KR101116264B1 - Apparatus and method for interleaving in communication system - Google Patents

Abstract

The present invention relates to an interleaving apparatus and method in a communication system. The interleaving method according to the present invention comprises the steps of determining a data recording start row of an R1 × C1 interleaving matrix using a unique identifier of a terminal, writing input data into the interleaving matrix from the starting row, and interleaving matrix Reading the data recorded in step Sequentially. As described above, the present invention can perform terminal-specific interleaving using the terminal identifier (IMSI), thereby protecting data between the base station and the terminal in an effective and simple manner.

Interleaving, Deinterleaving, IMSI, Encryption

Description

Interleaving apparatus and method in communication system {APPARATUS AND METHOD FOR INTERLEAVING IN COMMUNICATION SYSTEM}

1 is a diagram illustrating an interleaving scheme according to the prior art.

2 is a block diagram of an interleaver in a communication system according to an embodiment of the present invention;

3 is a diagram illustrating a procedure for interleaving data in an interleaver according to an embodiment of the present invention.

4 is a diagram illustrating a configuration of a deinterleaver in a communication system according to an embodiment of the present invention.

5 is a diagram illustrating a procedure for deinterleaving data in a deinterleaver according to an embodiment of the present invention.

6 is a diagram illustrating an interleaving scheme according to the present invention.

7 illustrates a deinterleaving scheme according to the present invention.

The present invention relates to an interleaving / deinterleaving apparatus and method in a communication system, and more particularly, to an apparatus and method for performing terminal-specific interleaving.

Today's mobile communication systems are evolving into high-speed, high-quality wireless data packet communication systems to provide data services and multimedia services beyond voice-oriented services. High Speed Down-link Packet Access (HSDPA) and 1xEVDV (Evolution Data and Voice) standardization based on 3rd Generation Partnership Project (3GPP) and 3GPP2 are high speed, high quality wireless data packets of 2Mbps or more in 3rd generation mobile communication systems. It is part of the effort to find a solution for the transmission service. On the other hand, the fourth generation mobile communication system aims to provide higher speed and higher quality multimedia services.

In such a mobile communication system, a factor that hinders high-speed and high-quality data service is largely due to a channel environment. For example, in addition to white noise, the channel environment is frequently changed due to fading, shadowing, Doppler effect due to the movement of the terminal and frequent speed changes, and interference by other users and multipath signals. Accordingly, in order to provide a high speed wireless data packet service, other advanced technologies that can increase adaptability to channel changes are needed in addition to the general technologies provided in existing 2nd or 3rd generation mobile communication systems. The high-speed power control scheme adopted in the conventional mobile communication system improves the adaptability to channel changes, but adapts to 3GPP (3rd Generation Partnership Project), 3GPP2, and IEEE 802.16, which are in the process of standardizing high-speed data packet transmission systems. Adaptive Modulation & Coding Scheme (hereinafter referred to as AMCS) and Hybrid Automatic Repeat Request (hereinafter referred to as H-ARQ) techniques are commonly mentioned.

In addition, the mobile communication system uses interleaving for reliable transmission of data. The interleaving is a technique for controlling the damage of bits in a fading environment to be distributed to various places instead of being concentrated in one place. In general, a transmitter transmits data by interleaving to prevent aggregation errors, and a receiver performs deinterleaving to arrange interleaved data in an original order.

Hereinafter, a block interleaving scheme proposed in 3GPP will be described. The existing interleaving ice meal proceeds in the following order.

1) The number C1 of columns of the interleaving matrix is obtained according to a transmission time interval (TTI).

2) Find the number R1 of the rows of the interleaving matrix.

3) Write the input stream sequentially in row units.

4) Heat and heat are exchanged according to the permutation rules as shown in Table 1 below.

5) Read data sequentially in column units.

TTI Number of columns C1 Inter-column permutation patterns 10 ms One <0> 20 ms 2 <1, 1> 40 ms 4 <0, 2, 1, 3> 80 ms 8 <0, 4, 2, 6, 1, 5, 3, 7>

For example, if the TTI is 20 ms and the input stream is x0, x1, x2, x3, ..., xi-1, xi, the input stream is recorded in the interleaving matrix as shown in FIG. x0, x2, x4, ..., xi-1, x1, x3, x5, xi.

Since the conventional interleaving method uses the same interleaving method for all terminals, there is a problem that data of other users can be recovered only by knowing the interleaving rules. That is, a method for protecting data between a base station and a user equipment (UE) is needed. If the terminal uses its own interleaving method instead of the same interleaving method, it may not only protect data between the base station and the terminal more powerfully but also improve interleaving performance.

Accordingly, an object of the present invention is to provide an apparatus and method for improving interleaving / deinterleaving performance in a communication system.

Another object of the present invention is to provide an apparatus and method for performing terminal-specific interleaving / deinterleaving in a communication system.

Another object of the present invention is to provide an apparatus and method for performing interleaving / deinterleaving using a terminal identifier in a communication system.

An interleaving apparatus according to the present invention for achieving the above objects comprises: a start determination section for determining a data write start row of an R1 × C1 interleaving matrix using a unique identifier of a terminal; And a write address generator for generating a write address for recording, and an output address generator for generating an output address for outputting data recorded in the interleaving matrix in column units.

The deinterleaving apparatus according to the present invention comprises a start determination unit for determining a data read start row of an R1 × C1 deinterleaving matrix using a unique identifier of a terminal, and a record for recording input data in the deinterleaving matrix in units of columns. And a read address generator for generating an address and a read address generator for generating a read address for reading data written in the deinterleaving matrix from the start row.

The interleaving method according to the present invention comprises the steps of determining a data recording start row of an R1 × C1 interleaving matrix using a unique identifier of a terminal, writing input data into the interleaving matrix from the starting row, and interleaving matrix And sequentially reading the data recorded in the column unit.

The deinterleaving method according to the present invention comprises the steps of determining a data read start row of an R1 × C1 deinterleaving matrix using a unique identifier of a terminal, writing input data in the deinterleaving matrix in columns; And reading out the data recorded in the deinterleaving matrix from the starting row.

Hereinafter, the operating principle of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the present invention, detailed descriptions of well-known functions or configurations will be omitted if it is determined that the detailed description of the present invention may unnecessarily obscure the subject matter of the present invention. The following terms are defined in consideration of the functions of the present invention, and may be changed according to the intentions or customs of the user, the operator, and the like. Therefore, the definition should be based on the contents throughout this specification.

Hereinafter, a method for performing terminal-specific interleaving / deinterleaving in a communication system will be described. Hereinafter, a first interleaving scheme proposed in 3GPP will be described as an example. However, the interleaving ice type according to the present invention can be equally applied to interleavers in various fields such as channel interleavers of other communication systems (eg, orthogonal frequency division multiplexing (OFDM) -based communication systems), internal interleavers of turbo coders, and the like.

2 is a block diagram of an interleaver in a communication system according to an embodiment of the present invention.

As shown, the interleaver includes a start determiner 201, a write address generator 203, a read address generator 205, and an interleaver memory 207.

Referring to FIG. 2, the start determination unit 201 first determines the number of columns C1 and the number of rows R1 of an interleaving matrix according to a given transmission time interval (TTI) size. Here, the number of columns C1 is determined as shown in Table 1, and the number of rows R1 is determined as shown in Equation 1 below.

Where Xi is the number of bits in the input stream.

In addition, the start determination unit 201 determines and outputs a _start row (R _start ) of interleaving using a unique identifier (eg, International Mobile Subscriber Identity (IMSI)) of the terminal. The start row R _start of the interleaving is determined as in Equation 2 below.

As such, when the parameters necessary for interleaving are determined, the start determination unit 201 provides the determined interleaving parameters R1, C1, and R _start to the recording address generator 203 and the read address generator 205. do.

The write address generator 203 generates and outputs a write address for writing input data into the interleaver memory 207. In the interleaving method according to an embodiment of the present invention, a rule for generating a write address is as follows, and the write address generator 203 generates and outputs a write address according to the following rule.

Ⅰ) to the R _start to the start line and records the input stream with the line-by-line sequentially while incrementing the R _count.

R _real = (R _start + R _count )% R1

Where 0 <= R _count <R1 and R _real is the value of the row where the input stream is recorded.

Ii) Perform heat exchange according to the permutation rules given in Table 1.

That is, the write address generation unit 207 generates and outputs a write address in consideration of the heat exchange. The interleaver memory 207 then randomly writes the input stream in accordance with the write address from the write address generator 203.

When all the input streams are recorded in the interleaver memory 207, the read address generator 203 generates and outputs a read address for sequentially reading data written in the interleaver memory 207 in units of columns. Then, the interleaver memory 207 reads the stored data according to the read address from the read address generator 205.

Although the above-described embodiment of the present invention defines up to heat exchange in the recording mode, in another embodiment, the row-by-row recording may be defined as the recording mode, and the remaining column-unit exchange and column unit read may be defined as the read mode.

As described above, the present invention uses IMSI as a factor for determining the _start row R _start of interleaving. The base station acquires the IMSI of the terminal through a radio resource control (RRC) connection procedure. In brief, the terminal transmits an RRC connection request message to the base station through a PRACH (Physical Random Access Channel). The message includes information for identifying a terminal, and among them, an International Mobile Subscriber Identity (IMSI) is a subscriber identity of each terminal and has a different value for each terminal. The present invention uses the IMSI value to have a unique interleaving start row for each terminal.

3 illustrates a procedure for interleaving data in an interleaver according to an embodiment of the present invention.

Referring to FIG. 3, the interleaver first determines the number C1 of columns of the interleaving matrix according to the TTI size given in step 301. Here, the number C1 of the columns may be obtained through a predetermined table (Table 1). In step 305, the interleaver determines the number of rows R1 using the number C1 of the columns. The number R1 of the rows is determined as in Equation 1 above.

As such, when the number of columns C1 and the number of rows R1 of the interleaving matrix is determined, the interleaver proceeds to step 305 to determine the starting row R _start of the interleaving matrix as shown in Equation 2 above. In this case, the value of the variable R _real is determined as the determined start row value (R _start ). In addition, the variable R _count value representing the value (or number) of the row where data is actually written is initialized to '0'.

In step 307, the interleaver checks whether the variable R _count value is equal to "R1-1". In other words, it is checked whether the operation of writing data to the interleaving matrix is completed. If the variable R _count value is different from "R1-1", the interleaver proceeds to step 309 and sequentially records the input stream in the row indicated by the variable R _count value. In step 311, the interleaver increases the value of the variable R _count by '1', updates the variable R _count value as shown in Equation 3 below in step 313, and returns to step 307 to repeat the following steps. Do it.

On the other hand, if it is determined in step 307 that the variable R _count value is equal to "R1-1", the interleaver proceeds to step 315 to perform heat exchange according to the permutation rules shown in Table 1 above. In step 317, the interleaver reads the permutated data in units of columns through heat exchange to complete interleaving.

4 illustrates a configuration of a deinterleaver in a communication system according to an embodiment of the present invention.

As shown, the deinterleaver includes a start determination unit 401, a read address generator 403, a write address generator 405, and a deinterleaver memory 407.

Referring to FIG. 4, first, the start decision unit 401 determines the number of columns C1 and the number of rows R1 of the deinterleaving matrix according to a given TTI size. Here, the number of columns C1 is determined as shown in Table 1, and the number of rows R1 is determined as shown in Equation 1 above.

In addition, the start determination unit 401 determines a start row R _start of deinterleaving using a unique identifier (eg, an International Mobile Subscriber Identity (IMSI)) of the terminal. The start row R _start of the deinterleaving may be determined as in Equation 2. As such, when the parameters necessary for deinterleaving are determined, the start determination unit 401 reads the determined deinterleaving parameters R1, C1, and R _start from the read address generator 403 and the write address generator 405. To provide.

Then, the write address generator 405 generates and outputs a write address (Write ADDR) for sequentially recording the input stream in units of columns. The deinterleaver memory 407 sequentially stores the input stream in accordance with the write address from the write address generator 405.

When all of the input streams are written to the deinterleaver memory 407, the read address generator 403 generates and outputs a read address (Read ADDR) for reading data recorded in the deinterleaver memory 407. do. A rule for generating a read address in the deinterleaving method according to an embodiment of the present invention is as follows, and the read address generator 403 generates and outputs a read address according to the following rule.

열) Exchange heat and heat in the reverse order of permutation rules as shown in Table 1.

Ii) R _start is read as the starting row and data is read sequentially in row units while increasing R _count .

R _real = (R _start + R _count )% R1

Here, 0 <= R _count <R1 and R _real is a value of a row from which data is read.

Then, the deinterleaver memory 407 reads the stored data according to the read address from the read address generator 403.

In the above-described embodiment of the present invention, up to heat exchange is defined as a read mode, but in another embodiment, column-based recording and heat exchange may be defined as a recording mode, and the remaining row unit read may be defined as a read mode.

5 illustrates a procedure for deinterleaving data in a deinterleaver according to an embodiment of the present invention.

Referring to FIG. 5, the deinterleaver first determines the number C1 of columns of the deinterleaving matrix according to the TTI size given in step 501. Here, the number C1 of the columns is obtained through a predetermined table (Table 1). In operation 503, the deinterleaver determines the number of rows R1 using the number of columns c1. The number R1 of the rows is determined as in Equation 1 above.

As described above, when the number of columns C1 and the number of rows R1 of the deinterleaving matrix are determined, the deinterleaver proceeds to step 505 to determine the start row R _start of the deinterleaving matrix as shown in Equation 2 above. The variable R _real value is determined as the determined start row value R _start . In addition, the variable R _count value representing the value (or number) of the row where data is actually read is initialized to '0'.

In operation 507, the deinterleaver sequentially records the input stream in a deinterleaving matrix (memory) in units of columns. In operation 509, the deinterleaver performs heat exchange in the reverse order of the permutation rule as shown in Table 1 above.

After performing the heat exchange in this way, the deinterleaver checks whether the variable R _count value is equal to "R1-1" in step 511. In other words, it is checked whether the operation of reading data from the deinterleaving matrix is completed. If the variable R _count value is different from "R1-1", the deinterleaver proceeds to step 513 to sequentially read data from the row indicated by the variable R _count value. In step 515, the deinterleaver increases the variable R _count value by '1', updates the variable R _count value as shown in Equation 3 in step 517, and returns to step 511 to perform the following steps again. .

On the other hand, if it is determined in step 511 that the variable R _count value is equal to "R1-1", the deinterleaver determines that all data has been read and completes the deinterleaving operation.

6 is a view for explaining an interleaving scheme according to the present invention.

As shown, the input streams are sequentially recorded in row units in an interleaving matrix (memory) of size R1 × C1. At this time, the row R _{start at} which data recording is started is determined according to an identifier unique to the terminal (eg, IMSI). When data recording from the start row R _start to the last row is completed, the remaining data is recorded sequentially from the first row.

In this manner, when data recording is completed, heat exchange is performed according to a predetermined permutation rule (Table 1). For example, when the TTI size is 40 ms, the number of columns c1 is four, and inter-column permutation is performed to exchange the second and third columns.

In this manner, after data recording is completed, interleaving is completed by sequentially reading the data recorded in the interleaving matrix in column units.

7 is a view for explaining a deinterleaving method according to the present invention.

As shown, the input streams are sequentially recorded in units of columns in a deinterleaving matrix (memory) of size R1 × C1.

In this manner, when data recording is completed, heat exchange is performed in the reverse order of the predetermined permutation rule (Table 1). For example, if the TTI size is 40 ms, the number of columns c1 is four, and inter-column permutation is performed to exchange the second and third columns.

Thereafter, the data recorded in the deinterleaving matrix is sequentially read in units of rows. In this case, the row R _{start at} which data reading is started is determined according to a terminal unique identifier (eg, IMSI). When data reading from the start row R _start to the last row is completed, the remaining data is read sequentially from the first row.

Meanwhile, in the detailed description of the present invention, specific embodiments have been described, but various modifications are possible without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be determined not only by the scope of the following claims, but also by those equivalent to the scope of the claims.

As described above, the present invention has an advantage of effectively and simply protecting data between the base station and the terminal by performing terminal-specific interleaving using the terminal identifier (IMSI). In addition, since the input stream is distributed more randomly than the conventional method, it is possible to exhibit good performance against aggregation errors due to fading. In addition, since the unique key value of the terminal is used without using complicated hardware such as ciphering, hardware can be easily implemented.

Claims (22)

In an interleaving apparatus, A start determination unit for determining a data recording start row of the R1 × C1 interleaving matrix using a unique identifier of the terminal; A write address generator for generating a write address for writing input data into the interleaving matrix from the start row; And an output address generator for generating an output address for outputting data recorded in the interleaving matrix in column units. The method of claim 1, Wherein the unique identifier is an International Mobile Subscriber Identity (IMSI). 3. The method of claim 2, The start determining unit is characterized in that for determining the _start row (R _start ) as shown in the following equation.

The method of claim 1, The write address generation unit may write the input data to the interleaving matrix in a cyclic manner from the start row, and generate a write address for exchanging the recorded data according to a predetermined permutation rule. Device. The method of claim 1, And an interleaver memory for storing the input data according to the write address and outputting the stored data according to the output address. The method of claim 1, Wherein the number of columns (C1) and the number of rows (R1) of the interleaving matrix are determined according to a given transmission time interval (TTI) size. In the deinterleaving apparatus, A start determination unit for determining a data read start row of the R1 × C1 deinterleaving matrix by using a unique identifier of the terminal; A write address generation unit for generating a write address for recording input data in the deinterleaving matrix in column units; And a read address generator for generating a read address for reading data written in the deinterleaving matrix from the start row. The method of claim 7, wherein Wherein the unique identifier is an International Mobile Subscriber identity (IMSI). The method of claim 8, The start determining unit is characterized in that for determining the _start row (R _start ) as shown in the following equation. The method of claim 7, wherein The read address generator may heat exchange data recorded in the deinterleaving matrix according to a predetermined permutation scheme, and generate a read address for reading the heat exchanged data in a cyclic manner from the start row. Characterized in that the device. The method of claim 7, wherein And a deinterleaver memory for storing the input data according to the write address and outputting the stored data according to the output address. The method of claim 7, wherein And the number of columns (C1) and the number of rows (R1) of the deinterleaving matrix are determined according to a given transmission time interval (TTI) size. In the interleaving method, Determining a data recording start row of an R1 × C1 interleaving matrix using a unique identifier of the terminal; Writing input data into the interleaving matrix from the starting row; And sequentially reading data recorded in the interleaving matrix in column units. The method of claim 13, Wherein the unique identifier is an International Mobile Subscriber Identity (IMSI). The method of claim 14, The start row (R _start ) is characterized in that determined by the following formula.

The method of claim 13, wherein the recording process comprises: Recording the input data in the interleaving matrix from the starting row in a cyclic manner; Heat exchanging said recorded data according to a predetermined permutation rule. The method of claim 13, And the number of columns C1 and the number of rows R1 of said interleaving matrix are determined according to a given TTI size. In the deinterleaving method, Determining a data read start row of an R1 × C1 deinterleaving matrix by using a unique identifier of the terminal; Recording input data in columns in the deinterleaving matrix; And reading out the data recorded in the deinterleaving matrix from the starting row. The method of claim 18, And wherein said unique identifier is an international mobile subscriber identity (IMSI). The method of claim 19, The start row (R _start ) is characterized in that determined by the following formula.

The method of claim 18, wherein the reading process, Heat exchanging the data recorded in the deinterleaving matrix according to a predetermined permutation scheme; And reading the heat exchanged data in a cyclic manner from the starting row. The method of claim 18, And the number of columns (C1) and the number of rows (R1) of the deinterleaving matrix are determined according to a given transmission time interval (TTI) size.

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