KR101093946B1 - Apparatus and method of soft metric mapping inputted to channel decoder in hierarchical modulation system - Google Patents

Abstract

The present invention relates to demodulation of a data communication system using a multilevel modulation scheme, and more particularly, to an apparatus and a method for calculating an input softness value of a channel decoder in a demodulator of a data communication system. The apparatus of the present invention receives a received signal consisting of a quadrature component and an in-phase component, and determines soft values for decoding the received signal. In particular, in case of using a nonuniform constellation in which the distance between signal points is not uniform in 16QAM and 64QAM, the minimum distance 2a between the signal points and the distance between each axis and the signal point closest to the origin in the constellation Using the multiple S for a, the soft values associated with the demodulation symbols are determined. This invention can design an efficient and low complexity soft-phase inversion machine. In addition, it is possible to implement all three modulation schemes and the hierarchical mode in each modulation scheme by adding only a few operations without requiring separate circuits separately for various conditions.

Channel Decoder, Soft metric value, Hierarchical Modulation, 16QAM, 64QAM

Description

Apparatus and method for calculating a soft value input to a channel decoder in a communication system using a hierarchical modulation scheme {APPARATUS AND METHOD OF SOFT METRIC MAPPING INPUTTED TO CHANNEL DECODER IN HIERARCHICAL MODULATION SYSTEM}

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a diagram showing a signal constellation of 16QAM modulation.

FIG. 2 is a flow chart of calculating the ductility values of 16QAM using uniform constellations in accordance with one embodiment of the present invention. FIG.

Figure 3 is a block diagram for obtaining a soft value of the hierarchical modulation method according to an embodiment of the present invention.

FIG. 4 is a block diagram of obtaining softness values of 16QAM using a uniform constellation according to an embodiment of the present invention. FIG.

5 is an example of the uniform constellation of 16QAM.

6 and 7 are examples of non-uniform constellations of 16QAM.

8 is an example of the uniform constellation of 64QAM.

9 and 10 are examples of non-uniform constellations of 64QAM.

11 is a flow chart for finding soft values of 16QAM in accordance with a preferred embodiment of the present invention.

12A and 12B are flow charts for finding soft values of 64QAM in accordance with a preferred embodiment of the present invention.

FIG. 13 is a block diagram showing soft values of 16QAM according to a preferred embodiment of the present invention. FIG.

FIG. 14 is a block diagram showing soft values of 64QAM according to a preferred embodiment of the present invention. FIG.

FIG. 15 is an integrated block diagram of calculating soft values of QPSK, 16QAM, and 64QAM in accordance with a preferred embodiment of the present invention. FIG.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to demodulation of a data communication system employing a multi-level modulation scheme, and more particularly, to an apparatus for calculating an input value of a channel decoder in a demodulator of a data communication system. And to a method.

As full-scale digital broadcasting begins, various broadcasting services have appeared for each medium. Among other things, the implementation of mobile TV reception technology will enable viewers to watch broadcasts anytime and anywhere. Up to now, broadcasters have been able to provide one broadcast service on one channel, but when using digital broadcasting's hierarchical modulation (HM) method, which uses a multicarrier method, two different channels are used in one channel. A broadcast service can be provided at the same time. If a broadcaster broadcasts a Moving Picture Experts Group (MPEG) transport stream (TS) in a different modulation scheme in one channel, the viewer can watch the broadcast on a desired channel. Such a hierarchical modulation technique is one of additional broadcast services not considered in the analog era.

Hierarchical modulation service was originally used for satellite broadcasting. Since satellite radio waves use the microwave frequency band, when there is a lot of rainfall due to the nature of the radio wave signal, the video signal is not only temporarily stopped due to the rainfall, but also in the case of an audio signal, it is silent. .

Therefore, in order to reduce the interference due to the multipath caused by heavy rain, the modulation method used in the high hierarchical (HH) is modulated and transmitted to the low hierarchical (LH) to maximize information transmission. Let's do it. However, data modulated to the LH layer is strong in rainfall but has a disadvantage in that the amount of information that can be transmitted is reduced.

The video automatically switches between these layers as the receiver evaluates the reception quality, and the voice can be sent to the lower layers because of the small amount of original data. However, this low layer transmission cannot deliver all of the important broadcast programs made up of a lot of data.

Unlike the hierarchical modulation service to improve the quality of satellite reception, DVB-T (Digital Video Broadcasting-Terrestrial), which is adopted as the European terrestrial digital broadcasting method, is coded orthogonal frequency division multiplex (OFDM). Due to the use of the technology, it is designed to enable mobile and mobile reception services as well as fixed reception using outdoor antennas. In addition, hierarchical modulation (HM) used for COFDM means that two separate data streams, a high priority (HP) stream, are implemented in a low priority (LP) stream to be modulated into one DVB-T transport stream. Depending on the receiver, both streams may be received or only HP streams may be received. The HP stream and the LP stream may be the same content or may be completely different content. In other words, a broadcaster can provide two completely different services with two different types in one channel. In general, LP streams have a high bit rate. DVB-T uses three modulation schemes: Quadrature Phase Shift Keying (QPSK), 16-ary Quadrature Amplitude Modulation (16QAM), and 64QAM (64QAM). A hierarchical modulation structure can be applied. Therefore, in a communication system using a hierarchical modulation structure such as DVB-T, a soft metric mapping rule for using the hierarchical modulation method is required.

Therefore, the present invention devised to solve the problems of the prior art operating as described above, the input soft value (soft decision) of the channel decoder calculated by the double minimum trick method in the demodulator of the communication system using the hierarchical modulation method An apparatus and method are provided for a simple calculation of a value without a mapping table or complicated processing required to obtain a minimum distance value from a received signal.

An embodiment of the present invention, which is designed to achieve the above object, receives a k-th received signal R _k composed of quadrature component Y _k and in-phase component X _k , and receives the received signal R _k (X _k In the 16QAM demodulation device for determining the coupling values for the decoding of, Y _k ),

Of the four demodulation symbols, using the minimum distance (2a) between the signal points in the 16QAM constellation, the signal point closest to the origin in the 16QAM constellation, the distance (α) between each axis, and the quadrature component Y _k . A first ductility value determination unit for determining ductility values Λ (S _k , ₂ ) and Λ (S _k , ₀ ) of two demodulation symbols related to the quadrature component Y _k ;

By using the minimum distance 2a, the distance α, and the in-phase component X _k , the coupling values Λ (S _k) of two demodulation symbols related to the in-phase component X _k among the four demodulation symbols , ₃ ), and a second ductility value determining unit for determining Λ (S _k , ₁ )).

Another embodiment of the invention, k-th receive consisting of quadrature phase component Y _k and a in-phase component X _k signal R _k (X _k, Y _k) of the received signal R receives input _k (X _k, Y _k A 64QAM demodulation device for determining soft values for decoding of

Of the six demodulation symbols, using the minimum distance (2a) between the signal points in the 64QAM constellation, the signal point closest to the origin in the 64QAM constellation, the distance (α) between each axis, and the quadrature component Y _k . A first ductility value determination unit for determining ductility values Λ (S _k , ₄ ), Λ (S _k , ₂ ), Λ (S _k , ₀ ) of the three demodulation symbols related to the quadrature component Y _k ; ,

By using the minimum distance 2a and the distance α and the in-phase component X _k , the coupling values Λ (S _k of three demodulation symbols related to the in-phase component X _k among the six demodulation symbols , ₅ ), Λ (S _k , ₃ ), and Λ (S _k , ₁ )).

The operation principle of the preferred embodiment 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.

The main subject of the present invention to be described later is a soft metric value that is input to a channel decoder in a demodulator of a data communication system adopting a multilevel modulation scheme such as 16QAM and 64QAM. It is decided by.

A transmitter of a data communication system modulates and transmits symbols encoded by a channel encoder using 6QAM or 64QAM, which is one of a multilevel modulation scheme used to increase spectral efficiency. In order to perform soft decision decoding in the channel decoder of the receiver, the demodulator is composed of two in-phase (I) signal components and a quadrature phase (Q) signal component. A mapping algorithm for generating soft decision values corresponding to each of the output bits of the channel encoder is performed.

There are two main ways in this thought algorithm. Nokia's proposed simple metric procedure and Motorola's proposed dual minimum metric procedure, both of which provide log likelihood ratios for each output bit. Calculate and use it as the input coupling value of the channel decoder.

The simple matrix method is a mapping algorithm that transforms a complex LLR equation into a simple approximation equation. The LLR calculation is simple, but the degradation of performance due to LLR distortion caused by using the approximation equation is pointed out as a disadvantage. On the other hand, the double minimum metric method is a mapping algorithm that uses the LLR calculated using a more accurate approximation as the input of the channel decoder, and has the advantage of significantly improving the performance deterioration caused by using the simple matrix method. It requires more computational complexity and has a problem that a significant increase in complexity is expected in hardware implementation. In this regard, the algorithm proposed by Samsung can obtain the channel decoder input coupling value calculated by the double minimum metric method without a mapping table or complicated calculation required to obtain the minimum distance value from the received signal. That's how it is.

<< uniform signal constellation >>

A detailed algorithm for determining multidimensional coupling values from a 2D received signal is as follows. The output sequence of the binary channel encoder is divided into m symbols and then mapped to a specific signal point among M (= 2 ^m ) signal points. The mapping follows the Gray coding rule. When the above formula is formulated, Equation 1 is obtained.

In Equation 1, s _{k, i} (i = 0, 1, ..., m-1) denotes an i th symbol of an output sequence of a binary channel encoder mapped to a k th signal point, and I _k and Q _k denotes an in-phase signal component and a quadrature signal component of the k-th signal point, respectively. In the case of 16QAM, m = 4, and FIG. 1 shows a signal constellation corresponding to 16QAM. As shown, the constellation diagram consists of 16 signal points, each quadrant of 4 signal points. Each signal point is represented by four symbols. Four demodulation symbols corresponding to the illustrated signal points represent Q, Q, I, I signal components in order. For example, when FIG. 1 divides the first quadrant into four regions, the symbol string "0000" is mapped to the upper right region in the first quadrant divided into the four regions, and "0100" is represented in the lower right region. "0001" maps to the upper left region, and "0101" maps to the lower left region. Here, the distances between adjacent signal points are all equal to 2a.

A symbol demodulator output of a receiver corresponding to I _k and Q _k is represented in the form of a complex number as shown in Equation 2 below.

,

는 평균이 0이고 분산이

인 I 채널과 Q 채널에 대한 가우시안 잡 음(Gaussian noise)으로 통계적으로 서로 독립인 관계이다. s_k,i = (i=0, 1, …, m-1)와 관련된 LLR(log likelihood ratio)은 다음 <수학식 3>에 의해 구할 수 있으며, 이를 채널복호기(channel decoder)에 입력되는 연성값으로 사용할 수 있다.In Equation 2, X _k and Y _k denote in-phase signal components and quadrature signal components of the symbol demodulator output, respectively, and g _k denotes gains of a transmitter, a transmission medium, and a receiver. Is a complex coefficient,

,

Is 0 and the variance is

Gaussian noise for the I and Q channels is statistically independent of each other. The log likelihood ratio (LLR) related to s _{k, i} = (i = 0, 1, ..., m-1) can be obtained by the following Equation 3, which is input to the channel decoder. Can be used as a value.

In Equation 3, K is an arbitrary constant, and Pr {A | B} is a conditional probability defined as an occurrence probability of event A when event B occurs. However, since Equation 3 is non-linear and involves a relatively large amount of computation, an algorithm capable of approximating Equation 3 is required for actual implementation. In the case of a Gaussian noise channel with g _k = 1 in Equation 2, Equation 3 is approximated by the double minimum matrix method as shown in Equation 4 below.

이며, z_k(s_k,i =0)와 z_k(s_k,i =1)은 각각 s_k,i=0일 때와 s_k,i=1일 때 I_k+jQ_k의 실제값을 의미한다. 상기 <수학식 4>를 계산하기 위해서는 2차원 수신신호 R_k에 대해 z_k(s_k,i =0) 및 z_k(s_k,i =1)를 찾아야 한다.In Equation 4 above

And z _k (s _{k, i} = 0) and z _k (s _{k, i} = 1) are the actual values of I _k + jQ _k when s _{k, i} = 0 and s _{k, i} = 1, respectively. Means. In order to calculate Equation 4, z _k (s _{k, i} = 0) and z _k (s _{k, i} = 1) must be found for the two-dimensional received signal R _k .

Equation 4 may be approximated by Equation 5 by the above double minimum matrix method.

는 n_k,i에 대한 부정(negation)을 의미한다. 최단거리 신호점은 R_k의 동위상 신호성분과 직교위상 신호성분의 값의 범위에 의해 결정된다. 상기 <수학식 5>에서 괄호 [ ]속의 첫 번째 항은 다음의 <수학식 6>과 같이 쓸 수 있다.In Equation 5, n _{k, i} means the i-th bit value of the inverse mapping sequence for the signal point at the closest distance to R _k .

Means negation for n _{k, i} . The shortest distance signal point is determined by the range of values of the in-phase signal component and the quadrature signal component of R _k . In Equation 5, the first term in parentheses [] may be written as Equation 6 below.

In Equation 6, U _k and V _k are each represented by {n _{k, m-1} ,... , n _{k, i} ,... , n _{k, 1} , n _{k, 0} } means the in-phase signal component and quadrature signal component of the signal point mapped by. In addition, in Equation 5, the second term in parentheses [] may be written as Equation 7 below.

를 최소화하는 z_k의 역사상 시퀀스 {m_k,m-1, …, m_k,i(=k,i), …, m_k,1, m_k,0}에 의해 사상되는 신호점의 동위상 신호성분과 직교위상 신호성분을 의미한다. 상기 <수학식 6>과 <수학식 7>에 의해 상기 <수학식 5>는 아래의 <수학식 8>과 같이 정리된다.In Equation 7, U _{k, i} and V _{k, i} are respectively

Z _k minimizes the sequence {m _{k, m-1} ,... , m _{k, i (= k, i)} ,.. , m _{k, 1} , m _{k, 0} } means the in-phase signal component and the quadrature signal component of the signal point mapped by. In Equation 6 and Equation 7, Equation 5 is arranged as Equation 8 below.

The process of obtaining the channel decoder input coupling value for the demodulator of the data communication system adopting the modulation scheme of 16QAM according to Equation (8) is as follows.

First, to obtain the two signal components of 16QAM received signal R _k X _k, from the _{Y k {n k, 3,} n k, 2, n k, 1, n k, 0} , and U _k, V _k <Table 1> And <Table 2>. Table 1 shows (n _{k, 3} , n _{k, 2} ) and V for the case _where the quadrature signal component Y _k of the received signal R _k appears in each region for four regions parallel to the horizontal axis shown in FIG. 1. _k is shown, and for convenience, the result values at three boundary values, that is, Y _k = -2a, Y _k = 0, and Y _k = 2a are omitted. Table 2 shows (n _{k, 1} , n _{k, 0} ) and U for the case _where the in-phase signal component X _k of the received signal R _k appears in each region for four regions parallel to the vertical axis shown in FIG. 1. _k is shown, and for convenience, the result values at three boundary values, X _k = -2a, X _k = 0, and X _k = 2a are omitted.

Condition of Y _k (n _{k, 3} , n _{k, 2} ) V _k Y _k > 2a (0, 0) 3a 0 <Y _k <2a (0, 1) a -2a <Y _k <0 (1, 1) -a Y _k <-2a (1, 0) -3a

X _k condition (n _{k, 1} , n _{k, 0} ) U _k X _k > 2a (0, 0) 3a 0 <X _k <2a (0, 1) a -2a <X _k <0 (1, 1) -a X _k <-2a (1, 0) -3a

를 최소화하는 시퀀스 m_k,3, m_k,2, m_k,1, m_k,0을 n_k,3, n_k,2, n_k,1, n_k,0의 함수로 나타낸 결과와, 이에 해당하는 z_k의 동위상 및 직교위상 신호성분인 U_k,i, V_k,i를 보인다.Table 3 below shows each i (where i is one of 0, 1, 2, 3):

A sequence of m _{k, 3} , m _{k, 2} , m _{k, 1} , m _{k, 0} as a function of n _{k, 3} , n _{k, 2} , n _{k, 1} , n _{k, 0} , Corresponding to the in-phase and quadrature signal components of z _k , U _{k, i} and V _{k, i} are shown.

i m _{k, 3} , m _{k, 2} , m _{k, 1} , m _{k, 0} V _{k, i} U _{k, i} 3 n _{k, 3} , 1, n _{k, 1} , n _{k, 0} V _{k, 3} U _k 2 n _{k, 3} , n _{k, 2} , n _{k, 1} , n _{k, 0} V _{k, 2} U _k One n _{k, 3} , n _{k, 2} , n _{k, 1} , 1 V _k U _{k, 1} 0 n _{k, 3} , n _{k, 2} , n _{k, 1} , n _{k, 0} V _k U _{k, 0}

<Table 4><Table5> is _{(n k, 3, n k} , 2) and each for every combination of _{(n k, 1, n k} , 0) < Table 3> found (m _{k, 3} in , m _{k, 2} ) and (m _{k, 1} , m _{k, 0} ) show the values of V _{k, i} and U _{k, i} .

(n _{k, 3} , n _{k, 2} ) V _{k, 3} V _{k, 2} (0, 0) -a a (0, 1) -a 3a (1, 1) a -3a (1, 0) a -a

(n _{k, 1} , n _{k, 0} ) U _{k, 1} U _{k, 0} (0, 0) -a a (0, 1) -a 3a (1, 1) a -3a (1, 0) a -a

<Table 6><Table7> Each <Table 4><Table5> V _{k, i} and U _k, is substituted for _i in the equation (8) the channel decoder input soft value obtained by K '* 4a obtained in It shows the result of being scaled by the ratio of. As a result, when the received signal R _k is received, LLRs satisfying the corresponding conditions can be output as the input coupling values according to Tables 6 and 7. If the channel decoder used in the system is not the Max LogMAP decoder, the process of proportionally expanding the LLRs in Tables 6 and 7 to the inverse of the proportional reduction ratio should be added.

Condition of Y _k Λ (s _{k, 3} ) Λ (s _{k, 2} ) Y _k > 2a 2Y _k -2a Y _k -2a 0 <Y _k <2a Y _k Y _k -2a -2a <Y _k <0 Y _k -Y _k -2a Y _k <-2a 2Y _k + 2a -Y _k -2a

X _k condition Λ (s _{k, 1} ) Λ (s _{k, 0} ) X _k > 2a 2X _k -2a X _k -2a 0 <X _k <2a X _k X _k -2a -2a <X _k <0 X _k -X _k -2a X _k <-2a 2X _k + 2a -X _k -2a

However, when the channel decoder input coupling value is output using the mapping table as shown in <Table 6> or <Table 7>, the demodulator must perform the operation to determine the condition of the received signal. There is a disadvantage that a storage device to be stored is required. This shortcoming can be overcome by replacing the channel decoder input coupling value with an equation having a simpler condition determination operation rather than a mapping table.

For this, the condition judgment expressions shown in Tables 6 and 7 are expressed in different ways, as shown in Tables 8 and 9, respectively. In Tables 8 and 9, ductility values at each of the three boundary values omitted for convenience in Tables 6 and 7 are also considered.

Condition of Y _k Z _k condition Λ (s _{k, 3} ) Λ (s _{k, 2} ) Y _k > = 0 Z _k > = 0 Y _k + (Y _k -2a) Y _k -2a Z _k <0 Y _k Y _k -2a Y _k <0 Z _k > = 0 Y _k -(-Y _k -2a) -Y _k -2a Z _k <0 Y _k -Y _k -2a

X _k condition Z _'k conditions Λ (s _{k, 1} ) Λ (s _{k, 0} ) X _k > = 0 Z ' _k > = 0 X _k + (X _k -2a) X _k -2a Z ' _k <0 X _k X _k -2a X _k <0 Z ' _k > = 0 X _k -(-X _k -2a) -X _k -2a Z ' _k <0 X _k -X _k -2a

In Table 8, Z _k is represented by Equation 9 below, and in Table 9, Z ' _k is represented by Equation 10 below.

In the hardware implementation, when the symbols of X _k , Y _k , Z _k , and Z ' _k can be obtained by the sign bits, respectively, the tables <Table 8> and <Table 9> may be simplified. Table 10 and Table 11 can be obtained. In Tables 10 and 11, MSB (A) is the most significant bit (MSB) indicating the sign of A.

MSB (Y _k ) MSB (Z _k ) Λ (s _{k, 3} ) Λ (s _{k, 2} ) 0 0 Y _k + Z _k Z _k One Y _k Z _k One 0 Y _k -Z _k Z _k One Y _k Z _k

MSB (X _k ) MSB (Z _'k) Λ (s _{k, 1} ) Λ (s _{k, 0} ) 0 0 X _k + Z ' _k Z ' _k One X _k Z ' _k One 0 X _k -Z ' _k Z ' _k One X _k Z ' _k

From Table 10, the ductility values at i = 3 and i = 2, that is, Λ (s _{k, 3} ) and Λ (s _{k, 2} ), are expressed as Equations 11 below.

In addition, from Table 11, the ductility values at i = 1 and i = 0, that is, Λ (s _{k, 1} ) and Λ (s _{k, 0} ) can be expressed as Equations 12 below. .

In the data communication system adopting 16QAM as a modulation method, four coupling values, which are the output of a demodulator for one received signal and the input of a channel decoder, are actually calculated by using the double minimum matrix method of Equation 4 above. It is possible to produce through the simple conditional equations of Equations 9 to 12 above. This process is shown in a flow chart in FIG.

2 illustrates an operation for determining softness values for four demodulation symbols input to a channel decoder in a communication system using a 16QAM modulation scheme according to an embodiment of the present invention. The operation of calculating the ductility value by the double minimum matrix method shown in FIG. 2 can be thought of as two steps. The first process (201 to 209, 211 to 219) determines the parameter A by analyzing the quadrature signal and the value of a, and determines the variable B by analyzing the in-phase signal and the value of a. 210 and 220 output a coupling value by a predetermined equation with the received signal and the variables A and B values obtained in the first process. The operation described below may be performed, for example, in a symbol demodulator of the receiver.

를 계산한다. 여기서, 상기 Z_k, Y_k, X_k 및 a는 실수이다. 그리고, 203단계에서 상기 계산된 결과값 Z_k가 양의 값을 가지는지를 검사한다. 예를 들어, 상기 Z_k, Y_k, X_k 및 a 는 부호비트(sign bit)를 포함하는 디지털 값으로 표현된다. 따라서, 상기 203단계에서는 상기 결과값 Z_k의 최상위비트(즉 부호비트)가 "0"인지를 검사한다. 만일, 상기 결과값 Z_k가 양의 값을 가지는 경우 205단계로 진행하고, 그렇지 않은 경우 209단계로 진행하여 변수 A를 "0"으로 설정한다. Referring to FIG. 2, the symbol demodulator has a minimum distance between signal points in a constellation and a two-dimensional received signal R _k composed of an in-phase component X _k and a quadrature component Y _k in step 201. Using (2a),

Calculate Here, Z _k , Y _k , X _k and a are real numbers. In operation 203, it is checked whether the calculated result value Z _k has a positive value. For example, Z _k , Y _k , X _k, and a are represented by digital values including sign bits. Therefore, in step 203, it is checked whether the most significant bit (that is, the sign bit) of the result value Z _k is “0”. If, the result when the value Z _k has a positive value, and then proceeds to step 205, otherwise the process proceeds to step 209 if it is sets the variable A to "0".

로 판정하고, 세 번째 복조심볼(S_k,2)의 연성값을 Z_k로 판정한다. In step 205, the symbol demodulator checks whether the quadrature component Y _k has a positive value, that is, whether the most significant bit of Y _k is "0". If Y _k has a positive value, the controller proceeds to step 208 to set the variable A to " 1 &quot;; otherwise, proceeds to step 207 to set the variable A to " -1 &quot;. In operation 210, the symbol demodulator determines a softness value of a fourth demodulation symbol S _{k, 3} among demodulation symbols corresponding to the received signal R _k .

Is determined, and the soft value of the third demodulation symbol S _{k, 2} is determined as Z _k .

The foregoing describes the procedure for determining the ductility values for the fourth and third demodulation symbols representing quadrature phase components. Next, the procedure for determining the ductility values of the second and first demodulation symbols representing the in-phase components will be described.

를 계산한다. 그리고, 213단계에서 상기 계산된 결과값 Z'_k가 양의 값을 가지는지 즉, 상기 결과값 Z'_k의 최상위비트(즉 부호비트)가 "0"인지를 검사한다. 만일, 상기 결과값 Z'_k가 양의 값을 가지는 경우 215단계로 진행하고, 그렇지 않은 경우 219단계로 진행하여 변수 B를 "0"으로 설정한다. First, the symbol demodulator is an in-phase component (X _k) and the quadrature component (Y _k) to obtain received 2-D that are generated signal (R _k) and the constellation minimum distance (2a) between two signal points in step 211 have

Calculate In operation 213, it is checked whether the calculated result value Z ′ _k has a positive value, that is, whether the most significant bit (ie, the sign bit) of the result value Z ′ _k is “0”. If, the result when the value Z _'k has a positive value, and then proceeds to step 215, otherwise the process proceeds to step 219 if it is sets the variable B to "0".

로 판정하고, 첫 번째 복조심볼의 연성값을 Z'_k로 판정한다.In step 215, it is checked whether the in-phase component X _k has a positive value. That is, it is checked whether the most significant bit of X _k is "0". If X _k has a positive value, the process proceeds to step 218 and the variable B is set to "1". Otherwise, the variable B is set to "-1". In operation 220, the symbol demodulator _calculates a soft value of a second demodulation symbol S _{k, 3} among demodulation symbols corresponding to the received signal R _k .

Determined by and determines the soft value of the first demodulated symbol to the Z _'k.

Determining the softness values of the fourth and third demodulation symbols (201 to 210) and the process of determining the softness values of the second and first demodulation symbols (211 to 210) may be performed sequentially, at the same time It may also be performed. The combined values of the demodulated symbols thus determined are provided to the channel decoder.

3 is a block diagram of an operation of determining a soft value of demodulation symbols according to an embodiment of the present invention.

Referring to FIG. 3, the quadrature phase signal analyzer 301 has a value a related to the quadrature phase component Y _k of the received signal R _k and the minimum distance 2a between signal points in the constellation. Calculate variable A by the rule. That is, the quadrature-phase signal analyzer 301 determines the variable based on the sign of Z _k (= | Y _k | -2a) and the sign of the quadrature component (Y _k ) as shown in Equation (9). Determine and print A. Then, the first coupling value determiner 302 has the value of the variable A output from the quadrature signal analyzer 301, the quadrature component Y _k , and the minimum distance 2a. Equation 11 is performed to determine and output the coupling values of the fourth and third demodulation symbols.

The in-phase signal analyzer 303 calculates the variable B according to the rules described above with the value a related to the in-phase component X _k of the received signal R _k and the minimum distance 2a between the signal points in the constellation diagram. do. I.e., in-phase signal analyzer 303 as described in the above <Equation 10>, Z _'k on the basis of the sign of the (= | -2a | X _k) code as the in-phase component (Y _k) of Determine and output variable B. Then, the second coupling value determiner 304 has the value of the variable B output from the in-phase signal analyzer 303, the in-phase component (X _k ) and the minimum distance (2a). > To determine and output the ductility value of the second and first demodulation symbols.

4 is a symbol demodulator for determining and outputting a soft value for inputting a channel decoder in a data communication system using 16QAM according to Equation 11 and Equation 12 according to an embodiment of the present invention. Show the device implemented in hardware. The reception signal R _k , in-phase component X _k , quadrature phase component Y _k , Z _k , and Z ′ _{k described below} are digital values including sign bits.

Referring to FIG. 4, the first calculator 401 has a quadrature phase component Y _k of the received signal R _k and a minimum distance 2a between signal points in the constellation diagram. Calculate Z _k according to. The multiplier 402 multiplies &quot; -1 &quot; by the Z _k value from the first calculator 401 to invert and output the sign of the Z _k . The first most significant bit (MSB) extractor 403 extracts the most significant bit of Z _k from the first calculator 401 and outputs it as a selection signal of the first selector 405. The second most significant bit extractor 404 extracts the most significant bit of the quadrature component Y _k and outputs it as a selection signal of the second selector 406.

The first selector 405 receives the Z _k from the first calculator 401 and the "-Z _k " from the first multiplier 402, and receives the first least significant bit extractor 403 from the first most significant bit extractor 403. One of the inputs is selected and output according to the selection signal of. The second selector 406 receives the output of the first selector 405 and “0”, and selects one of the inputs by a selection signal from the second most significant bit extractor 404. The first adder 407 adds the quadrature component Y _k to the output of the second selector 406 to output the ductile value of the fourth demodulation symbol. On the other hand, the Z _k value calculated by the first calculator 401 is output as the soft value of the third demodulation symbol.

The second calculator 411 calculates Z _'k by having the receive input signal (R _k) in-phase component (X _k) to the minimum distance between the signal points in the constellation (2a) of the <Equation 10> To print. Multiplier 402, and outputs by inverting the sign of the second converter 411, the Z 'is multiplied by "-1" to the value _k Z' _k from the. The third MSB extractor 413 and outputs a selection signal of the third selector 415 extracts MSB of the Z _'k from the second calculator 411. The fourth most significant bit extractor 414 extracts the most significant bit of the in-phase component X _k and outputs it as the selection signal of the fourth selector 416.

The third selector 415 receives the Z ′ _k from the second calculator 401 and the “−Z ′ _k ” from the second multiplier 412, and the third most significant bit extractor 413. One of the inputs is selected and output according to the selection signal from &quot; The fourth selector 416 inputs the output of the third selector 415 and "0", and selects and outputs one of the inputs by the selection signal from the fourth least significant bit extractor 414. The second adder 417 adds the in-phase component X _k to the output of the fourth selector 416 to output the ductility value of the second demodulation symbol. Meanwhile, the _Z'k value calculated by the second calculator 411 is output as a soft value of the first demodulation symbol.

Comparing the performance of the conventional ductility value determination and ductility value determination of the present invention is as follows.

If the ductility calculator using the double minimum metric method is implemented as in Equation 4, dozens of square operations and comparison operations are required, whereas the apparatus of FIG. 4 according to an embodiment of the present invention has four calculators (401, 407, 411, 417). It consists of only two multipliers 402, 412, and four multiplexers 405, 406, 415, 416, which has the advantage of reducing the operation time of the demodulator and significantly reducing its complexity. In the following Table 12, when i = {0, 1, 2, 3}, the types of operations used in <Equation 4>, <Equation 11> and <Equation 12>, and their use The recovery was compared.

<Equation 4> <Equation 11>, <Equation 12> Adder 3 * 16 + 4 = 52 pcs
Squarer 2 * 16 = 32 pcs
Comparators 7 * 2 * 4 = 56 pcs 4 adders
2 multipliers
4 multiplexers

<< non-uniform signal constellation >>

Meanwhile, the method described above illustrates a case where the distance between signal points, that is, demodulation symbols, is uniform in the constellation diagram. However, in the case of a communication system in which the channel state is very unstable, such as DVB-T, a nonuniform constellation is used in which the distance between each axis and the signal points closest to the origin is a multiple of the minimum distance between the signal points. This is to cope with the problem that the signal points adjacent to each axis are relatively vulnerable to the error of the channel compared to the other signal points. In the following, the variable α (alpha) is regarded as the distance between the signal points closest to the origin and each axis, and the case where the distance α is 1a, 2a, 4a will be described.

5 shows constellations of 16QAM having the signal points S ₃ , S ₇ , S ₁₁ , and S ₁₅ closest to the origin and the distance α between the axes 1a. In this case, the distance between adjacent signal points is a uniform constellation of 2a. Four demodulation symbols corresponding to the illustrated signal points represent I, Q, I, and Q signal components, respectively. Tables used for the uniform constellation as shown in FIG. 5 are shown in Tables 13 and 14 below.

Condition of Y _k Λ (s _{k, 2} ) Λ (s _{k, 0} ) Y _k > 2a 2Y _k -2a Y _k -2a 0 <Y _k <2a Y _k Y _k -2a -2a <Y _k <0 Y _k -Y _k -2a Y _k <-2a 2Y _k + 2a -Y _k -2a

X _k condition Λ (s _{k, 3} ) Λ (s _{k, 1} ) X _k > 2a 2X _k -2a X _k -2a 0 <X _k <2a X _k X _k -2a -2a <X _k <0 X _k -X _k -2a X _k <-2a 2X _k + 2a -X _k -2a

6 shows constellations of 16QAM having the signal points S ₃ , S ₇ , S ₁₁ , and S ₁₇ closest to the origin and the distance α between each axis. In this case, for example, the distance between the signal point S ₃ closest to the origin and the adjacent signal point S ₇ is 4a, but the distance between the other signal point S ₁ adjacent to S ₃ is 2a. Thus, FIG. 6 is a non-uniform constellation, where the distance between adjacent signal points is 2a or 4a, and the constellation of FIG. 6 may be used, for example, in a poor state of a channel.

FIG. 7 illustrates constellations of 16QAM having the signal points S ₃ , S ₇ , S ₁₁ , and S ₁₇ closest to the origin and the distance α between the axes of 4a. In this case, for example, the distance between the signal point S ₃ closest to the origin and the adjacent signal point S ₇ is 8a, but the distance between the other signal point S ₁ adjacent to the S ₃ is 2a. Thus, FIG. 7 becomes a non-uniform constellation, in which the distance between adjacent signal points is 2a or 8a, and the constellation of FIG. 7 can be used, for example, when the state of the channel is very poor.

The mapping tables used for the nonuniform constellations as shown in FIGS. 6 and 7 are as shown in Tables 15 and 16 below. In other words, when S representing the hierarchical mode is used in accordance with the α value of hierarchical modulation, the history of hierarchical modulation is easily achieved regardless of the hierarchical modulation mode. The hierarchical mode S means a multiple of a representing α, and S is 1, 2, and 4, respectively, when α is 1a, 2a, 4a. In addition, since the operation of multiplying S can be solved by a simple shift of 1 bit or 2 bits, hardware complexity is hardly increased compared to using a uniform constellation.

Condition of Y _k Z _k condition Λ (s _{k, 2} ) Λ (s _{k, 0} ) Y _k > = 0 Z _k > = 0 SY _k + Z _k Z _k Z _k <0 SY _k Z _k Y _k <0 Z _k > = 0 SY _k -Z _k Z _k Z _k <0 SY _k Z _k

X _k condition Z _'k conditions Λ (s _{k, 3} ) Λ (s _{k, 1} ) X _k > = 0 Z ' _k > = 0 SX _k + Z ' _k Z ' _k Z ' _k <0 SX _k Z ' _k X _k <0 Z ' _k > = 0 SX _k -Z ' _k Z ' _k Z ' _k <0 SX _k Z ' _k

In Table 15, Z _k is represented by Equation 13 below, and in Table 16, Z ' _k is represented by Equation 14 below.

인데, α=1a(비-계층모드)일 때 S=1이므로

가 된다. 또한 α=2a(계층모드)일 때 S=2이므로

가 된다.As an example, in Table 15,

Since S = 1 when α = 1a (non-hierarchical mode)

Becomes In addition, when α = 2a (hierarchical mode), S = 2

Becomes

8 shows constellations of 64QAM having the signal points S ₁₂ , S ₂₈ , S ₄₄ , and S ₆₀ closest to the origin and the distance α between the axes 1a. In this case, for example, the distance between the signal point S ₁₂ closest to the origin and the adjacent signal point S ₂₈ is 4a, but the distance between the other signal point S ₁₄ adjacent to the S ₁₂ is equal to 2a. Thus, Figure 8 is a uniform constellation, the distance between adjacent signal points is equal to 2a. Six demodulation symbols corresponding to the illustrated signal points represent I, Q, I, Q, I, and Q signal components, respectively.

Similarly, in the 64QAM system using the constellation of FIG. 8, a soft mapping table as shown in Tables 17 and 18 below is obtained.

Condition of Y _k Λ (s _{k, 4} ) Λ (s _{k, 2} ) Λ (s _{k, 0} ) Y _k > 6a 4Y _k -12a 2Y _k -10a Y _k -6a 4a <Y _k <6a 3Y _k -6a Y _k -4 a Y _k -6a 2a <Y _k <4a 2Y _k -2a Y _k -4 a -Y _k + 2a 0 <Y _k <2a Y _k 2Y _k -6a -Y _k + 2a -2a <Y _k <0 Y _k -2Y _k -6a Y _k + 2a -4a <Y _k <-2a 2Y _k + 2a -Y _k -4a Y _k + 2a -6a <Y _k <-4a 3Y _k + 6a -Y _k -4a -Y _k -6a Y _k <-6 a 4Y _k + 12a -2Y _k -10a -Y _k -6a

X _k condition Λ (s _{k, 5} ) Λ (s _{k, 3} ) Λ (s _{k, 1} ) X _k > 6a 4X _k -12a 2X _k -10a X _k -6a 4a <X _k <6a 3X _k -6a X _k -4a X _k -6a 2a <X _k <4a 2X _k -2a X _k -4a -X _k + 2a 0 <X _k <2a X _k 2X _k -6a -X _k + 2a -2a <X _k <0 X _k -2X _k -6a X _k + 2a -4a <X _k <-2a 2X _k + 2a -X _k -4a X _k + 2a -6a <X _k <-4a 3X _k + 6a -X _k -4a -X _k -6a X _k <-6a 4X _k + 12a -2X _k -10a -X _k -6a

9 shows constellations of 64QAM having the signal points S ₁₂ , S ₂₈ , S ₄₄ , and S ₆₀ closest to the origin and the distance α between each axis. In this case, for example, the distance between the signal point S ₁₂ closest to the origin and the adjacent signal point S ₂₈ is 4a, but the distance between S ₁₂ and another signal point S ₁₄ adjacent to the origin is 2a. Thus, FIG. 9 is a non-uniform constellation, in which the distance between adjacent signal points is 2a or 4a, and the constellation of FIG. 9 may be used, for example, in a poor state of a channel.

FIG. 10 shows constellations of 64QAM having the signal points S ₁₂ , S ₂₈ , S ₄₄ , and S ₆₀ closest to the origin and the distance α between the axes 1a. In this case, for example, the distance between the signal point S ₁₂ closest to the origin and the adjacent signal point S ₂₈ is 8a, but the distance between S ₁₂ and the other signal point S ₁₄ adjacent to the origin is 2a. Thus, FIG. 10 is a non-uniform constellation, in which the distance between adjacent signal points is 2a or 8a, and the constellation of FIG. 6 may be used, for example, in a case where the channel state is very poor.

Then, for all types of maps, the soft maps of Tables 17 and 18 are generalized as shown in Tables 19 and 20 below. This generalized soft time chart allows one piece of hardware to carry out the history of three hierarchical modulation schemes. In this case, the operation of multiplying S can be solved by a simple shift of 1 bit or 2 bits, so the hardware complexity is hardly increased compared to the case of uniform mapping.

MSB ( Y _k ) MSB ( Z _{1 k} ) MSB ( Z _{2 k} ) Λ (s _{k, 4} ) Λ (s _{k, 2} ) Λ (s _{k, 0} ) 0 0 0 SY _k + 3Z _1k Z _1k + Z _2k Z _2k One SY _k + 3Z _1k -Z _2k Z _1k Z _2k One 0 SY _k Z _1k -Z _2k Z _2k One SY _k -Z _2k Z _1k Z _2k One 0 0 SY _k -3Z _1k Z _1k + Z _2k Z _2k One SY _k -3Z _1k + Z _2k Z _1k Z _2k One 0 SY _k Z _1k -Z _2k Z _2k One SY _k + Z _2k Z _1k Z _2k

MSB (X _k ) MSB ( Z ' _{1 k} ) MSB ( Z ' _{2 k} ) Λ (s _{k, 5} ) Λ (s _{k, 3} ) Λ (s _{k, 1} ) 0 0 0 SX _k + 3Z ' _1k Z ' _1k + Z' _2k Z ' _2k One SX _k + 3Z ' _1k -Z' _2k Z ' _1k Z ' _2k One 0 SX _k Z ' _1k -Z' _2k Z ' _2k One SX _k -Z ' _2k Z ' _1k Z ' _2k 0 0 0 SX _k -3Z ' _1k Z ' _1k + Z' _2k Z ' _2k One SX _k -3Z ' _1k + Z' _2k Z ' _1k Z ' _2k One 0 SX _k Z ' _1k -Z' _2k Z ' _2k One SX _k + Z ' _2k Z ' _1k Z ' _2k

In Table 19, Z _1k and Z _2k are shown in Equation 15, and in Table 20, Z ' _1k and Z' _2k are shown in Equation 16 below.

As a result, the flexible mapping table for applying the hierarchical modulation mapping according to the preferred embodiment of the present invention is as described in Tables 15, 16, 19, and 20. The above tables obtain the desired ductility values according to the hierarchical mode of the hierarchical modulation method by applying the S factor to the ductility value determination method of the non-layer modulation method using uniform constellation. The symbol demodulator on the receiving side receives information on the hierarchical mode in order to perform the soft decision, and determines the value of the S factor using the hierarchical mode information.

In other words, S is set to 1 when the non-hierarchical mode in which α is 1a, and the ductility values are calculated as shown in Tables 15 and 16. In the hierarchical mode where α is 2a, S is set to 2 and soft values are calculated as shown in Tables 19 and 20.

FIG. 11 is a flowchart illustrating a history operation for determining soft values for four demodulation symbols input to a channel decoder in a communication system using a 16QAM modulation scheme according to a preferred embodiment of the present invention. The operation of calculating the ductility value by the double minimum matrix method shown in FIG. 11 can be classified into two processes. The first processes 1101 to 1109 and 1111 to 1119 determine the variable A according to the quadrature signal, determine the variable B according to the in-phase signal, and the second processes 1110 and 1120 include the received signal and the first With the values of variables A and B obtained in the process, the soft values for each demodulation symbol are output.

를 계산한다. 여기서, 상기 Z_k, Y_k, X_k 및 a 는 부호비트(sign bit)를 포함하는 디지털 값으로 표현된다. 그리고, 1103단계에서 상기 계산된 결과값 Z_k가 양의 값을 가지는지를 검사한다. 구체적으로, 상기 1103단계에서는 상기 결과값 Z_k의 최상위비트(즉 부호비트)가 "0"인지를 검사한다. 여기서 최상위비트가 0이라 함은 양의 값을 의미하고, 1이라 함은 음의 값을 의미한다. 상기 결과값 Z_k가 양의 값을 가지는 경우 1105단계로 진행하고, 그렇지 않은 경우 1109단계로 진행하여 변수 A를 "0"으로 설정한다. Referring to FIG. 11, in step 1101, the symbol demodulator includes a two-dimensional received signal R _k composed of an in-phase component X _k and a quadrature phase component Y _k and a minimum distance between signal points in a constellation diagram. 2a) and using the S factor representing the hierarchical mode,

Calculate Here, Z _k , Y _k , X _k and a are represented by a digital value including a sign bit. In operation 1103, it is checked whether the calculated result value Z _k has a positive value. Specifically, in step 1103, it is checked whether the most significant bit (ie, the sign bit) of the result value Z _k is "0". In this case, 0 means the most significant bit, and 1 means the negative value. The results when the value Z _k has a positive value, proceeds to step 1105, otherwise proceeds to step 1109 if it is sets the variable A to "0".

로 판정하고, 첫 번째 복조심볼(S_k,0)의 연성값을 Z_k로 판정한다. In step 1105, a symbol demodulator checks whether the quadrature component Y _k has a positive value, that is, whether the most significant bit of Y _k is “0”. If Y _k has a positive value, the process proceeds to step 1108 and the variable A is set to "1". Otherwise, the variable A is set to "-1". In operation 1110, the symbol demodulator determines a ductility value of the third demodulation symbol S _{k, 2} representing a quadrature component among demodulation symbols corresponding to the received signal R _k .

Is determined, and the soft value of the first demodulation symbol S _{k, 0} is determined as Z _k .

The foregoing describes the procedure for determining the ductility values for the third and second demodulation symbols representing quadrature phase components. Next, the procedure for determining the ductility value of the second and first demodulation symbols representing the in-phase component will be described.

를 계산한다. 그리고, 1113단계에서 상기 계산된 결과값 Z'_k가 양의 값을 가지는지 즉, 상기 결과값 Z'_k의 최상위비트(즉 부호비트)가 "0"인지를 검사한다. 만일, 상기 결과값 Z'_k가 양의 값을 가지는 경우 1115단계로 진행하고, 그렇지 않은 경우 1119단계로 진행하여 변수 B를 "0"으로 설정한다. In step 1111, the symbol demodulator displays the two-dimensional received signal R _k composed of an in-phase component (X _k ) and a quadrature component (Y _k ), and the minimum distance (2a) and hierarchical mode between two signal points in constellation. With an A argument that represents

Calculate Then, a check to see if "0", that of the _k is a positive value that is, the result value Z, the computed result value Z in step 1113. The most significant bit (i.e. the sign bit) of the _k. If, the result when the value Z _'k has a positive value, and then proceeds to step 1115, otherwise it proceeds to step 1119 if it is sets the variable B to "0".

로 판정하고, 두 번째 복조심 볼의 연성값을 Z'_k로 판정한다.In step 1115, it is checked whether the in-phase component X _k has a positive value. That is, it is checked whether the most significant bit of X _k is "0". If X _k has a positive value, the controller 1 proceeds to step 1118 to set the variable B to "1". Otherwise, the controller proceeds to step 1117 to set the variable B to "-1". In operation 1120, the symbol demodulator determines a ductility value of a fourth demodulation symbol S _{k, 3} representing an in-phase component among demodulation symbols corresponding to the received signal R _k .

Determined by and determines the soft value of the second clothing careful on Z _'k.

When the procedure for determining the ductility value of the 16QAM demodulation symbols shown in FIG. 11 is represented by a formula, Equations 17 and 18 may be represented.

Determining the softness value of the demodulation symbols representing the quadrature component (1101 to 1110) and determining the softness value of the demodulation symbols representing the in-phase component (1111 to 1110) may be performed sequentially or at the same time It may also be performed. The combined values of the demodulated symbols thus determined are provided to the channel decoder. A channel decoder restores the demodulation symbols by the soft values.

12A and 12B are flowcharts illustrating a history operation for determining soft values for four demodulation symbols input to a channel decoder in a communication system using a 64QAM modulation scheme according to a preferred embodiment of the present invention. The operation of calculating the ductility value by the double minimum matrix method shown in Figs. 12A and 12B can be considered largely divided into two processes. The first processes (1201 to 1229, 1241 to 1269) determine the necessary parameters according to the quadrature signal and the in-phase signal, and the second process (1231 to 1271) has the received signal and the variable values obtained in the first process. Outputs the coupling value for each demodulation symbol.

Referring to FIG. 12A, the symbol demodulator positively _affects the quadrature phase component Y _k of the two-dimensional received signal R _{k including the} in-phase component X _k and the quadrature component Y _k in step 1201. Check if it has the value of. Specifically, in step 1201, it is checked whether the most significant bit (that is, the sign bit) of _Yk is "0". In this case, 0 means the most significant bit, and 1 means the negative value. If Y _k has a positive value, the process proceeds to step 1215 to set the variable c to "1", otherwise proceeds to step 1213 to set the variable c to "-1".

을 계산한다. 여기서 S*a=α(alpha)는 상기 성상도에서 원점에 가장 가까운 신호점들과 각 축 간 거리를 의미한다. 상기 계산된 제1 결과값 Z_1k는 1205단계와 1207단계로 넘겨진다. 상기 1205단계에서 상기 Z_1k의 최상위비트에 따라 상기 Z_1k가 양의 값을 가지는지를 검사한다. 상기 Z_1k가 양의 값을 가지는 경우 1217단계로 진행하여 변수 A를 "3"으로 설정하고, 그렇지 않은 경우 1219단계로 진행하여 상기 변수 A를 "0"으로 설정한다.Further, in step 1203, the symbol demodulator uses the quadrature component Y _k of the received signal R _k and the minimum distance 2a between the signal points in the constellation and the hierarchical mode factor S.

. S * a = α (alpha) means the distance between each axis and the signal points closest to the origin in the constellation. The calculated first result value Z _1k is passed to steps 1205 and 1207. In the step 1205 determines whether the above Z _1k has a positive value according to the MSB of the Z _1k. If Z _1k has a positive value, the process proceeds to step 1217 and the variable A is set to “3”. Otherwise, the variable A is set to “0”.

을 계산한다. 그리고, 1209단계에서 상기 계산된 제2 결과값 Z_2k의 최상위비트에 따라 상기 Z_2k가 양의 값을 가지는지를 검사한다. 상기 Z_2k가 양의 값을 가지는 경우 1221단계로 진행하여 변수 B를 "0"으로 설정하고, 그렇지 않은 경우 1223단계와 1225단계로 진행하여 상기 변수 B를 "-1"로 설정하고 변수 γ(gamma)를 "0"으로 설정한다. 상기 1209단계에서 상기 Z_2k가 양의 값을 가지는 경우, 심볼복조기는 1211단계에서 상기 Z_1k의 최상위비트를 다시 검사한다. 상기 1211단계에서 상기 Z_1k가 양의 값을 가지는 경우 1227단계에서 상기 변수 γ를 "1"로 설정하고, 그렇지 않은 경우 1229단계에서 상기 변수 γ를 "-1"로 설정한다.In step 1207, a symbol demodulator uses Z _1k and 2a.

. In operation 1209, it is checked whether Z _2k has a positive value according to the most significant bit of the calculated second result value Z _2k . If Z _2k has a positive value, the process proceeds to step 1221 to set the variable B to "0". Otherwise, the process proceeds to step 1223 and 1225 to set the variable B to "-1" and the variable γ ( gamma) is set to "0". If Z _2k has a positive value in step 1209, the symbol demodulator _rechecks the most significant bit of Z _1k in step 1211. If Z _1k has a positive value in step 1211, the variable γ is set to “1” in step 1227, and otherwise, the variable γ is set to “−1” in step 1229.

로 판정하고, 세 번째 복조심볼(S_k,2)의 연성값을

로 판정하며, 첫 번째 복조심볼(S_k,0)의 연성값을 Z_2k로 판정한다. In operation 1231, the symbol demodulator determines a softness value of a fifth demodulation symbol S _{k, 4} among demodulation symbols corresponding to the received signal R _k .

And the ductility value of the third demodulation symbol (S _{k, 2} )

The soft value of the first demodulation symbol S _{k, 0} is determined as Z _2k .

The above has described the procedure for determining the ductility value for demodulation symbols representing quadrature phase components. Next, a procedure of determining the ductility value of demodulation symbols representing in-phase components will be described with reference to FIG. 12B.

Referring to FIG. 12b, the symbol demodulator in-phase component in the 1241 phase (X _k) and the quadrature component (Y _k) the behavior of the 2-dimensional received signal (R _k) consisting of a phase component (X _k), the amount Check if it has the value of. Specifically, in step 1241, it is checked whether the most significant bit (ie, the sign bit) of X _k is "0". In this case, 0 means the most significant bit, and 1 means the negative value. If X _k has a positive value, the process proceeds to step 1255 and the variable c 'is set to "1". Otherwise, the variable c' is set to "-1".

을 계산한다. 여기서 S*a=α(alpha)는 상기 성상도에서 원점에 가장 가까운 신호점들과 각 축 간 거리를 의미한다. 상기 계산된 제1 결과값 Z'_1k는 1245단계와 1247단계로 넘겨진다. 상기 1245단계에서 상기 Z'_1k의 최상위비트에 따라 상기 Z'_1k가 양의 값을 가지는지를 검사한다. 상기 Z'_1k가 양의 값을 가지는 경우 1257단계로 진행하여 변수 A'를 "3"으로 설정하고, 그렇지 않은 경우 1259단계로 진행하여 상기 변수 A'를 "0"으로 설정한다.Further, in step 1243, the symbol demodulator uses the hierarchical mode factor S and the minimum distance 2a between the signal points in the constellation and the in-phase component X _k of the received signal R _k .

. S * a = α (alpha) means the distance between each axis and the signal points closest to the origin in the constellation. The calculated first result Z ′ _1k is passed to steps 1245 and 1247. Checks whether, according to the most significant bit of the Z _{1k, 1k} have the Z having a positive value in the step 1245. If Z ' _1k has a positive value, the process proceeds to step 1257 and the variable A' is set to "3". Otherwise, the variable A 'is set to "0".

을 계산한다. 그리고, 1249단계에서 상기 계산된 제2 결과값 Z'_2k의 최상위비트에 따라 상기 Z'_2k가 양의 값을 가지는지를 검사한다. 상기 Z'_2k가 양의 값을 가지는 경우 1261단계로 진행하여 변수 B'를 "0"으로 설정하고, 그렇지 않은 경우 1263단계와 1265단계로 진행하여 상기 변수 B'를 "-1"로 설정하고 변수 γ'(gamma)를 "0"으로 설정한다. 상기 1249단계에서 상기 Z'_2k가 양의 값을 가지는 경우, 심볼복조기는 1251단계에서 상기 Z'_1k의 최상위비트를 다시 검사한다. 상기 1251단계에서 상기 Z'_1k가 양의 값을 가지는 경우 1267단계에서 상기 변수 γ'를 "1"로 설정하고, 그렇지 않은 경우 1269단계에서 상기 변수 γ'를 "-1"로 설정한다.In step 1247, the symbol demodulator uses Z ' _1k and 2a.

. In operation 1249, it is checked whether the Z ′ _2k has a positive value according to the most significant bit of the calculated second result value Z ′ _2k . If Z ' _2k has a positive value, go to step 1261 to set variable B' to "0". Otherwise, go to step 1263 and 1265 to set variable B 'to "-1". Set the variable γ '(gamma) to "0". If the Z ' _2k has a positive value in step 1249, the symbol demodulator _rechecks the most significant bit of the Z' _1k in step 1251. In step 1251, when the Z ' _1k has a positive value, in step 1267, the variable γ' is set to "1". Otherwise, in step 1269, the variable γ 'is set to "-1".

로 판정하고, 네 번째 복조심볼(S_k,3)의 연성값을

로 판정하며, 두 번째 복조심볼(S_k,1)의 연성값을 Z'_2k로 판정한다. In operation 1271, the symbol demodulator determines a softness value of a sixth demodulation symbol S _{k, 5} among demodulation symbols corresponding to the received signal R _k .

And the ductility value of the fourth demodulation symbol (S _{k, 3} )

The soft value of the second demodulation symbol S _{k, 1} is determined as Z ' _2k .

The procedure for determining the ductility value of the 16QAM demodulation symbols shown in FIG. 11 is represented by Equations 19 and 20.

13 is a symbol demodulator for determining and outputting a coupling value for inputting a channel decoder in a data communication system using 16QAM according to Equation (13) or (14) according to an embodiment of the present invention. Show the device implemented in hardware. In the following, only portions for determining the ductility values for the demodulation symbols corresponding to the in-phase component (X _k ) or the quadrature component (Y _k ) are shown. Hereinafter, the structure and operation of the quadrature component (Y _k ) will be described, but the same structure and description also apply to the in-phase component (X _k ). The reception signal R _k , the in-phase component X _k , the quadrature component Y _k , the variable Z _k , and the variable Z ' _{k described below} are digital values including a sign bit. In the following description, the symbol index k is omitted.

Referring to FIG. 13, an absolute value (ABS) calculator 1319 is an absolute value of one phase component (Y or X, Y will be described below) of an input signal R. Compute and print the value | Y |. The first calculator 1321 subtracts the minimum distance 2a between signal points in the constellation and (S + 1) a 1301 according to the hierarchical mode factor S from the absolute value | Y | of the quadrature component. Outputs Z (= | Y |-(S + 1) a). The multiplier 1323 multiplies the Z value from the first calculator 1321 by " -1 " to invert and output the sign of Z. The first most significant bit (MSB) extractor 1311 extracts the most significant bit of the quadrature component Y and outputs it as a first selection signal for the first selector 1317. The second most significant bit extractor 1313 extracts the most significant bit of Z and outputs it as a second selection signal for the second selector 1315.

The first selector 1317 receives the Z from the first calculator 1321 and the -Z from the multiplier 1323, and the first select signal from the first most significant bit extractor 1311. Selects and outputs one of the inputs. Specifically, Z is selected when the first selection signal is 0, and -Z is selected when the first selection signal is 1. The second selector 1315 receives the output from the first selector 1317 and "0", and receives one of the inputs by the second select signal from the second most significant bit extractor 1312. Select and print. Specifically, when the second selection signal is 0, the output of the first selector 1317 is selected, and when the second selection signal is 1, "0" is selected.

The bit shifter 1305 receives the quadrature component (Y) 1303, and outputs SY by bypassing the Y or by shifting 1 bit or 2 bits according to S representing the hierarchical mode. Specifically, if S is 1, the Y is bypassed, if 2, 1 bit is shifted, and if 4, 2 bit is shifted. The second calculator 1307 adds the output of the second selector 1315 to 3Y from the bit shifter 1305 and outputs the soft value 1309 of the third demodulation symbol. On the other hand, the Z value calculated by the first calculator 1321 is output as the soft value 1325 of the first demodulation symbol. Similarly, the ductility values of the fourth and second demodulation symbols for the in-phase component X are obtained.

14 is a symbol demodulator for determining and outputting a coupling value for inputting to a channel decoder in a data communication system using 64QAM according to Equation 15 or Equation 16 according to a preferred embodiment of the present invention. Show the device implemented in hardware. In the following, only portions for determining the ductility values for the demodulation symbols corresponding to the in-phase component (X _k ) or the quadrature component (Y _k ) are shown. Hereinafter, the structure and operation of the quadrature component (Y _k ) will be described, but the same structure and description also apply to the in-phase component (X _k ). The reception signal (R _k ), in-phase component (X _k ), quadrature component (Y _k ), variable Z _1k , variable Z ' _k , variable Z _2k and variable Z' _{2k described below} are digital including a sign bit. Is the value. In the following description, the symbol index k is omitted.

Referring to FIG. 14, the first absolute value ABS calculator 1423 includes an absolute value of one phase component (Y or X, Y will be described below) of the received signal R. Calculate and print | Y |. The first calculator 1425 subtracts the minimum distance 2a between signal points in the constellation and (S + 1) a 1401 according to the hierarchical mode factor S from the absolute value | Y | of the quadrature component. Outputs Z ₁ (= | Y |-(S + 1) a). The first multiplier 1433 multiplies the value of Z ₁ from the first calculator 1425 by "3" and outputs 3Z ₁ . The second multiplier 1437 multiplies the 3Z ₁ from the first multiplier 1433 by "-1" and outputs -3Z ₁ . The first most significant bit (MSB) extractor 1413 extracts the most significant bit of the quadrature component Y and outputs the first most significant bit for the first selector 1415 and the fifth selector 1418. The second most significant bit extractor 1439 extracts the most significant bit of Z ₁ from the first calculator 1425 and outputs it as a second selection signal for the second selector 1417 and the third selector 1443.

The first selector 1415 receives the 3Z ₁ from the first multiplier 1433 and the −3Z ₁ from the second multiplier 1437 and receives the 3Z ₁ from the first most significant bit extractor 1413. One of the inputs is selected and output by the first selection signal. In detail, when the first selection signal is 0, the 3Z ₁ is selected. When the first selection signal is 1, the -3Z ₁ is selected. The second selector 1417 receives an output from the first selector 1415 and a "0", and one of the inputs is generated by the second select signal from the second most significant bit extractor 1439. Select to print. Specifically, when the second selection signal is 0, the output of the first selector 1415 is selected, and when the second selection signal is 1, the “0” is selected.

The bit shifter 1405 receives the quadrature component (Y) 1403, and outputs SY by bypassing the Y or by shifting 1 bit or 2 bits according to the value of the S factor indicating the hierarchical mode. Specifically, if S is 1, the Y is bypassed, if 2, 1 bit is shifted, and if 4, 2 bit is shifted. The third calculator 1407 adds and outputs the output of the second selector 1417 to 3Y from the bit shifter 1405.

The Z ₁ from the first calculator 1425 is input to a second absolute value calculator 1743. The second absolute value calculator (1427) is an absolute value of the Z ₁ |, and outputs the calculation of | Z _1. The second calculator 1431 subtracts the minimum distances 2a and 1429 between signal points from the constellation to Z ₁ | to Z ₂ (= | (| Y |-(S + 1) a) | Output -2a) The third multiplier 1441 multiplies the value of Z ₂ from the second calculator 1431 by "-1" and outputs -Z ₂ . The third most significant bit extractor 1449 extracts the most significant bit of Z ₂ and outputs it as a third selection signal for the fourth selector 1445 and the sixth selector 1421.

The third selector 1443 receives the Z ₂ from the second calculator 1431 and the -Z ₂ from the third multiplier 1441, and receives the _first from the second most significant bit extractor 1439. 2, one of the inputs is selected and output by the selection signal. In more detail, when the second selection signal is 0, Z ₂ is selected. When the second selection signal is 1, -Z ₂ is selected. The fourth selector 1445 receives an output from the third selector 1443 and "0", selects one of the inputs by the third selection signal, and outputs the selected one. In detail, when the third selection signal is 0, the output of the third selector 1443 is selected, and when the third selection signal is 1, the “0” is selected.

The Z ₂ from the second calculator 1431 is input to a fourth multiplier 1418. The fourth multiplier 1418 multiplies Z ₂ by "-1" to output -Z ₂ . The fifth selector 1418 receives the Z ₂ from the second calculator 1431 and the -Z ₂ from the fourth multiplier 1418 and receives the first from the first most significant bit extractor 1413. 1 One of the inputs is selected and output by the selection signal. In more detail, if the first selection signal is 0, -Z ₂ is selected, and if the second selection signal is 1, Z ₂ is selected. The sixth selector 1421 receives an output from the fifth selector 1418 and a "0", and receives one of the inputs by the third selection signal from the third most significant bit extractor 1449. Select and print. In detail, when the third selection signal is 0, "0" is selected. When the third selection signal is 1, the output of the fifth selector 1418 is selected.

The fifth calculator 1409 adds the output from the sixth selector 1421 to the output from the third calculator 1407 and outputs the soft value 1411 of the fifth demodulation symbol. The fourth calculator 1447 adds the output from the fourth selector 1445 to the Z ₁ from the first calculator 1425 and outputs the coupling value 1451 of the third demodulation symbol. On the other hand, the Z ₂ value calculated by the second calculator 1431 is output as the soft value 1453 of the first demodulation symbol. Similarly, the ductility values of the sixth, fourth and second demodulation symbols for the in-phase component X are obtained.

The advanced data communication system can adaptively select one of a plurality of modulation schemes (MS) according to various requirements such as channel conditions, amount of data to be transmitted and service priority. In the integrated symbol demodulator of such a system, two to six soft values according to, for example, QPSK, 16QAM, 64QAM, are determined according to the MS signal indicating the modulation scheme.

FIG. 15 shows a hardware-implemented integrated symbol demodulator for determining and outputting a soft value for input to a channel decoder in a data communication system using QPSK, 16QAM, and 64QAM according to a preferred embodiment of the present invention. In the following, only portions for determining the ductility values for the demodulation symbols corresponding to the in-phase component (X _k ) or the quadrature component (Y _k ) are shown. Hereinafter, the structure and operation of the quadrature component (Y _k ) will be described, but the same structure and description also apply to the in-phase component (X _k ). The reception signal (R _k ), in-phase component (X _k ), quadrature component (Y _k ), variable Z _1k , variable Z ' _k , variable Z _2k and variable Z' _{2k described below} are digital including a sign bit. Value. In the following description, the symbol index k is omitted. When comparing FIG. 15 with FIG. 14, three selectors 1511, 1535, and 1539 using the MS mode signal are added as main differences. The MS mode signal represents QPSK ("0"), 16QAM ("1"), and 64QAM ("2).

Referring to FIG. 15, the first absolute value ABS calculator 1525 is an absolute value of one phase component (Y or X, Y will be described below) of the received signal R. Calculate and print | Y |. The first calculator 1527 subtracts the minimum distance 2a between signal points in the constellation and (S + 1) a 1501 according to the hierarchical mode factor S from the absolute value | Y | of the quadrature component. Outputs Z ₁ (= | Y |-(S + 1) a). The first multiplier 1537 multiplies the value of Z ₁ from the first calculator 1527 by "3" and outputs 3Z ₁ . A seventh selector 1539 receives the Z ₁ from the first calculator 1527 and the 3Z ₁ from the first multiplier 1537 and selects one of the inputs by the MS mode signal. Output Specifically, when the MS mode signal is "1" representing 16QAM, the Z ₁ is selected. If the MS mode signal is "2" representing 64QAM, the 3Z ₁ is selected. If the MS mode signal is "0", it is don't care. Then, the output of the seventh selector 1539 becomes Z ₁ or 3Z ₁ .

The second multiplier 1541 multiplies the output from the seventh selector 1539 by "-1" to output -Z ₁ or -3Z ₁ . The first most significant bit (MSB) extractor 1515 extracts the most significant bit of the quadrature component Y and outputs the first most significant bit for the first selector 1517 and the fifth selector 1521. The second most significant bit extractor 1543 extracts the most significant bit of Z ₁ from the first calculator 1527 and outputs it as a second selection signal for the second selector 1519 and the third selector 1545. .

The first selector 1517 receives the output of the seventh selector 1539 and the output of the second multiplier 1541, and the first selector 1517 receives the first select signal from the first most significant bit extractor 1515. Select one of the inputs and output it. Specifically, when the first selection signal is 0, the output of the seventh selector 1539 is selected. When the first selection signal is 1, the output of the second multiplier 1541 is selected. The second selector 1519 receives an output from the first selector 1517 and a "0", and receives one of the inputs by the second select signal from the second most significant bit extractor 1543. Select and print. Specifically, when the second selection signal is 0, the output of the first selector 1517 is selected, and when the second selection signal is 1, the “0” is selected.

The bit shifter 1505 receives the quadrature component (Y) 1503 and outputs SY by bypassing the Y or by shifting 1 bit or 2 bits according to the value of the S factor indicating the hierarchical mode. Specifically, if S is 1, the Y is bypassed, if 2, 1 bit is shifted, and if 4, 2 bit is shifted. The third calculator 1507 adds and outputs the output of the second selector 1519 to 3Y from the bit shifter 1505.

The Z ₁ from the first calculator 1527 is input to a second absolute value calculator 1529. The second absolute value calculator (1529) is an absolute value of the Z ₁ |, and outputs the calculation of | Z _1. The second calculator 1533 subtracts the minimum distances 2a and 1531 between the signal points in the constellation from the Z ₁ | to Z ₂ (= | (| Y |-(S + 1) a) | Output -2a) The eighth selector 1535 receives the Z ₁ from the first calculator 1527 and the Z ₂ from the second calculator 1533 and selects one of the inputs by the MS mode signal. Output Specifically, when the MS mode signal is "1" representing 16QAM, the Z ₁ is selected. If the MS mode signal is "2" representing 64QAM, the Z ₂ is selected. If the MS mode signal is "0", it is don't care. The output of the eighth selector 1539 is then Z ₁ or Z ₂ .

The third multiplier 1553 multiplies the output from the eighth selector 1535 by "-1" to output -Z ₁ or -Z ₂ . The third most significant bit extractor 1551 extracts the most significant bit of Z ₂ and outputs it as a third selection signal for the fourth selector 1547 and the sixth selector 1523.

The third selector 1545 receives an output of the eighth selector 1535 and an output of the third multiplier 1553, and receives the input by a second selection signal from the second most significant bit extractor 1543. Select and print one of these. In detail, when the second selection signal is 0, the output of the eighth selector 1535 is selected. When the second selection signal is 1, the output of the third multiplier 1553 is selected. The fourth selector 1547 receives an output from the third selector 1545 and "0", selects one of the inputs by the third selection signal, and outputs the selected one. Specifically, when the third selection signal is 0, the output of the third selector 1545 is selected, and when the third selection signal is 1, the “0” is selected.

The Z ₁ or Z ₂ from the eighth selector 1535 is input to a fourth multiplier 1555. The fourth multiplier 1555 multiplies the output of the eighth selector 1535 by "-1" to output -Z ₁ or -Z ₂ . The fifth selector 1521 receives an output from the eighth selector 1535 and an output from the fourth multiplier 1555, and receives a first select signal from the first most significant bit extractor 1515. One of the inputs is selected and output. In detail, when the first selection signal is 0, the output of the fourth multiplier 1555 is selected. When the second selection signal is 1, the output of the eighth selector 1535 is selected. The sixth selector 1523 receives an output from the fifth selector 1521 and "0", and receives one of the inputs by the third select signal from the third most significant bit extractor 1551. Select and print. In detail, when the third selection signal is 0, “0” is selected. When the third selection signal is 1, the output of the fifth selector 1521 is selected.

The fifth calculator 1509 adds and outputs the output from the sixth selector 1523 to the output from the third calculator 1507. The ninth selector 1511 receives an output of the quadrature component (Y) 1503 and the fifth calculator 1509, selects one of the inputs by the MS mode signal, and outputs the selected one. Specifically, the quadrature phase component (Y) 1503 is selected if the MS mode signal is "0" representing QPSK, and if the MS mode signal is "1" representing 16QAM or "2" representing 64QAM, 5 Select the output of the calculator (1509). On the other hand, the fourth calculator 1549 adds and outputs the output from the fourth selector 1547 to the Z ₁ from the first calculator 1549.

When QPSK is used, the output 1513 of the ninth selector 1511 becomes the soft value of the first demodulation symbol related to the quadrature component. Similarly, the ductility value of the second demodulation symbol related to the in-phase component is obtained.

When 16QAM is used, the output 1513 of the ninth selector 1511 is a soft value of a third demodulation symbol related to the quadrature component, and the output 1559 of the eighth selector 1535 is quadrature It is the ductility value of the first demodulation symbol associated with the component. Similarly, the ductility values of the fourth and second demodulation symbols for in-phase components are obtained.

When 64QAM is used, the output 1513 of the ninth selector 1511 becomes the soft value of the fifth demodulation symbol related to the quadrature component, and the output 1557 of the fourth calculator 1549 is quadrature. It is a soft value of the third demodulation symbol related to the component, and the output 1559 of the eighth selector 1535 is a soft value of the first demodulation symbol related to the quadrature component. Similarly, the ductility values of the sixth, fourth and second demodulation symbols for in-phase components are obtained.

13 and 14 illustrate the operations of Tables 15, 16, 19, and 20 described above in block diagram form. Referring to FIGS. 13 and 14, the hierarchical mode factor S controls the bit shifters 1305 and 1405 and the calculators 1321 and 1425 to perform the transition operation and the addition operation for the case where α is 1a, 2a, or 4a. . Since the received signal is composed of an in-phase component and a quadrature component, it can be seen that two circuits as shown in FIGS. 13 and 14 determine soft values for the in-phase component and the quadrature component of the received signal.

Similarly, FIG. 15 shows a circuit for any one phase component of a symbol demodulator that can be used in QPSK, 16QAM, and 64QAM. When the modulation method information and the hierarchical mode information are input, soft values corresponding thereto are generated and output. In FIG. 15, the uppermost output 1513 is a high priority stream, and the lower and lower outputs 1557 and 1559 are a low priority stream. The three outputs 1513, 1557, 1559 of FIG. 15 are used via normalization, respectively, and are not shown separately here.

While the present invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiments, but is capable of various modifications within the scope of the invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined not only by the scope of the following claims, but also by those equivalent to the scope of the claims.

In the present invention operating as described in detail above, the effects obtained by the representative ones of the disclosed inventions will be briefly described as follows.

Industrial Applicability The present invention can design an efficient, low complexity flexible phase inversion machine. In addition, it is possible to implement all three modulation schemes and the hierarchical mode in each modulation scheme by adding only a few operations without requiring separate circuits separately for various conditions.

Claims (13)

16QAM (16-ary) for receiving k-th received signal R _k composed of quadrature phase component Y _k and in-phase component X _k and determining coupling values for decoding of received signal R _k (X _k , Y _k ) In Quadrature Amplitude Modulation demodulation device, Of the four demodulation symbols, using the minimum distance (2a) between the signal points in the 16QAM constellation, the signal point closest to the origin in the 16QAM constellation, the distance (α) between each axis, and the quadrature component Y _k . A first ductility value determining unit for determining ductility values Λ (S _k , ₂ ) and Λ (S _k , ₀ ) of two demodulation symbols related to the quadrature component Y _k using the following equation; By using the minimum distance 2a, the distance α, and the in-phase component X _k , the coupling values Λ (S _k) of two demodulation symbols related to the in-phase component X _k among the four demodulation symbols ₃ ) and a second softness value determining unit for determining Λ (S _k , ₁ )) by using the following equation.

Here, "2a" is the minimum distance between signal points in the 16QAM constellation, and "S" represents a multiple of the a for the distance to each axis of the signal point closest to the origin in the 16QAM constellation ( α = Sa). The method of claim 1, wherein the first ductility value determination unit, A bit shifter for shifting the quadrature component Y _k by 0, 1, or 2 bits according to the value of S; The Z _k is calculated with the minimum distances 2a and S between the quadrature component Y _k and the signal points, and the Z _k is output as the coupling value Λ (s _{k, 0} ) of the first demodulation symbol. A first calculator, And a first selector for selecting and outputting one of said input in accordance with the Z _k and an inverted value of the input receives the Z _k, the most significant bit (MSB) of the quadrature-phase component Y _k from the first calculator, A second selector which receives an output of the first selector and a value of "0", selects and outputs one of the inputs according to the most significant bit of Z _k ; And a second calculator for adding the output of the second selector and the output of the bit shifter to output a coupling value Λ (s _{k, 2} ) of a third demodulation symbol. The method of claim 1, wherein the second ductility value determination unit, A bit shifter for shifting the in-phase component X _k by 0, 1, or 2 bits according to the value of S; The in-phase component X _k and the signal point of minimum distance 2a and the soft values _{(Λ (s k, 1)} ) of the Z 'calculate _k, and the Z' _k to the second demodulated symbol has the S between the A first calculator to output, And a first selector which receives the inverse of the input and the Z _k Z _k from the first calculator, and outputs the selected one of said input according to the MSB of the in-phase component X _k, And a second selector which receives the input and the output "0" value of the first selector, selecting and outputting one of said input according to the MSB of the Z _'k, And a second calculator for adding the output of the second selector and the output of the bit shifter to output a coupling value (Λ (s _{k, 3} )) of a fourth demodulation symbol. The k-th received signal R _k (X _k , Y _k ) consisting of quadrature component Y _k and in-phase component X _k is input, and the coupling values for decoding of the received signal R _k (X _k , Y _k ) are input. In the 16-ary Quadrature Amplitude Modulation (16QAM) demodulation method to determine, Of the four demodulation symbols, using the minimum distance (2a) between the signal points in the 16QAM constellation, the signal point closest to the origin in the 16QAM constellation, the distance (α) between each axis, and the quadrature component Y _k . Determining the coupling values (Λ (S _k , ₂ ), Λ (S _k , ₀ )) of two demodulation symbols related to the quadrature component Y _k ; By using the minimum distance 2a, the distance α, and the in-phase component X _k , the coupling values Λ (S _k) of two demodulation symbols related to the in-phase component X _k among the four demodulation symbols , ₃ ), Λ (S _k , ₁ )).

Here, "2a" is the minimum distance between signal points in the 16QAM constellation, and "S" represents a multiple of the a for the distance to each axis of the signal point closest to the origin in the 16QAM constellation ( α = Sa). The method of claim 4, wherein the determining of the ductility values associated with the quadrature component Y _k comprises: The Z _k is calculated with the minimum distances 2a and S between the quadrature component Y _k and the signal points, and the Z _k is output as the coupling value Λ (s _{k, 0} ) of the first demodulation symbol. Process, Determining the variable A to 0 when the most significant bit of Z _k is 1; Determining the variable A as -1 when the most significant bit of Z _k is 0 and the most significant bit of Y _k is 1; Determining the variable A as 1 when the most significant bit of Z _k is 0 and the most significant bit of Y _k is 0; Calculating AZ _k by multiplying Z _k by the variable A; Calculating SY _k by multiplying the value of S by Y _k ; And adding the AZ _k to the SY _k to determine a ductility value Λ (s _{k, 2} ) of a third demodulation symbol. The method of claim 4, wherein the determining of ductility values related to the in-phase component X _k comprises: As the in-phase component Y _k and the signal point of minimum distance 2a and have the S 'and calculates _k, the Z' wherein Z soft value _{(Λ (s k, 1)} ) of a second demodulated symbol a _k between Printing process, If the MSB of the Z _'k is 1, the determining of the variable B to zero and, If the Z _'k of the most significant bit is zero and the MSB of the X _k is 1, the determining of the variable B to -1, and, If the most significant bit of the Z _'k is zero and the MSB of the X _k is zero, the determining of the variables B 1 and, Calculating the BZ _k is multiplied by the variable B in the Z _'k and, Calculating SX _k by multiplying X _k by the value of S; Demodulating method of the SX _k characterized in that it comprises the step of determining a soft value _{(Λ (s k, 3)} ) of a fourth demodulated symbol by adding the BZ _'k. A k-th received signal R _k (X _k , Y _k ) consisting of quadrature component Y _k and in-phase component X _k is input, and the coupling values for decoding of the received signal R _k (X _k , Y _k ) are received. In the 64-ary quadrature amplitude modulation (64QAM) demodulation device to determine, Of the six demodulation symbols, using the minimum distance (2a) between the signal points in the 64QAM constellation, the signal point closest to the origin in the 64QAM constellation, the distance (α) between each axis, and the quadrature component Y _k . A first value for determining the coupling values (Λ (S _k , ₄ ), Λ (S _k , ₂ ), Λ (S _k , ₀ )) of the three demodulation symbols related to the quadrature component Y _k using the following equation: Ductility determination unit, By using the minimum distance 2a and the distance α and the in-phase component X _k , the coupling values Λ (S _k of three demodulation symbols related to the in-phase component X _k among the six demodulation symbols , ₅ ), Λ (S _k , ₃ ), Λ (S _k , ₁ )) and a second softness value determination unit for determining using the following equation.

Here, "2a" is the minimum distance between signal points in the 16QAM constellation, and "S" represents a multiple of the a for the distance to each axis of the signal point closest to the origin in the 16QAM constellation ( α = Sa). The method of claim 7, wherein the first ductility value determination unit, A bit shifter for shifting the quadrature component Y _k by 0 bits, 1 bit, or 2 bits according to the value of S; A first calculator for calculating the Z _1k with the quadrature phase component Y _k and the minimum distances 2a and S; A second calculator for calculating Z _2k with the Z _1k and the minimum distance 2a from the first calculator and outputting the Z _2k as a coupling value Λ (s _{k, 1} ) of the first demodulation symbol; A multiplier for multiplying Z _1k from the first calculator by 3 to output 3Z _1k ; A first selector receiving an inversion value of the 3Z _1k and the 3Z _1k from the multiplier and selecting and outputting one of the inputs according to the most significant bit of the quadrature component Y _k ; A second selector which receives an output of the first selector and a value of "0", selects and outputs one of the inputs according to the most significant bit of Z _1k ; A third calculator for adding the output of the second selector to the output of the bit shifter; And the third selector to the second input receives the inverse of the Z and the Z _{2k 2k} from the second converter, and outputs the selected one of said input according to the MSB of the Z _1k, A fourth selector which receives an output of the third selector and a value of "0", selects and outputs one of the inputs according to the most significant bit of Z _2k ; A fourth calculator for adding the output of the fourth selector to Z _1k from the first calculator and outputting the output of the fourth selector as a coupling value Λ (s _{k, 2} ) of a third symbol; And a fifth selector for selecting and outputting one of said input according to the second input receives the inverse of the Z and the Z _{2k 2k} from the second calculator, MSB of the Y _k, A sixth selector which receives an output of the fifth selector and a value of "0", selects and outputs one of the inputs according to the most significant bit of Z _2k ; And a fifth calculator for adding the output of the sixth selector to the output of the third calculator and outputting the fifth calculator as a coupling value Λ (s _{k, 4} ) of the fifth symbol. The method of claim 7, wherein the second ductility value determination unit, A bit shifter for shifting the in-phase component X _k by 0 bits, 1 bit, or 2 bits according to the value of S; A first calculator for calculating the Z ' _1k with the in-phase component (X _k ), the minimum distances 2a, and S; 2 for calculating a wherein Z has the _1k and the minimum distance 2a, _2k wherein Z from the first converter, and outputting the Z _'2k in two soft value _{(Λ (s k, 1)} ) of a second demodulated symbol With calculator, A multiplier for outputting 3Z _1k by multiplying Z ' _1k from the first calculator by 3; A first selector receiving an inverted value of the 3Z _1k and the 3Z _1k from the multiplier and selecting and outputting one of the inputs according to the most significant bit of the in-phase component (X _k ); A second selector which receives an output of the first selector and a value of "0", selects and outputs one of the inputs according to the most significant bit of Z '_1k; A third calculator for adding the output of the second selector to the output of the bit shifter; And the third selector to the second input receives the inverse of Z _'2k and the Z' _2k from the second converter, and outputs the selected one of said input according to the MSB of the Z _'1k, A fourth selector which receives an output of the third selector and a value of "0", selects and outputs one of the inputs according to the most significant bit of Z '_2k; A fourth calculator for adding the output of the fourth selector to the Z ' _1k from the first calculator and outputting the output of the fourth selector as a coupling value Λ (s _{k, 3} ) of a fourth symbol; And the fifth selector to the second input receives the inverse of Z _'2k and the Z' _2k from the second converter, and outputs the selected one of said input according to the MSB of the X _k, A sixth selector which receives an output of the fifth selector and a value of "0", selects one of the inputs according to the most significant bit of Z ' _2k , and outputs the selected one; And a fifth calculator for adding the output of the sixth selector to the output of the third calculator and outputting the result of the sixth symbol as a coupling value (Λ (s _{k, 5} )). The k-th received signal R _k (X _k , Y _k ) consisting of quadrature component Y _k and in-phase component X _k is input, and the coupling values for decoding of the received signal R _k (X _k , Y _k ) are input. In the 64-ary quadrature amplitude modulation (64QAM) demodulation method to determine, Of the six demodulation symbols, using the minimum distance (2a) between the signal points in the 64QAM constellation, the signal point closest to the origin in the 64QAM constellation, the distance (α) between each axis, and the quadrature component Y _k . Determining the coupling values (Λ (S _k , ₄ ), Λ (S _k , ₂ ), Λ (S _k , ₀ )) of the three demodulation symbols related to the quadrature component Y _k using the following equation; , By using the minimum distance 2a and the distance α and the in-phase component X _k , the coupling values Λ (S _k of three demodulation symbols related to the in-phase component X _k among the six demodulation symbols , ₅ ), Λ (S _k , ₃ ), Λ (S _k , ₁ )) using the following equation.

Here, "2a" is the minimum distance between signal points in the 16QAM constellation, and "S" represents a multiple of the a for the distance to each axis of the signal point closest to the origin in the 16QAM constellation ( α = Sa). The method of claim 10, wherein the determining of the ductility values associated with the quadrature component Y _k comprises: Translating the quadrature component Y _k by 0 bits, 1 bit, or 2 bits according to the value of S; Calculating Z _1k with the quadrature signal Y _k and the minimum distances 2a and S; Calculating the Z _2k with the Z _1k and the minimum distance 2a and outputting the Z _2k as a coupling value Λ (s _{k, 0} ) of the first demodulation symbol; Outputting 3Z _1k by multiplying Z _1k by 3; Selecting one of the inversion values of the 3Z _1k and the 3Z _1k according to the most significant bit of the quadrature component Y _k and outputting the first digital value as a first digital value; Selecting one of a signal selected according to the most significant bit of the quadrature component Y _k and a value of "0" according to the most significant bit of Z _1k and outputting it as a second digital value; Outputting an intermediate value by adding the second digital value selected according to the most significant bit of Z _1k to the bit shifted quadrature component; The process of the output as a third digital value by selecting one of the inverse of the Z and the Z _{2k 2k} according to the MSB of the Z _1k and, Selecting one of the third digital value and the “0” value according to the most significant bit of Z _2k and outputting the fourth digital value as a fourth digital value; Adding the fourth digital value to the Z _1k and outputting the combined value Λ (s _{k, 2} ) of a third symbol; The process of the output as a fifth digital value by selecting one of the inverse of the Z and the Z _{2k 2k} according to the MSB of the Y _k and, Selecting one of the fifth digital value and the zero value according to the most significant bit of Z _2k and outputting the sixth digital value as a sixth digital value; And adding the sixth digital value to the intermediate value and outputting the result as a soft value (Λ (s _{k, 4} )) of a fifth symbol. The method of claim 10, wherein the determining of ductility values related to the in-phase component X _k comprises: Translating the in-phase component X _k by 0 bits, 1 bit, or 2 bits according to the value of S; Calculating Z ′ _1k using the in-phase component (X _k ), the minimum distance 2a, and S; Calculating the Z ' _2k using the Z' _1k and the minimum distance 2a and outputting the Z ' _2k as a coupling value Λ (s _{k, 1} ) of a second demodulation symbol; Outputting 3Z ' _1k by multiplying Z' _1k by 3; Selecting one of the inverted values of the 3Z ' _1k and the 3Z' _1k according to the most significant bit of the in-phase component (X _k ) and outputting the first digital value as the first digital value; Selecting one of a signal selected according to the most significant bit of the in-phase component (X _k ) and a value of "0" according to the most significant bit of Z ' _1k and outputting it as a second digital value; Adding the second digital value selected according to the most significant bit of Z ' _1k to the bit shifted quadrature component and outputting an intermediate value; The process of the output as a third digital value by selecting one of the _2k and the Z 'inverse of _2k' wherein Z in accordance with the most significant bit of _1k 'wherein Z and, Selecting one of the third digital value and the “0” value according to the most significant bit of Z ′ _2k and outputting the fourth digital value as a fourth digital value; Adding the fourth digital value to the Z ′ _1k and outputting the fourth digital value as a coupling value Λ (s _{k, 3} ) of a fourth symbol; The process of the output as a fifth digital value by selecting one of the Z _'2k and the Z' inverse of _2k according to the MSB of the X _k and, Selecting one of the fifth digital value and the “0” value according to the most significant bit of Z ′ _2k and outputting the sixth digital value as a sixth digital value; And adding the sixth digital value to the intermediate value and outputting the sixth symbol as a coupling value (Λ (s _{k, 5} )) of the sixth symbol. An input signal R _k (X _k , Y _k ) consisting of a _kth quadrature component Y _k and an in-phase component X _k is input, and soft values for decoding of the input signal R _k (X _k , Y _k ) are obtained. In an integrated demodulator of quadrature phase shift keying (QPSK), 16-ary quadrature amplitude modulation (16QAM) and 64QAM, Receiving the minimum distance (2a) between signal points in 16QAM and 64QAM constellations, the signal point closest to the origin in the 16QAM and 64QAM constellations, the distance between each axis (α = Sa), and the quadrature component Y _k , A first softness value determination unit for determining softness values of demodulation symbols related to the quadrature component Y _k among demodulation symbols; A second softness value determination unit configured to receive the minimum distance 2a, the distance α, and the in-phase component X _k and determine the soft values of demodulation symbols related to the in-phase component X _k among the demodulation symbols; Characterized by including Here, the first soft value determining unit or the second soft value determining unit, 0 bits of the input signal component that is the quadrature component Y _k or the in-phase component X _k according to the value of S that is a multiple of the distance of each axis of the signal point closest to the origin in the 16QAM constellation. A bit shifter that shifts by one or two bits, A first calculator for calculating Z _1k by subtracting (S + 1) a from the absolute value of the input signal component; A multiplier for multiplying Z _1k from the first calculator by 3 to output 3Z _1k ; A seventh selector for selecting and outputting one of the Z _1k and the 3Z _1k according to a modulation mode signal MS representing one of QPSK, 16QAM, and 64QAM; A first selector configured to receive an inverted value of an output of the seventh selector and an output of the seventh selector, and select one of the inputs according to the most significant bit of the input signal component and output the selected one; A second selector which receives an output of the first selector and a value of "0", selects and outputs one of the inputs according to the most significant bit of Z _1k ; A third calculator for adding the output of the second selector to the output of the bit shifter; A second calculator that calculates Z _2k by subtracting 2a from the absolute value of Z _1k from the first calculator; A soft value of a second demodulation symbol associated with the input signal component by receiving one of the inputs Z _1k from the first calculator and the Z _2k from the second calculator and selecting one of the inputs according to the modulation mode signal An eighth selector for outputting A third selector configured to receive an inverted value of an output of the eighth selector and an output of the eighth selector, and select one of the inputs according to the most significant bit of Z _1k and output the selected one; A fourth selector which receives an output of the third selector and a value of "0", selects and outputs one of the inputs according to the most significant bit of Z _2k ; A fourth calculator for adding the output of the fourth selector to the Z _1k from the first calculator and outputting it as a soft value of a third symbol related to the input signal component; And a fifth selector for selecting and outputting one of said input in accordance with the first input receives the inverse of the Z and the Z _{2k 2k} from the second converter, the MSB of the input signal components, A sixth selector which receives an output of the fifth selector and a value of "0", selects and outputs one of the inputs according to the most significant bit of Z _2k ; A fifth calculator for adding the output of the sixth selector to the output of the third calculator and outputting the output; A fifth calculator configured to receive the input signal component and the output of the fifth calculator and to select one of the inputs according to the modulation mode signal and output the first demodulation symbol related to the input signal component as a coupling value of the first demodulation symbol; Demodulation device characterized in that.

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