaver Should be obtained. This initial error value In order to obtain, the shifting parameter S to be applied to the interleaver memory string for each bit string is calculated by the following first algorithm.

In the first algorithm for calculating the shifting parameter S, each interleaver memory string is first Consists of four code bits, each column Assume that puncturing occurs individually. At this point Is not actually a code symbol, but is considered a code symbol.

Before starting the first algorithm for calculating the shifting parameter S for the turbo code, the following basic premise is required.

First, code symbol ; here Is Maximum integer value not exceeding. Means rounding off.

Second, the number of code symbols after puncturing

Third, ; At this time Denotes an average puncturing distance in code symbol units.

From the basic premise mentioned above Is calculated, and Initial error value to apply to each column from the value The first algorithm to find is as follows.

"

"

In the first algorithm described above, "Is to prevent puncturing in the same row," " Wow Represents the greatest common divisor of.

Also " "," "," "I" Are the interleaving patterns of the MIL interleaver.

Last expression " "

Is an equation for calculating the shifting parameter S for each column of the interleaver.

An initial error value calculated from the shifting parameter S for each column by the first algorithm. Performs the following second algorithm for puncturing using.

First, the second algorithm requires the following assumptions.

first, = Set of bits

second, ; Number of code symbols after puncturing

Third,

Fourth, ; Column number of first interleaver; (here, Is the number of columns in the first interleaver)

Under this assumption, the second algorithm is as follows.

"

; Initial error

; The index of the current code symbol

; Error (e) update

; index Check if puncturing occurs for the encoded symbol

; Error (e) update

; Index for next code symbol

; Initial error

; The index of the current code symbol

; Error (e) update

; index For iteration over encoded symbols

; Error (e) update

; Index for next code symbol

"

The second algorithm is used when K is 2 or more. If K is 1, the puncturing algorithm in the existing downlink is applied. This is because if K is 1, MIL interleaving is practically unnecessary.

The following describes a third algorithm for calculating the shifting parameter S for the convolutional code. This third algorithm is a modification of the first algorithm for calculating the shifting parameters for the turbo code.

First, even in the convolutional code, even if punctured in each code symbol unit, there are code bits that do not affect the overall decoding performance. On the contrary, there is a code bit that excludes puncturing has a significant effect on the overall decoding performance.

As an example, considering a convolutional code of 1/3 code rate, assuming that puncturing only the first bit component (x) improves the overall decoding performance, the convolutional code for the uplink to be implemented at this time The puncturing algorithm makes it possible to puncture only the x bit component among the bit components x, y, and z.

To this end, in the present invention, when interleaving by changing the order of convolutionally coded bit strings, each row is filled in the following order. That is, "y x z y x z y x z y ..." is stored in the interleaver memory in this order.

Afterwards, an initial error value for uniform puncturing in units of code symbols on the interleaver memory And calculate the calculated initial error Is applied to the columns of each interleaver to perform puncturing.

Examples of puncturing a total of 16 code bits by applying a puncturing algorithm in the uplink that punctures only the bit component x to 288 code bits, that is, 96 (= 288/3) code symbols are illustrated in FIGS. 10 and 11. Shown in

FIG. 10 is a view illustrating a pattern in code symbol units for puncturing only a specific bit component (x) in a convolutional code to realize uniform puncturing in code symbol units according to the present invention.

FIG. 11 is a diagram illustrating an actual puncturing pattern for puncturing only a specific bit component (x) in code symbol units in a convolutional code.

In order to make a uniform puncturing pattern in units of code symbols shown in FIGS. 10 and 11, an initial error value for each column of each interleaver Should be obtained. This initial error value In order to calculate, the shifting parameter S to be applied to the interleaver memory string for each bit string is calculated by the following third algorithm.

Before starting the third algorithm for calculating the shifting parameter S for the convolutional code, the following basic premise is required.

First, code symbol ; here Is Maximum integer value not exceeding. Means rounding off.

Second, the number of code symbols after puncturing

Third, ; At this time Denotes an average puncturing distance in code symbol units.

This basic premise is the same as the basic premise in the first algorithm for calculating the shifting parameter S for the turbo code. From the basic premise mentioned above Is calculated, and Initial error value to apply to each column from the value The third algorithm to find is as follows.

"

In the third algorithm described above, "Is to prevent puncturing in the same row," " Wow Represents the greatest common divisor of, " "I" Are the interleaving patterns of the MIL interleaver.

Also " Is an expression for calculating the shifting parameter S for each column of the interleaver.

An initial error value calculated from the shifting parameter S for each column by the third algorithm. To perform the second algorithm for puncturing already described.

As another example, if puncturing only the second bit component (y) of each code symbol in the convolutional code improves the overall decoding performance, then interleaving the convolutionally coded bitstreams fills each row in the following order: do. That is, "x y z x y z x y z x y z ..." is stored in the interleaver memory in this order.

Thereafter, puncturing is performed by applying the same to the third algorithm and the second algorithm.

On the other hand, when puncturing the bit components of each code symbol in the convolutional code, it is necessary to puncture the first bit component (x) first and then repeat the second bit component (y) in the order of puncturing. In order to improve performance, when interleaving convolutionally coded bit streams, they are stored in the memory of the interleaver in the order of “xyzxzyxyzxzy…” and then punctured by applying them to the first algorithm and the second algorithm.

As a result, the second algorithm is an integrated algorithm that can be applied to puncturing for the turbo code and the convolutional code, which are channelization codes in the uplink.

As described above, the integrated puncturing algorithm for the channelization code in the uplink is summarized below.

Prior to starting the puncturing algorithm, which code is used as the channelization code in the turbo code or the convolutional code? Is the number of columns (K) of the interleavers used simultaneously? According to the channel coding after the output pattern is determined.

The bit strings output after the channel coding are filled in the interleaver memory, and then the interleaved bit strings are applied to the following integrated puncturing algorithm.

"if (number of columns in the interleaver K = 1)

{Apply puncturing algorithm on existing downlink}

else {

if (convolution code)

Using either the first algorithm or the third algorithm for each column

Calculate Shifting Parameter (S)

else if (turbo code)

Calculate shifting parameter S for each column using the first algorithm

Perform a Second Punching Algorithm for Channelization Code in Uplink}

As described above, in the rate matching method for the channelization code in the uplink according to the present invention, a uniform code symbol distance for each parity bit component of RSC coders among puncturing conditions for the turbo code in the uplink Punching with is realized.

In addition, integrated puncturing algorithms for channelization codes such as turbo codes and convolutional codes can be implemented to achieve optimal rate matching in the uplink.

In addition, puncturing for convolutional codes in the uplink can be realized, and puncturing in code symbol units is performed unlike the conventional puncturing algorithm for convolutional codes. In addition, in the integrated puncturing algorithm according to the present invention, since puncturing occurs for each code symbol, it is possible to realize uniform puncturing to significantly improve overall decoding performance.

Claims (8)

In the uplink of the mobile communication system using the channelization code, Outputting a plurality of bit strings in code symbol units by performing channel coding on a transmission channel; Grouping and interleaving the bit strings in code symbol units so that uniform puncturing occurs in units of code symbols at regular intervals with respect to the outputted plurality of bit strings; Performing puncturing on the interleaved bit streams in units of code symbols at predetermined intervals. The method of claim 1, wherein the puncturing step, Except for the specific bit string output by the channel coding, the rate matching method characterized in that the remaining bit strings used for decoding are performed in units of code symbols at regular intervals. 3. The method of claim 2, wherein the puncturing excludes puncturing for the specific bit string having a relatively high importance in consideration of the importance of each bit string output by the channel coding. The method of claim 1, wherein the puncturing step includes applying a uniform puncturing algorithm at a predetermined interval in each column to the interleaved bit streams. In the uplink of the mobile communication system using the channelization code, Outputting the systematic bit component and one or more parity bit components in symbol units in parallel as a result of channel coding on the transmission channel; Interleaving the parity bit components with different priorities for each symbol unit output; And performing puncturing on the interleaved parity bit components at a predetermined interval of each symbol unit. The method of claim 5, wherein the puncturing step, And a uniform number of puncturing occurs for each column bit stream after the interleaving. Outputting the systematic bit component and one or more parity bit components in symbol units as a result of channel coding on a transmission channel of a mobile communication system; Parity bit components are grouped into different priorities and interleaved for each output symbol unit; Performing puncturing on the parity bit components of each interleaving group at predetermined intervals in each symbol unit. The method of claim 7, wherein the puncturing step, And a uniform number of puncturings occur at regular intervals for each column bit string of each interleaving group.