OTSM-based communication method and communication system, and computing device for performing same

Abstract

Disclosed are an OTSM-based communication method and communication system, and a computing device for performing same. The disclosed communication method according to an embodiment is an OTSM-based communication method, and comprises the steps of: generating a plurality of candidate matrices in a delay-time domain by multiplying row-unit data in a delay-sequency domain by a plurality of preset scrambled WHT (S-WHT) matrices, or generating a plurality of candidate matrices in the delay-time domain by scrambling the row-unit data in the delay-sequency domain by using a plurality of preset scrambled vectors and then multiplying same by WHT; and generating a data matrix in the delay-time domain on the basis of the plurality of candidate matrices.

Description

OSTM-based communication method and communication system and computing device for performing the same

[0001] Embodiments of the present invention relate to OTSM (Orthogonal Time Sequency Multiplexing)-based communication technology.

[0002] 5G communication networks and future 6G communication networks require stability for high-speed mobility in application fields such as communication with high-speed moving objects like high-speed trains, aircraft, and drones, and communication between autonomous vehicles (V2X). Accordingly, two-dimensional modulation techniques such as Orthogonal Time Frequency Space (OTFS) and Orthogonal Time Sequency Multiplexing (OTSM), which utilize diversity in the time-frequency domain to enhance signal robustness, have been proposed.

[0003] However, these modulation techniques face a high Peak-to-Average Power Ratio (PAPR), which is a major factor in reducing the efficiency of power amplifiers and increasing signal distortion and energy consumption. Since existing techniques to lower PAPR have the problem of offsetting signal diversity, there is a need for a method that can maximize signal diversity while maintaining a low PAPR.

[0004] An embodiment of the present invention is intended to provide an OSTM-based communication method and communication system capable of implementing a low PAPR, and a computing device for performing the same.

[0005] A communication method according to one disclosed embodiment is an Orthogonal Time Sequency Multiplexing (OTSM) based communication method performed on a computing device having one or more processors and a memory storing one or more programs executed by said one or more processors, comprising the steps of: generating a plurality of candidate matrices in a delay-time domain by multiplying row-unit data in a delay-sequence domain by a plurality of pre-set scrambled WHT (Scrambled Walsh Hadamard Transform: S-WHT) matrices, or generating a plurality of candidate matrices in a delay-time domain by scrambling row-unit data in the delay-sequence domain using a plurality of pre-set scramble vectors and then multiplying by WHT; and generating a data matrix in a delay-time domain based on said plurality of candidate matrices.

[0006] The above scrambled WHT (S-WHT) matrix is ​​generated by multiplying the scrambled diagonal matrix by a WHT matrix generated according to the column size of the delay-sequence region, and the scrambled diagonal matrix may be a matrix obtained by converting a scrambled vector consisting of -1 and 1 into a diagonal matrix.

[0007] The step of generating the data matrix in the delay-time domain may include: calculating the Peak-to-Average Power Ratio (PAPR) for each row of each candidate matrix; and selecting the row having the smallest PAPR value among the rows of each candidate matrix and configuring it as the corresponding row of the data matrix in the delay-time domain.

[0008] The above communication method may further include the step of embedding additional information about an S-WHT matrix or scramble vector into the data matrix of the delay-time domain such that for each row of the data matrix of the delay-time domain, the PAPR is minimized.

[0009] The above embedding step can embed the additional information for each row of the data matrix in the delay-time domain through phase rotation.

[0010] The above additional information can be embedded by the following mathematical formula.

[0011] (Mathematical formula)

[0012]

[0013] : Data matrix in the delay-time domain with embedded additional information The i-th row of

[0014] C: Number of S-WHT matrices or scramble vectors

[0015] : Data matrix Additional information coefficient for the i-th row of

[0016] : Index of the scramble vector with the smallest PAPR value for the i-th row

[0017] The above communication method further includes the step of pre-setting the plurality of scrambled WHT (S-WHT) matrices or the plurality of scrambled vectors, and the step of pre-setting the plurality of S-WHT matrices or the plurality of scrambled vectors may include the step of searching for a combination of the scrambled vectors that can minimize the Peak-to-Average Power Ratio (PAPR) for the input data.

[0018] The step of searching for a combination of the scramble vectors above can be performed only when the digital modulation method of the data is BPSK (Binary Phase Shift Keying).

[0019] A communication system according to one disclosed embodiment is an Orthogonal Time Sequency Multiplexing (OTSM) based communication system including a transmitting device and a receiving device, wherein the transmitting device generates a plurality of candidate matrices in the delay-time domain by multiplying row-unit data in the delay-sequence domain by a plurality of pre-set scrambled WHT (Scrambled Walsh Hadamard Transform: S-WHT) matrices, or generates a plurality of candidate matrices in the delay-time domain by scrambling row-unit data in the delay-sequence domain using a plurality of pre-set scramble vectors and then multiplying by WHT, and generates a data matrix in the delay-time domain based on the plurality of candidate matrices.

[0020] According to the disclosed embodiment, by applying an S-WHT matrix, it is possible to reduce the PAPR of the signal while maintaining the robustness of the OSTM against multipath fading and Doppler shift. In particular, the advantages of the OSTM in high-speed channels can be maintained without degrading performance or changing the characteristics of the OSTM signal itself.

[0021] Figure 1 is a schematic diagram showing the process of transmitting and receiving signals in OTSM (Orthogonal Time Sequency Multiplexing).

[0022] FIG. 2 is a diagram showing an OTSM communication system according to one embodiment of the present invention.

[0023] FIG. 3 is a diagram schematically illustrating the process of transmitting and receiving signals in an OTSM communication system according to one embodiment of the present invention.

[0024] FIG. 4 is a diagram illustrating, in isolation, the process of a transmitting device generating a data matrix in the delay-time domain in an OTSM communication system according to one embodiment of the present invention.

[0025] FIG. 5 is a diagram showing an algorithm for finding a combination of scramble vectors that creates the minimum PAPR in one embodiment of the present invention.

[0026] Figure 6 is a graph comparing the PAPR using an S-WHT matrix according to one embodiment of the present invention with the PAPR of a different communication method.

[0027] Figure 7 is a graph comparing the BER performance of a different communication method with that of an S-WHT matrix according to one embodiment of the present invention.

[0028] FIG. 8 is a flowchart illustrating an OSTM-based communication method according to one embodiment of the present invention.

[0029] FIG. 9 is a block diagram illustrating a computing environment including a computing device suitable for use in exemplary embodiments.

[0030] Hereinafter, specific embodiments of the present invention will be described with reference to the drawings. The following detailed description is provided to facilitate a comprehensive understanding of the methods, apparatus, and / or systems described herein. However, this is merely illustrative and the present invention is not limited thereto.

[0031] In describing the embodiments of the present invention, detailed descriptions of known technologies related to the present invention are omitted if it is determined that such detailed descriptions may unnecessarily obscure the essence of the present invention. Furthermore, the terms described below are defined in consideration of their functions within the present invention, and these may vary depending on the intentions or practices of the user or operator. Therefore, such definitions should be based on the content throughout this specification. Terms used in the detailed description are intended merely to describe the embodiments of the present invention and should not be limiting in any way. Unless explicitly stated otherwise, expressions in the singular form include the meaning of the plural form. In this description, expressions such as "include" or "comprise" are intended to refer to certain characteristics, numbers, steps, actions, elements, parts thereof, or combinations thereof, and should not be interpreted to exclude the existence or possibility of one or more other characteristics, numbers, steps, actions, elements, parts thereof, or combinations thereof other than those described.

[0032] Additionally, terms such as "first," "second," etc., may be used to describe various components, but said components should not be limited by said terms. These terms may be used for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be named the second component, and similarly, the second component may be named the first component.

[0033] In the disclosed embodiment, a new method is proposed to maximize diversity while effectively reducing the Peak-to-Average Power Ratio (PAPR) by utilizing the Walsh-Hadamard Transform (WHT) characteristics of Orthogonal Time Sequency Multiplexing (OTSM). Specifically, a low PAPR OTSM technique is proposed that lowers PAPR by selectively using a Scrambled-WHT (S-WHT) matrix and maximizes diversity while maintaining the orthogonality of WHT.

[0034] More specifically, a diagonal matrix is ​​generated to multiply each column of the WHT matrix by a value of 1 or -1, and this is multiplied by the original WHT matrix to create an S-WHT matrix. By selecting the matrix that minimizes PAPR from among the various S-WHT matrices generated in this way and performing data transformation, the PAPR of the entire system can be lowered. Since the column components of the S-WHT matrix generated in this manner still maintain orthogonality, it is possible to generate a low PAPR signal by reducing the effect of large PAPR generation during the transformation process while guaranteeing data orthogonality.

[0035] Figure 1 is a schematic diagram showing the process of transmitting and receiving signals in OTSM (Orthogonal Time Sequency Multiplexing).

[0036] Referring to Fig. 1, OTSM is a modulation scheme that places data symbols in the delay-sequence domain and then converts them to the delay-time domain using the Walsh-Hadamard Transform (WHT). The data matrix in the delay-sequence domain (DS domain) is It can be represented as follows. Here, M and N represent the number of grids on the delay axis and the sequence axis, respectively. Data matrix The matrix in the delay-time domain (DT domain) obtained by applying the Walsh-Hadamard Transform (WHT) to the sequence axis as shown in Equation 1 below It can be converted to.

[0037] (Mathematical Formula 1)

[0038]

[0039] : M×N normalized WHT matrix

[0040] And, data matrix By applying Zero Padding (ZP) as in Equation 2 below or Cyclic Prefix (CP) as in Equation 3 below It can generate.

[0041] (Mathematical Formula 2)

[0042]

[0043] (Mathematical Formula 3)

[0044]

[0045] Z: Length of Zero Padding

[0046] : M×M identity matrix

[0047] : Z×M zero matrix

[0048] Next, the data matrix The time-domain sample signal is vectorized in columns as shown in Equation 4 below. It can generate. Afterwards, the sample signal After pulse shaping, it is converted from digital to analog (DAC) and transmitted to a wireless communication channel.

[0049] (Mathematical Formula 4)

[0050]

[0051] Furthermore, the reception process undergoes the reverse of the transmission process. Since the transmission and reception processes of this OSTM are already known technology, a detailed explanation thereof will be omitted.

[0052] Meanwhile, when performing the Walsh-Hadamard transform in OTSM, the Walsh-Hadamard transform (WHT) is applied row-wise to the sequence axis of the delay-sequence region. At this time, due to WHT, the signal has a high PAPR (Peak-to-Average Power Ratio).

[0053] Accordingly, in the disclosed embodiment, to ensure that the signal has a low PAPR, a new WHT that lowers PAPR can be found and utilized by multiplying the WHT by the diagonal matrix of the binary scramble. Here, the new WHT obtained by multiplying the WHT by the diagonal matrix of the binary scramble can be referred to as the scrambled WHT (S-WHT). That is, an S-WHT that minimizes the signal's PAPR can be found and applied to the sequence axis in the delay-sequence domain.

[0054] FIG. 2 is a diagram showing an OTSM communication system according to an embodiment of the present invention, FIG. 3 is a diagram schematically showing the process of transmitting and receiving signals in an OTSM communication system according to an embodiment of the present invention, and FIG. 4 is a diagram showing the process of a transmitting device generating a data matrix in a delay-time domain in an OTSM communication system according to an embodiment of the present invention in isolation.

[0055] Referring to FIGS. 2 to 4, the OTSM communication system (100) may include a transmitting device (102) and a receiving device (104). The transmitting device (102) and the receiving device (104) are connected to each other so as to communicate through a communication network.

[0056] The transmitting device (102) can receive data bits, digitally modulate them, and then map the modulated data symbols to a delay-sequence region. The transmitting device (102) can generate multiple candidate matrices in the delay-time region by multiplying each row of data in the delay-sequence region by S-WHT.

[0057] Specifically, S-WHT matrix is a 1×N scrambled vector consisting of -1 and 1 The original WHT matrix in the matrix transformed into a diagonal matrix (hereinafter referred to as the scrambled diagonal matrix) It can be defined as multiplying by. This can be expressed by mathematical formula 5.

[0058] (Mathematical Formula 5)

[0059]

[0060] : Scrambled diagonal matrix

[0061] Here, k = 1, 2, ..., C, where C is the number of S-WHT matrices. Accordingly, multiple S-WHT matrices (i.e., C) can be generated. In one embodiment, scramble vector It can include cases where the values ​​consist only of 1s. In this case, the S-WHT matrix becomes identical to the original WHT matrix. That is, the S-WHT matrix It can also include the original WHT matrix. In this case, s1= [1, 1, 1, 1] can be used.

[0062] Meanwhile, the transmitting device (102) may generate multiple candidate matrices in the delay-time domain by multiplying row-unit data in the delay-sequence domain and multiple scramble vectors element-wise and then multiplying by WHT. That is, it may generate multiple candidate matrices in the delay-time domain by scrambling row-unit data in the delay-sequence domain using scramble vectors and then multiplying by WHT.

[0063] The transmitting device (102) is a data matrix in the delay-sequence area S-WHT matrix on row-by-row data By multiplying each one, C candidate matrices in the delay-time domain are obtained as shown in Equation 6. Each can be generated. In this case, the data matrix C candidate matrices for This will be generated.

[0064] (Mathematical Formula 6)

[0065]

[0066] The transmitting device (102) is each candidate matrix For the i-th row of, PAPR can be calculated by the following mathematical formula 7.

[0067] (Mathematical Formula 7)

[0068]

[0069] Here, i = 1, 2, ..., M, and Is It is the i-th row of, and Is It is the element corresponding to the i-th row and j-th column of.

[0070] The transmitting device (102) is each candidate matrix We can find the index k of the scramble vector that has the smallest PAPR value among the i-th rows. This can be expressed by Equation 8 below.

[0071] (Mathematical Formula 8)

[0072]

[0073] The transmitting device (102) is each candidate matrix Select the row with the smallest PAPR value among the i-th rows to obtain the data matrix in the delay-time domain. It can be composed of the i-th row. This can be expressed by the mathematical formula 9 below.

[0074] (Mathematical Formula 9)

[0075]

[0076] The transmitting device (102) is each candidate matrix For all rows, select the rows with the smallest PAPR to obtain the data matrix in the delay-time domain. It can be constructed as shown in mathematical formula 10 below.

[0077] (Mathematical Formula 10)

[0078]

[0079] The transmitting device (102) is a data matrix For each row, side information can be embedded regarding which S-WHT matrix has the smallest PAPR among the S-WHT matrices. The side information may include the number of S-WHT matrices and the index of the scramble vector that has the smallest PAPR value for each row. At this time, the transmitting device (102) can transmit by embedding the side information within the data frame without additional transmission.

[0080] The transmitting device (102) is a data matrix Additional information can be embedded for each row of through phase rotation. This can be expressed by Equation 11 below.

[0081] (Mathematical Formula 11)

[0082]

[0083] : Data matrix with embedded additional information The i-th row of

[0084] C : Number of S-WHT matrices

[0085] : Additional information coefficient for the i-th row of

[0086] : Index of the scramble vector with the smallest PAPR value for the i-th row

[0087] This is the scrambled vector with the smallest PAPR value for the i-th row This utilizes the constellation invariant property that it possesses because it is a binary vector consisting of 1 and -1. Here, the transmitting device (102) distinguishes C S-WHTs. By dividing it into C, different phase rotations can be applied according to each S-WHT matrix. That is, different constellations are formed according to the S-WHT matrix based on the degree of phase rotation, and the receiving device (104) detects this and can determine the S-WHT matrix used in the transmitting device (102) (i.e., the S-WHT matrix that causes PAPR to have a minimum value).

[0088] The transmitting device (102) is a data matrix in which additional information is embedded. After applying Zero Padding (ZP) or Cyclic Prefix (CP), the signal s(t) in the time domain can be generated by vectorizing it in columns. The transmitting device (102) can transmit the signal s(t) to the receiving device (104).

[0089] The receiving device (104) can receive a signal s(t) transmitted by the transmitting device (102). Based on the received signal s(t), the receiving device (104) has a data matrix in the delay-time domain. It can generate a data matrix in the delay-time domain through de-vectorization and zero padding or cyclic prefix removal processes for the received signal s(t).

[0090] The receiving device (104) is a data matrix in the delay-time domain Data matrix of the delayed-sequence region via WHT for It can be obtained. The receiving device (104) is a data matrix in the delay-sequence region. Based on the additional information embedded in each row, the S-WHT matrix used in the transmitting device (102) (i.e., the S-WHT matrix that causes PAPR to have a minimum value) can be detected. That is, the receiving device (104) has a data matrix Based on the additional information coefficient of each row (i.e., estimate the index of the scramble vector with the smallest PAPR value for the i-th row) ) can.

[0091] Specifically, since the additional information is embedded through phase rotation in the transmitting device (102), the receiving device (104) is a data matrix The additional information coefficient in each row of It can detect. Here, There are two ways to detect it. One is to use the Maximum Likelihood method, and the other is to use a minimum distance-based method.

[0092] First, I will explain the Maximum Likelihood method.

[0093] A digital modulated symbol that has been phase-rotated by that amount is It is the same as. The receiving device (104) is a data matrix and digital modulation symbol set The Euclidean distance between them can be calculated as shown in Equation 12 below.

[0094] (Mathematical Formula 12)

[0095]

[0096] : Data matrix The element of the i-th row and n-th column

[0097] : Phase-rotated digital modulation symbol corresponding to the scramble vector index k

[0098] Here, the symbol Is Satisfies.

[0099] The receiving device (104) is a data matrix and digital modulation symbol set Digital modulation symbols considering the Euclidean distance and noise power between The likelihood function for can be calculated as shown in Equation 13 below.

[0100] (Mathematical Formula 13)

[0101]

[0102] Here, is Additive White Gaussian Noise (AWGN).

[0103] The receiving device (104) and digital modulation symbol set The Euclidean distance-based likelihood function between them can be calculated as shown in Equation 14 below. That is, each digital modulation symbol calculated through Equation 14 The likelihood function for can be summed.

[0104] (Mathematical Formula 14)

[0105]

[0106] Here, Is and digital modulation symbol set It is a distance-based probability between, representing the probability of a signal occurring in a set of digital modulated symbols based on the calculated distance. This The product probability of all columns n for can be calculated as shown in Equation 15 below. That is, For all columns n of the i-th row of, the product probability can be calculated as in Equation 15 by multiplying the likelihood function calculated in Equation 14.

[0107] (Mathematical Formula 15)

[0108]

[0109] Here, the receiving device (104) can estimate the index of the scramble vector of the i-th row by selecting a k value that has the maximum likelihood as in Equation 16 below.

[0110] (Mathematical Formula 16)

[0111]

[0112] The receiving device (104) is a data matrix Index of the estimated scramble vector for each row The final delay-sequence data matrix can be calculated as shown in Equation 17 below.

[0113] (Mathematical Formula 17)

[0114]

[0115] Next, we will explain the minimum distance-based method. The minimum distance-based method is a method that has lower complexity than the maximum likelihood method.

[0116] The receiving device (104) is a data matrix The minimum distance between the elements of the i-th row and n-th column of and the phase-rotated digital modulated symbol can be calculated. This can be expressed as Equation 18.

[0117] (Mathematical Formula 18)

[0118]

[0119] Next, the receiving device (104) is a data matrix For all column components of the i-th row, the minimum distance calculated above can be summed to calculate the total distance for the index k of the scramble vector as shown in Equation 19 below.

[0120] (Mathematical Formula 19)

[0121]

[0122] Next, the receiving device (104) can estimate the index of the scramble vector of the i-th row as in Equation 20 by selecting the k value with the smallest total distance for the index k of the scramble vector.

[0123] (Mathematical Formula 20)

[0124]

[0125] The receiving device (104) is a data matrix Index of the estimated scramble vector for each row The final delay-sequence data matrix can be calculated as shown in Equation 17.

[0126] Meanwhile, before the transmitting device (102) communicates with the receiving device (104), it has an S-WHT set capable of minimizing PAPR (i.e., ) can be set. In other words, since actual data is generated randomly, a fixed S-WHT set that can minimize PAPR for all data (i.e., ) must be explored in advance. Here, since WHT is a pre-set value, searching for a fixed S-WHT set that can minimize PAPR for all data means scramble vector It becomes a problem of exploring.

[0127] In one embodiment, the transmitting device (102) is a scramble vector When searching for, the range of the data's digital modulation method can be limited to BPSK (Binary Phase Shift Keying). For example, if the digital modulation method is QPSK (i.e., 4-QAM), the data signal vector is It is expressed as and each component is It satisfies. In this case, if a WHT transform is performed on the data signal vector d, and, the i-th component of y y i It can be expressed as shown in mathematical formula 21 below.

[0128] (Mathematical Formula 21)

[0129]

[0130] Here, since d, which maximizes the PAPR value of y, is a BPSK multiplied by a constant complex constant, the digital modulation method can be limited to BPSK when searching for a scramble vector that lowers the PAPR. Therefore, the transmitting device (102) [can use] all BPSK data combinations (i.e., 2 N For ), combinations of scramble vectors that minimize PAPR can be explored.

[0131] The transmitting device (102) has an S-WHT matrix of all combinations of scrambled vectors for each BPSK data. Candidate matrix by multiplying Each can be generated. Here, the transmitting device (102) is a candidate matrix For each i-th row, a maximum peak can be extracted. The transmitting device (102) can search for a scramble vector that generates the smallest peak among the extracted maximum peaks. The transmitting device (102) can perform this operation for all k-th rows.

[0132] In this way, the transmitting device (102) can extract scramble vectors that create the minimum PAPR for each BPSK data and create a combination of scramble vectors to generate S-WHT. For example, a method to find a combination of s1 and s2 that creates the minimum PAPR when C=2 can be represented as Algorithm 1 shown in FIG. 5.

[0133] Figure 6 is a graph comparing the PAPR of a different communication method with the PAPR of an S-WHT matrix according to an embodiment of the present invention. Here, the PAPR is shown when the data is QPSK, M=129, and N=16. Referring to Figure 6, it can be seen that the method according to the embodiment of the present invention (proposed scramble method) shows a lower PAPR than other communication methods (conventional OTSM, conventional OTFS, SLM, DFT-s-OTFS).

[0134] Figure 7 is a graph comparing the BER performance of a different communication method with that of an S-WHT matrix according to an embodiment of the present invention. Here, the Bit Error Rate (BER) performance according to the Signal to Noise Ratio (SNR) is shown when the data is QPSK, M=129, and N=16. Referring to Figure 7, it can be seen that the BER performance of the method according to the embodiment of the present invention (proposed scramble method) is almost identical to that of other communication methods (conventional OTSM, conventional OTFS, SLM, DFT-s-OTFS).

[0135] According to the embodiment disclosed as described above, by applying an S-WHT matrix, it is possible to reduce the PAPR of the signal while maintaining the robustness of the OSTM against multipath fading and Doppler shift. In particular, the advantages of the OSTM in high-speed channels can be maintained without degrading performance or changing the characteristics of the OSTM signal itself.

[0136] FIG. 8 is a flowchart illustrating an OSTM-based communication method according to an embodiment of the present invention. Although the method is described in the illustrated flowchart in a plurality of steps, at least some of the steps may be performed in a different order, combined with other steps, omitted, divided into detailed steps, or performed with one or more steps not illustrated added.

[0137] Referring to FIG. 8, the transmitting device (102) can set a combination of scramble vectors to generate S-WHT by extracting scramble vectors that create a minimum PAPR for each BPSK data (S 101).

[0138] Next, the transmitting device (102) can generate a plurality of candidate matrices in the delay-time domain by multiplying the row-unit data in the delay-sequence domain by an S-WHT matrix according to the combination of the set scramble vectors (S 103).

[0139] Next, the transmitting device (102) calculates the Peak-to-Average Power Ratio (PAPR) for each row of each candidate matrix (S 105), and selects the row with the smallest PAPR value among the rows of each candidate matrix to form the corresponding row of the data matrix in the delay-time domain (S 107).

[0140] Next, the transmitting device (102) can embed additional information for an S-WHT matrix into the data matrix in the delay-time domain such that for each row of the data matrix in the delay-time domain, the PAPR is minimized (S 109).

[0141] Next, the transmitting device (102) can apply Zero Padding (ZP) or Cyclic Prefix (CP) to a data matrix with additional information embedded therein, then vectorize it column by column to generate a time domain signal s(t) and transmit it to the receiving device (104) (S 111).

[0142] FIG. 9 is a block diagram illustrating a computing environment (10) including a computing device suitable for use in exemplary embodiments. In the illustrated embodiments, each component may have different functions and capabilities in addition to those described below, and may include additional components in addition to those described below.

[0143] The illustrated computing environment (10) includes a computing device (12). In one embodiment, the computing device (12) may be a communication device for OSTM communication. The computing device (12) may be a communication device for causing the OSTM transmission signal to have a low PAPR signal overall. That is, the computing device (12) may be a transmitting device (102). Additionally, the computing device (12) may be a receiving device (104).

[0144] The computing device (12) includes at least one processor (14), a computer-readable storage medium (16), and a communication bus (18). The processor (14) can cause the computing device (12) to operate according to the exemplary embodiment described above. For example, the processor (14) can execute one or more programs stored in the computer-readable storage medium (16). The one or more programs may include one or more computer-executable instructions, and the computer-executable instructions may be configured to cause the computing device (12) to perform operations according to the exemplary embodiment when executed by the processor (14).

[0145] A computer-readable storage medium (16) is configured to store computer-executable instructions or program code, program data and / or other suitable forms of information. A program (20) stored in the computer-readable storage medium (16) includes a set of instructions executable by a processor (14). In one embodiment, the computer-readable storage medium (16) may be memory (volatile memory such as random access memory, non-volatile memory, or a suitable combination thereof), one or more magnetic disk storage devices, optical disk storage devices, flash memory devices, or other forms of storage media that are accessed by a computing device (12) and capable of storing desired information, or a suitable combination thereof.

[0146] The communication bus (18) interconnects various other components of the computing device (12), including the processor (14) and the computer-readable storage medium (16).

[0147] The computing device (12) may also include one or more input / output interfaces (22) and one or more network communication interfaces (26) that provide interfaces for one or more input / output devices (24). The input / output interfaces (22) and network communication interfaces (26) are connected to a communication bus (18). The input / output devices (24) may be connected to other components of the computing device (12) through the input / output interfaces (22). An exemplary input / output device (24) may include an input device such as a pointing device (such as a mouse or trackpad), a keyboard, a touch input device (such as a touchpad or touchscreen), a voice or sound input device, various types of sensor devices and / or imaging devices, and / or an output device such as a display device, a printer, a speaker and / or a network card. An exemplary input / output device (24) may be included inside the computing device (12) as a component constituting the computing device (12), or it may be connected to the computing device (12) as a separate device distinct from the computing device (12).

[0148] Although representative embodiments of the present invention have been described in detail above, those skilled in the art will understand that various modifications can be made to the above-described embodiments without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined by the claims set forth below as well as equivalents thereof.

Claims

1. One or more processors, and An OTSM (Orthogonal Time Sequency Multiplexing) based communication method performed on a computing device having a memory that stores one or more programs executed by the above-mentioned one or more processors, A step of generating multiple candidate matrices in the delay-time domain by multiplying row-unit data in the delay-sequence domain by a plurality of pre-set Scrambled Walsh Hadamard Transform (S-WHT) matrices, or generating multiple candidate matrices in the delay-time domain by scrambling row-unit data in the delay-sequence domain using a plurality of pre-set scramble vectors and then multiplying by WHT; and A communication method comprising the step of generating a delay-time domain data matrix based on the plurality of candidate matrices above.

2. In Claim 1, The above scrambled WHT (S-WHT) matrix is, It is generated by multiplying the scrambled diagonal matrix by the WHT matrix generated according to the column size of the above-mentioned delay-sequence region, and A communication method in which the above scrambled diagonal matrix is ​​a matrix obtained by converting a scrambled vector consisting of -1 and 1 into a diagonal matrix.

3. In Claim 2, The step of generating the data matrix in the above-mentioned delay-time domain is, A step of calculating PAPR (Peak-to-Average Power Ratio) for each row of each of the above candidate matrices; and A communication method comprising the step of selecting the row having the smallest PAPR value among each row of each candidate matrix and configuring it as the corresponding row of the data matrix of the delay-time domain.

4. In Claim 3, The above communication method is, A communication method further comprising the step of embedding additional information about an S-WHT matrix or scramble vector into a data matrix in a delay-time domain such that for each row of the data matrix in the delay-time domain, the PAPR is minimized.

5. In Claim 4, The above embedding step is, A communication method that embeds the additional information through phase rotation for each row of the data matrix in the above delay-time domain.

6. In Claim 5, The above additional information is a communication method embedded by the following mathematical formula. (Mathematical formula) : Data matrix in the delay-time domain with embedded additional information The i-th row of C: Number of S-WHT matrices or scramble vectors : Data matrix Additional information coefficient for the i-th row of : Index of the scramble vector with the smallest PAPR value for the i-th row 7. In Claim 2, The above communication method is, The method further includes the step of pre-setting the plurality of scrambled WHT (S-WHT) matrices or the plurality of scrambled vectors. The step of pre-setting the plurality of S-WHT matrices or the plurality of scramble vectors is A communication method comprising the step of searching for a combination of scramble vectors that can minimize the Peak-to-Average Power Ratio (PAPR) for input data.

8. In Claim 7, The step of searching for a combination of the above scrambled vectors is, A communication method performed by limiting the digital modulation method of the above data to BPSK (Binary Phase Shift Keying).

9. An OTSM (Orthogonal Time Sequency Multiplexing) based communication system including a transmitting device and a receiving device, The above-mentioned transmitting device is, A communication system that generates multiple candidate matrices in a delay-time domain by multiplying row-unit data in a delay-sequence domain by a plurality of pre-set scrambled WHT (Scrambled Walsh Hadamard Transform: S-WHT) matrices, or generates multiple candidate matrices in a delay-time domain by scrambling row-unit data in the delay-sequence domain using a plurality of pre-set scramble vectors and then multiplying by WHT, and generates a data matrix in the delay-time domain based on the plurality of candidate matrices.

10. In Claim 9, The above scrambled WHT (S-WHT) matrix is, It is generated by multiplying the scrambled diagonal matrix by the WHT matrix generated according to the column size of the above-mentioned delay-sequence region, and The above scrambled diagonal matrix is ​​a matrix obtained by transforming a scrambled vector consisting of -1 and 1 into a diagonal matrix, in a communication system.

11. In Claim 10, The transmitting device embeds additional information regarding an S-WHT matrix or scramble vector that minimizes the PAPR for each row of the data matrix in the delay-time domain into the data matrix in the delay-time domain through phase rotation, and The above receiving device is, A communication system that receives a signal with the additional information embedded therein from the transmitting device, calculates a data matrix of a delay-sequence region based on the received signal, and detects an S-WHT matrix used by the transmitting device based on the additional information embedded in each row of the data matrix of the delay-sequence region.

12. In Claim 11, The above receiving device is, A communication system that estimates the index of a scramble vector such that the PAPR for a corresponding row has the smallest value based on the Euclidean distance between the data matrix of the above-mentioned delay-sequence region and the phase-rotated digital modulation symbol corresponding to the index of the above-mentioned scramble vector.

13. In Claim 12, The above receiving device is, A communication system that calculates the minimum distance between the elements of each row and each column of the data matrix of the delay-sequence region and the phase-rotated digital modulation symbol, calculates the total distance for each index of the scramble vector by summing the calculated minimum distances for all column components of a specific row of the data matrix of the delay-sequence region, and estimates the index of the scramble vector with the smallest total distance as the index of the scramble vector that has the smallest PAPR.

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