KR102024307B1 - Apparatus for transmitting and receiving of sensor system using multi-level Hadamard matrix and method for transmitting and receiving method thereof - Google Patents

Abstract

The present invention relates to a transmission and reception apparatus of a sensor system using a multilevel Hadamard matrix, and a transmission method and a reception method. The present invention relates to a transmission method performed by a transmission apparatus of a sensor system. Dividing a plurality of consecutive rows or columns into at least one group, and calculating each column sum or row sum within the divided group, and using the calculated column sum or row sum, a second multilevel. Generating a Hadamard matrix, and generating a transmission signal by encoding an original signal based on the generated second multilevel Hadamard matrix.

Description

Apparatus for transmitting and receiving of sensor system using multi-level Hadamard matrix and method for transmitting and receiving method

The present invention relates to a sensor system, and more particularly, to a transmitting device and a receiving device of a sensor system using a multilevel Hadamard matrix, and a transmission method and a receiving method thereof.

The sensor system has traditionally applied multi-channel simultaneous driving and sensor methods to improve the signal-to-noise ratio (SNR) of the received signal or to obtain the spatial configuration information of the object more precisely. I have been.

In these sensor systems, capacitive multi-touch sensors have recently been applied to display panels and related user interfaces so that they can recognize multi-touch and provide a variety of user experiences. It is utilized. In the conventional sensing method of the capacitive touch panel, the AC type signal for estimating the capacitance component is time-divided and driven for each channel, and the receiving end takes a method of sensing the same. However, with the demand for cost savings and thinness, the noise effect has gradually increased with the application of in-cell technology, which integrates touch sensor electrodes on display substrates. There is a search for a technology that can obtain a high SNR compared to the time division method. As simultaneous driving and sensing schemes are preferred to acquire more capacitance signals within the same time, research on orthogonal codes to support them has begun.

1 is a diagram illustrating a comparison example of sequential time division driving and simultaneous driving of a general capacitive touch sensor.

As shown in FIG. 1, a typical capacitive touch sensor includes a touch panel 10 to which a transmitter and a receiver are connected. The capacitive touch sensor may be driven according to the sequential time division driving method shown in FIG. 1A or the simultaneous driving method shown in FIG. 1B. In the sequential time division driving method, when a plurality of channels 11 are connected to a sensor system for a touch sensor, the physical quantity of each channel is sensed as time-multiplexed. In contrast, the simultaneous driving method can obtain a high signal-to-noise ratio at the same output time when a signal is sensed using an orthogonal code for individual channels for the plurality of channels 12.

On the other hand, there is a case of the simultaneous driving ultrasonic sensor applied orthogonal Golay code (orthogonal Golay code). Due to the inherent nature of the complementary set of sequences (CSS) code, the auto-correlation of each channel is excellent.

Korean Unexamined Patent Publication No. 10-2014-0007469 (published Jan. 17, 2014)

In the conventional simultaneous driving method, when the delay time and the signal gain are different for each channel, orthogonality of the received signal is reduced, making it difficult to acquire a signal having an accurate physical quantity. In addition, a problem of deterioration of orthogonality between channels due to inherent delay / gain of a CSS code still occurs. In addition, in a sensor system to which a multi-user environment is applied, such as a lidar, a radar, and a visible light communication system, the quality of a received signal may be degraded according to the superposition characteristics of stimulus signals between users, which is inevitable for measurement physical quantity and situation recognition judgment. Error appears.

To this end, embodiments of the present invention can encode and transmit a transmission signal using a multilevel Hadamard matrix, decode the received signal received from the sensing object to effectively obtain the physical quantity of the sensing object of the sensor system, An apparatus for transmitting and receiving a sensor system using a multilevel Hadamard matrix, which is robust against interference between multiple channels of a system and can be easily applied to signal synchronization, and a transmission method and a reception method.

Embodiments of the present invention utilize a perfect orthogonal code and a decoding technique that are robust to variations in delay and channel gain, which are different between channels in a multi-channel sensor system but can be preliminarily limited as a specification. And a transmission and reception apparatus of a sensor system using a multilevel Hadamard matrix, and a transmission method and a reception method, which can be applied to a general active sensor system equipped with a receiver.

In addition, embodiments of the present invention to provide a transmission and reception apparatus of a sensor system using a multilevel Hadamard matrix, a transmission method and a reception method that can reduce the stimulus signal interference between channels that can occur in a multi-user sensor system. do.

According to an embodiment of the present invention, in a transmission method performed by a transmitting device of a sensor system, a plurality of consecutive rows or columns of a first multilevel Hadamard matrix are grouped into at least one group, and the classification is performed. Calculating each column sum or row sum in the group; Generating a second multilevel Hadamard matrix using the calculated column sum or row sum; And generating a transmission signal by encoding an original signal based on the generated second multilevel Hadamard matrix, and a transmission method of the sensor system using the multilevel Hadamard matrix may be provided.

The transmission method may modify or simplify the second multilevel Hadamard matrix by multiplying each row or each column of the generated second multilevel Hadamard matrix by a channel gain or a scale factor. It may further comprise a step.

The transmission method includes modulating the generated transmission signal; And transmitting the modulated transmission signal on a transmission channel of a sensor system at different times.

The transmitting may include transmitting the transmission signal to a transmission channel of any one of a touch sensor system, a radar system, a lidar system, a visible light communication system, and an ultrasonic system.

The rows of the second multilevel Hadamard matrix correspond to individual channels and the columns of the second multilevel Hadamard matrix represent symbols used at different times, or the columns of the second multilevel Hadamard matrix are individual Rows of the second multilevel Hadamard matrix corresponding to a channel may represent symbols used at different times.

Each row of the generated second multilevel Hadamard matrix may consist of a sum of a plurality of rows orthogonal to each other.

According to another embodiment of the present invention, a reception method performed by a receiving apparatus of a sensor system, the method comprising: receiving a reception signal output from a sensing object; Demodulating the received received signal; Decoding the demodulated received signal using a center row or a center column located in the center of each group of the second multilevel Hadamard matrix as a decoding code based on a first multilevel Hadamard matrix; And calculating the physical quantity of the sensing object by analyzing the decoded signal, wherein the received signal is changed based on the physical quantity of the sensing object by encoding a transmission signal encoded based on the second multilevel Hadamard matrix. A reception method of a sensor system using a multilevel Hadamard matrix, which is a received signal, may be provided.

The receiving method may further include amplifying the received received signal, and the demodulating may demodulate the amplified received signal.

The receiving method may further include converting the decoded received signal into a digital signal through analog-digital conversion.

The decoding may be internalized with the received signal by using, as a driving code, a central row or a central column located in the center of each group of the second multilevel Hadamard matrix based on the first multilevel Hadamard matrix.

According to another embodiment of the present invention, the plurality of consecutive rows or columns of the first multilevel Hadamard matrix are grouped into at least one group, and the column sums or row sums within the divided groups are respectively calculated. A matrix calculator; A matrix generator configured to generate a second multilevel Hadamard matrix using the calculated column sum or row sum; And a signal generator for generating a transmission signal by encoding a transmission signal based on the generated second multilevel Hadamard matrix. The apparatus for transmitting a sensor system using the multilevel Hadamard matrix may be provided.

The matrix generator may deform or simplify the second multilevel Hadamard matrix by multiplying each row or each column of the generated second multilevel Hadamard matrix by a channel gain or a scale factor. Can be.

The transmitting device includes a modulator for modulating the encoded transmission signal; And a transmitter configured to transmit the modulated transmission signal to the transmission channel of the sensor system at different times.

The transmitter may transmit the modulated transmission signal to any one of a touch sensor system, a radar system, a lidar system, a visible light communication system, and an ultrasonic system.

The rows of the second multilevel Hadamard matrix correspond to individual channels and the columns of the second multilevel Hadamard matrix represent symbols used at different times, or the columns of the second multilevel Hadamard matrix are individual Rows of the second multilevel Hadamard matrix corresponding to a channel may represent symbols used at different times.

Each row of the generated second multilevel Hadamard matrix may consist of a sum of a plurality of rows orthogonal to each other.

According to another embodiment of the present invention, a receiver for receiving a received signal output from the sensing object; A demodulator for demodulating the received received signal; A decoder which decodes the demodulated received signal using a center row or a center column located in the center of each group of the second multilevel Hadamard matrix as a decoding code based on a first multilevel Hadamard matrix; And a calculator configured to analyze the decoded signal to calculate a physical quantity of the sensing object, wherein the received signal is changed based on the physical quantity of the sensing object by encoding a transmission signal encoded based on the second multilevel Hadamard matrix. An apparatus for receiving a sensor system using a multilevel Hadamard matrix, which is a received signal, may be provided.

The receiving device may further include an amplifier for amplifying the received received signal, and the demodulator may demodulate the amplified received signal.

The receiving device may further include a converting unit converting the decoded received signal into a digital signal through analog-digital conversion.

The decoder may be internalized with the received signal using a central row or central column located in the center of each group of the second multilevel Hadamard matrix as a driving code.

Embodiments of the present invention can encode a transmission signal using a multilevel Hadamard matrix, transmit a signal, and decode a received signal received from a sensing object to effectively obtain a physical quantity of the sensing object of the sensor system. It is robust against inter-channel interference and can be easily applied to signal synchronization.

Embodiments of the present invention utilize a perfect orthogonal code and a decoding technique that are robust to variations in delay and channel gain, which are different between channels in a multi-channel sensor system but can be preliminarily limited as a specification. And a general active sensor system in which a receiver is mounted.

In addition, embodiments of the present invention may reduce stimulus signal interference between channels that may occur in a multi-user sensor system.

Embodiments of the present invention generate a stimulating signal for a separate channel of a sensor by modifying a cyclic orthogonal code having multiple levels, but each stimulus signal has the same physical quantity in a received signal processing process even though a code delay occurs. It can be converted.

In addition, embodiments of the present invention may be used to acquire a general capacitive touch sensor signal, an ultrasonic signal, a lidar, and a radar (LiDAR and RADAR) signal in which a transmission / reception block is implemented together.

In detail, embodiments of the present invention may be applied to a capacitive touch screen and a visible light communication system regardless of a range of channel delays for a plurality of transmission channels and a plurality of reception channels. Orthogonality between the sensing signals can be maintained.

Embodiments of the present invention, when applied to a multi-channel rangefinder sensor (eg, ultrasonic sensor, radar, lidar, etc.), is advantageous for the synchronization of the detection signal at the receiver, and reduces the inter-channel interference even with a range of channel delays. You can.

1 is a diagram illustrating a comparison example of sequential time division driving and simultaneous driving of a general capacitive touch sensor.
2 is a block diagram of a sensor system using a multilevel Hadamard matrix according to an embodiment of the present invention.
3 is a diagram illustrating a basic multilevel Hadamard matrix using a cyclic matrix applied to an embodiment of the present invention.
4 illustrates a combined multilevel Hadamard matrix according to an embodiment of the present invention.
FIG. 5 is a diagram illustrating a correlation between a conventional Walsh Hadamard matrix and a combined multilevel Hadamard matrix according to an embodiment of the present invention.
6 is a diagram illustrating an example of a multilevel Hadamard modulated signal applied to a capacitive touch sensor according to an exemplary embodiment of the present invention.
7 is a flowchart illustrating a transmission method in a sensor system using a multilevel Hadamard matrix according to an embodiment of the present invention.
8 is a flowchart illustrating a receiving method in a sensor system using a multilevel Hadamard matrix according to an embodiment of the present invention.
9 is a diagram illustrating a correlation between a conventional Walsh Hadamard matrix including modulation and demodulation and a multilevel Hadamard matrix according to an embodiment of the present invention.
10 is a diagram illustrating a configuration of a capacitive sensor system using a multilevel Hadamard matrix according to an embodiment of the present invention.
11 is a diagram illustrating the configuration of a radar system using a multilevel Hadamard matrix according to an embodiment of the present invention.
12 is a diagram illustrating the configuration of a LiDAR system using a multilevel Hadamard matrix according to an embodiment of the present invention.
FIG. 13 is a diagram illustrating a configuration of a visible light communication system using a multilevel Hadamard matrix according to an embodiment of the present invention.
14 is a diagram illustrating the configuration of an ultrasound system using a multilevel Hadamard matrix according to an embodiment of the present invention.
FIG. 15 is a diagram illustrating a method of reducing an interference rate of a code by applying a multilevel Hadamard matrix according to another embodiment of the present invention.
FIG. 16 is a diagram illustrating a correlation diagram when a multilevel Hadamard matrix is modulated with a Barker-11 code according to an embodiment of the present invention. FIG.

As the inventive concept allows for various changes and numerous embodiments, particular embodiments will be illustrated in the drawings and described in detail in the written description.

However, this is not intended to limit the present invention to specific embodiments, it should be understood to include all changes, equivalents, and substitutes included in the spirit and scope of the present invention.

Terms such as first and second may be used to describe various components, but the components should not be limited by the terms. The terms are used only 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 referred to as the second component, and similarly, the second component may also be referred to as the first component. The term and / or includes a combination of a plurality of related items or any item of a plurality of related items.

When a component is referred to as being "connected" or "connected" to another component, it may be directly connected to or connected to that other component, but it may be understood that other components may be present in between. Should be. On the other hand, when a component is said to be "directly connected" or "directly connected" to another component, it should be understood that there is no other component in between.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, the terms "comprise" or "have" are intended to indicate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, and one or more other features. It is to be understood that the present invention does not exclude the possibility of the presence or the addition of numbers, steps, operations, components, components, or a combination thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art. Terms such as those defined in the commonly used dictionaries should be construed as having meanings consistent with the meanings in the context of the related art, and shall not be construed in ideal or excessively formal meanings unless expressly defined in this application. Do not.

Hereinafter, with reference to the accompanying drawings, it will be described in detail a preferred embodiment of the present invention. In the following description of the present invention, the same reference numerals are used for the same elements in the drawings and redundant descriptions of the same elements will be omitted.

2 is a block diagram of a sensor system using a multilevel Hadamard matrix according to an embodiment of the present invention.

As shown in FIG. 2, the sensor system 100 using the multilevel Hadamard matrix according to an embodiment of the present invention includes a transmitting device 110 and a receiving device 120. Here, the transmitter 110 includes a matrix calculator 111, a matrix generator 112, a signal generator 113, a modulator 114, and a transmitter 115. The receiving device 120 includes a calculator 121, a converter 122, a decoder 123, a demodulator 124, an amplifier 125, and a receiver 126. Here, functions and components unnecessary to the embodiments of the present invention among the components of the transmitter 110 and the transmitter 120 may be omitted, or some components may be integrated.

First, the transmitting device 110 transmits a transmission signal to the sensing object 101. Then, the transmission signal is converted or reflected by the physical quantity of the sensing object 101 to become a reception signal.

Thereafter, the receiving device 120 receives the received signal changed by the physical quantity of the sensing object 101.

First, a detailed configuration and operation of each component of the transmitting device 110 of the sensor system 100 shown in FIG. 1 will be described.

The matrix calculator 111 divides a plurality of consecutive rows or columns of the first multilevel Hadamard matrix into at least one group, and calculates a column sum or row sum in the divided group, respectively.

The matrix generator 112 generates a second multilevel Hadamard matrix using the column sum or row sum calculated by the matrix calculator 111. Here, the rows of the second multilevel Hadamard matrix may correspond to individual channels, and the columns of the second multilevel Hadamard matrix may represent symbols used at different times. Alternatively, the columns of the second multilevel Hadamard matrix may correspond to individual channels, and the rows of the second multilevel Hadamard matrix may represent symbols used at different times. In addition, each row of the second multilevel Hadamard matrix may consist of a sum of a plurality of rows orthogonal to each other. The matrix generator 112 transforms or simplifies the second multilevel Hadamard matrix by multiplying each row or each column of the generated second multilevel Hadamard matrix by a channel gain or a scale factor. Can be.

The signal generator 113 generates a transmission signal by encoding a transmission signal based on the second multilevel Hadamard matrix generated by the matrix generator 112.

The modulator 114 modulates the transmission signal encoded by the signal generator 113.

The transmitter 115 transmits the transmission signal modulated by the modulator 114 to the transmission channel of the sensor system 100 at different times. Here, the transmitter 115 may transmit a modulated transmission signal to any one of a touch sensor system, a radar system, a lidar system, a visible light communication system, and an ultrasonic system.

Next, a detailed configuration and operation of each component of the receiving device 120 of the sensor system shown in FIG. 2 will be described.

The receiver 126 receives the received signal output from the sensing object 101.

The amplifier 125 amplifies the received signal received by the receiver 126.

The demodulator 124 demodulates the received signal amplified by the amplifier 125. If the demodulator 124 is connected to the receiver 126 without an amplifier, the demodulator 124 may demodulate the received signal received by the receiver 126.

The demodulator 124 demodulates the received signal amplified by the amplifier 124.

The decoder 123 decodes the demodulated received signal using a center row or a center column located in the center of each group of the second multilevel Hadamard matrix as a decoding code based on the first multilevel Hadamard matrix. The decoder 123 may internalize the received signal using a center row or a center column located in the center of each group of the second multilevel Hadamard matrix as a driving code based on the first multilevel Hadamard matrix.

The converter 122 may convert the received signal decoded by the decoder 123 into a digital signal through analog-digital conversion.

The calculator 121 analyzes the signal decoded by the decoder 123 or calculates a physical quantity of the sensing object using the digital signal converted by the converter 122.

Here, the received signal is a signal in which the transmission signal encoded based on the second multilevel Hadamard matrix is received by being changed by the physical quantity of the sensing object 101.

3 is a diagram illustrating a basic multilevel Hadamard matrix using a cyclic matrix applied to an embodiment of the present invention.

The transmitter 110 according to an embodiment of the present invention generates a new orthogonal code based on an n-th order multilevel Hadamard matrix. First, a basic multilevel Hadamard matrix 310 applied to an embodiment of the present invention will be described. The basic multilevel Hadamard matrix 310 is composed of a component 311 with a diagonal component, and b component 312 except for the diagonal component. If the column sum or row sum of the basic multilevel Hadamard matrix 310 is defined as m, it is expressed as a = m (2 / n-1) and b = 2m / n. The transmitter 110 may generate a combined multilevel Hadamard code that is a cyclic matrix by using the column sum or the row sum of the basic multilevel Hadamard matrix 310. Here, the basic multilevel Hadamard matrix 310 will be referred to as a first multilevel Hadamard matrix, and the combined multilevel Hadamard matrix will be referred to as a second multilevel Hadamard matrix. Each row or column of such a multilevel Hadamard matrix is completely orthogonal to each other. It is represented by the following [Equation 1].

Here, the column sum or row sum of the Hadamard matrix is m, and a = m (2 / n-1) and b = 2m / n.

In addition, there is only one a component 311 in each row, and the continuous row consists of a cyclic shift of the previous row to the right. The Hadamard code is arranged symmetrically in both the column and row directions, but for convenience, it is abbreviated to encode only on a row basis. That is, the embodiment of the present invention is not limited to encoding only on a row basis, but may also be encoded on a column basis.

4 illustrates a combined multilevel Hadamard matrix according to an embodiment of the present invention.

As shown in (a) of FIG. 4, the transmitting apparatus 110 according to an embodiment of the present invention may include rows 1-3 and 4-6 in the basic multilevel Hadamard matrix 310 illustrated in FIG. 3. Calculate the column sum by grouping three consecutive rows, such as lines 7-9. That is, a new combined multilevel Hadamard matrix 410 is shown, which is reduced in size by one third compared to the basic multilevel Hadamard matrix 310 of FIG. 3. The size of the combined multilevel Hadamard matrix 410 is reduced by the ratio divided by the number of rows grouped together. That is, each row of the multilevel Hadamard matrix 410 of FIG. 4A consists of a sum of columns of three rows that are orthogonal.

As described above, in the exemplary embodiments of the present invention, the first multilevel Hadamard matrix 310 is divided into a group consisting of a plurality of rows, and the second multilevel Hadamard matrix 410 is generated by using the sum of columns in the group. do. In the embodiments of the present invention, the generated second multilevel Hadamard matrix 410 is used as a basic sign of the stimulus signal. Here, the stimulus signal may be referred to as a transmission signal in the sensor system 100 according to embodiments of the present invention, and is not limited to a specific signal according to the type of sensor system.

In an active sensor system according to an exemplary embodiment of the present invention, a sign of each row of the second multilevel Hadamard matrix 410 is applied to a separate channel of a sensor at different times to sense a target physical quantity. That is, the rows of the second multilevel Hadamard matrix 410 correspond to individual channels, and the columns mean signs used at different times. In contrast, the columns of the second multilevel Hadamard matrix 410 may correspond to individual channels, and the rows may mean symbols used at different times.

On the other hand, the physical quantity causes a change in the sensed code size. To easily express this, k _i in each row of FIG. It can be transformed or simplified by multiplying the channel gain 420 or the scale factor, respectively. Where i represents the index of the row and i is represented by 1 to n / 3. A signal commonly sensed in n / 3 channels is expressed by Equation 2 below.

According to an embodiment of the present invention, each row of the second multilevel Hadamard matrix 410 shown in FIG. 4 is directly used as a decoding code to decode the sensing signal in the receiving device 120 of the sensor system 100. Rather than using a central row within each group based on the first multilevel Hadamard matrix 310. For example, in the case where three rows are grouped as shown in FIG. 4, two rows, five rows, eight rows,..., Based on the first multilevel Hadamard matrix 310 of FIG. As shown below, the middle row located in the middle of each group is used as a decoding code. In order to detect k ₁ , when Equation 2 is dot product of FIG.

Therefore, the reception device 120 may convert the channel gain k ₁ by dividing the obtained decoding result by m ^{2, which} is a square of ten sums.

Since the column direction in the driving matrix refers to the time axis, the center row of each group means non-delayed decoding codes in a circular structure such as the first multilevel Hadamard matrix 310 of FIG. 3. Thus, the first of the three rows becomes the code one code earlier in time, and the third is the one code delayed code. That is, the reception device 120 may decode by using the center row of each group. However, the reception device 120 may calculate the detection signal even when the code is not exactly aligned on the time axis with the self code.

FIG. 5 is a diagram illustrating a correlation between a conventional Walsh Hadamard matrix and a combined multilevel Hadamard matrix according to an embodiment of the present invention.

In order to confirm that the embodiments of the present invention can produce a sense signal even if the sign is not exactly aligned on the time axis with the self code, FIG. 5 illustrates a general 12th Walsh-Hadamard matrix and a diagram. Correlation of the twelfth order Hadamard matrix of the second multilevel Hadamard matrix 410 of 4 is shown in comparison. The decoded code for the multilevel Hadamard matrix according to an embodiment of the present invention applied to the correlation comparison is applied to the second row of FIG. 3, k ₁ = 2.0, and the remaining channel gain is fixed at 1.0. On the correlation comparison graph, the resolution of the time delay was set to 1/5000 of one code. As a result, the sign and decoding scheme according to an embodiment of the present invention can accurately infer k ₁ even if a delay of 1 code occurs based on the code of the center row. It can be seen that interference (k ₂ to k _{n / 3} ) of sensing physical quantities of other channels other than the original channel among the plurality of channels can be theoretically minimized.

In order to maintain orthogonality with respect to a time delay of ± 2 codes based on the center code, the second multilevel Hadamard matrix according to another embodiment of the present invention may have 1 to 5 rows, 6 to 10 rows in FIG. Each group may be composed of five rows of rows and the like. It can support a total of n / 5th sense channels. In order to simultaneously increase the number of sense channels and the delay robustness, the order n of the first multilevel Hadamard matrix 310 of FIG. 3 may be increased or changed. At this time, the number of columns of the final configuration matrix may increase. Here, the number of columns represents the stimulus signal generation time and the detection time.

On the other hand, the second multi-level Hadamard matrix according to another embodiment of the present invention is 1 to 3 rows, 5 to 7 rows, 9 to 11 rows, etc., in the 1 to 3 rows, 6-8 rows, 10- Each group may be composed of three rows consisting of 12 rows and the like. That is, each group may be configured with the remaining rows except for the rows (eg, 4 rows, 4-5 rows, etc.) excluded from the first multilevel Hadamard matrix 310.

6 is a diagram illustrating an example of a multilevel Hadamard modulated signal applied to a capacitive touch sensor according to an exemplary embodiment of the present invention.

The sensor system 100 according to the embodiments of the present invention performs a modulation and demodulation process in addition to the radar system using the RF signal in order to actually implement.

In one example, the capacitive sensor includes a touch panel 604 and encodes a signal using a multilevel Hadamard code 601. Here, an example of a Hadamard code signal in which the multilevel Hadamard code 601 has n = 9, m = 4, and ± 1 code delay is shown in FIG. The capacitive sensor gives a multilevel Hadamard code 601 an alternating current (AC) signal 602 to produce a multi-level TX signal 603. The generated multilevel transmission signal 603 passes through the target capacitance. In the touch panel 604, a physically formed capacitance is formed in the channel. Looking at the amplifier output, when there is no user touch on the capacitive sensor, the received signal 605 has a signal value of a predetermined magnitude. On the other hand, when there is a user touch on the capacitive sensor, the received signal 606 has a signal value changed in time according to the physical quantity of the user touch. For example, the signal value of the received signal 606 may be represented as [0.89, 0.89, 0.89, 0.89, -3.11, 0.89, 0.89, 0.89, 0.89]. Here, one code sequence may consist of nine codes (1 code sequences = 9 codes). One code may consist of 10 chips (1 code = 10 chips).

For example, in order to add orthogonality to the optical signal, the visible light signal VLC and the lidar signal LiDAR are modulated and transmitted by AC or Manchester code to a given code.

7 is a flowchart illustrating a transmission method in a sensor system using a multilevel Hadamard matrix according to an embodiment of the present invention.

In operation S101, the transmitting device 110 of the sensor system 100 according to an embodiment of the present disclosure divides the plurality of consecutive rows or columns of the first multilevel Hadamard matrix into at least one group.

In step S102, the transmitter 110 calculates a column sum or a row sum in the group divided in step S101, respectively.

In step S103, the transmitting device 110 generates a second multilevel Hadamard matrix using the column sum or row sum calculated in step S102. The rows of the second multilevel Hadamard matrix generated in step S103 correspond to individual channels, and the columns of the second multilevel Hadamard matrix represent the signs used at different times, or the columns of the second multilevel Hadamard matrix. Are corresponding to individual channels and the rows of the second multilevel Hadamard matrix may represent symbols used at different times. Further, each row of the second multilevel Hadamard matrix consists of a sum of a plurality of rows orthogonal to each other.

In operation S104, the transmitter 110 transforms the second multilevel Hadamard matrix by multiplying each row or each column of the generated second multilevel Hadamard matrix by a channel gain or a scale factor. Or you can simplify it.

In operation S105, the transmitter 110 generates a transmission signal by encoding the original signal based on the second multilevel Hadamard matrix generated in operation S103 or simplified in operation S104.

In step S106, the transmitting device 110 modulates the transmission signal generated in step S105.

In operation S107, the transmitter 110 transmits the modulated transmission signal to the transmission channel of the sensor system 100 at different times. Here, the transmitter 110 may transmit a transmission signal to a transmission channel of any one of a touch sensor system, a radar system, a lidar system, a visible light communication system, and an ultrasonic system.

8 is a flowchart illustrating a receiving method in a sensor system using a multilevel Hadamard matrix according to an embodiment of the present invention.

In step S201, the receiving device 120 of the sensor system 100 according to an embodiment of the present invention receives the received signal output from the sensing object.

In operation S202, the reception device 120 amplifies the received reception signal.

In operation S203, the receiving device 120 may demodulate the received signal received in operation S201 or demodulate the received signal amplified in operation S202.

In operation S204, the reception apparatus 120 demodulates a center row or a center column located in the center of each group of the second multilevel Hadamard matrix 310 as a decoding code based on the first multilevel Hadamard matrix 310. The received signal. In this case, the receiving device 120 uses the central row or the central column located in the center of each of the groups of the second multilevel Hadamard matrix 310 as the driving code to perform the dot product with the received signal. Can be.

In operation S205, the receiving device 120 may convert the decoded received signal into a digital signal through analog-digital conversion.

In operation S206, the receiving device 120 analyzes the decoded signal to calculate a physical quantity of the sensing object. Here, the received signal is a signal received after being transmitted to the sensing object after the transmission signal encoded based on the second multilevel Hadamard matrix is changed by the physical quantity of the sensing object.

9 is a diagram illustrating a correlation between a conventional Walsh Hadamard code including a modulation and demodulation, a basic multilevel Hadamard code, and a combined multilevel Hadamard code according to an embodiment of the present invention.

Since the modulated code is affected by the channel delay again, a phase difference occurs when the modulated signal is received in each code. That is, in order to maintain the merit of the code, the second multilevel Hadamard code 901 according to an embodiment of the present invention should compensate for the signal gain due to the phase difference when demodulating the modulated signal.

To this end, a signal demodulation process is performed on a single carrier frequency or a complex carrier frequency using a discrete fourier transform (DFT). In the DFT equation, the complex signal value corresponding to the modulation frequency bin may be separately calculated from the real part and the imaginary part, and then the size gain may be calculated again. Herein, when the carrier frequency of the detection signal y (t) is modulated to f _c , Equation 4 below may be applied to demodulate the modulated signal y _demod (t) having a code size of the component f _c .

Here, y _demod (t) represents a modulated signal, y (t) represents a sense signal, and f _c represents a carrier frequency.

The signal attenuation due to the phase difference generated between the sense signal y (t) and the sine wave of the carrier frequency f _c may be compensated for during the calculation of the real part and the imaginary part of Equation 4 and the magnitude calculation. Thereafter, a low pass filter (LPF) operation may be additionally performed to obtain a DC value. 9 includes a conventional Walsh Hadamard code 903, a first multilevel Hadamard code 902, and a second multilevel Hadamard code according to an embodiment of the present invention, when such modulation and demodulation processes are included. The result of comparing the correlation characteristic of (903) is shown. In contrast to the characteristics of the pure code of FIG. 5, the second multilevel Hadamard code 901 according to an embodiment of the present invention is secured to a similar level of code delay even when both modulation and demodulation processes are included. It can be seen.

10 to 14 show four types of active sensor systems to which embodiments of the present invention are applied.

10 is a diagram illustrating a configuration of a capacitive sensor system using a multilevel Hadamard matrix according to an embodiment of the present invention.

As shown in FIG. 10, the capacitive sensor system using the multilevel Hadamard matrix includes a driving signal generator 1010, a modulator 1020, a capacitive touch screen 1030, an amplifier 1040, and a demodulator. 1050 and a decoder 1060. Here, the transmitting device 110 according to an embodiment of the present invention may be implemented as the driving signal generator 1010 and the modulator 1020. The capacitive touch screen 1030 may correspond to the sensing object 101. The receiving device 120 may be implemented as the amplifier 1040, the demodulator 1050, and the decoder 1060. The modulator 1020 may include a plurality of modulators. The demodulator 1050 may include a plurality of demodulators, and the decoder 1060 may include a plurality of driving code internal parts for one to n / 3 rows.

Referring to the operation of the capacitive sensor system, the driving signal generated by the driving signal generator 1010 is input to the panel of the touch sensor provided in the capacitive touch screen 1030 that is a sensing object through the modulator 1020. The modulated signal entering the panel of the capacitive touch screen 1030 passes through the capacitive component and is output to each receiving end. Each received signal is input to the demodulator 1050 through the amplifier 1040. The demodulated received signals pass through a decoder 1060 for each row and converted into capacitances.

11 and 12 are views illustrating the configuration of a radar system and a lidar using a multilevel Hadamard matrix according to an embodiment of the present invention.

As shown in FIG. 11, the radar system 1100 using the multilevel Hadamard matrix includes a signal generator 1110, an encoder 1120, a transmitter 1130, a receiver 1140, an amplifier 1150, The filter 1160, the decoder 1170, the demodulator 1180, and the converter 1190 are included. Here, the transmitter 1130 and the receiver 1140 may be formed of a laser transmitter and a laser receiver, respectively. The transmitter 110 according to an exemplary embodiment of the present invention may be implemented as the signal generator 1110, the encoder 1120, and the transmitter 1130. In addition, the receiver 120 according to the embodiment of the present invention includes a receiver 1140, an amplifier 1150, a filter 1160, a decoder 1170, a demodulator 1180, and a converter 1190. It can be implemented together.

As shown in FIG. 12, the Lidar system 1200 using the multilevel Hadamard matrix includes a signal generator 1210, an encoder 1220, a transmitter 1230, a receiver 1240, and an amplifier 1250. The filter 1260 includes a decoder 1270, a demodulator 1280, and a converter 1290. Here, the transmitter 1230 and the receiver 1240 may be formed of a laser diode and a photodiode. The signal generator 1210, the encoder 1220, and the transmitter 1230 may be included in the transmitter 110 according to an embodiment of the present invention. In addition, the receiver 1240, the amplifier 1250, the filter 1260, the decoder 1270, the demodulator 1280, and the converter 1290 are connected to the receiver 120 according to an embodiment of the present invention. May be included.

In the radar system 1100 and the rider system 1200 of FIGS. 11 and 12, the encoders 1120 and 1220 are multilevel with respect to the s _{Tr _ i} signal, which is a specific transmission signal generated by the signal generators 1110 and 1210. Multiply the coded code using the Hadamard matrix. Subsequently, the transmitters 1130 and 1230 transmit signals multiplied by the coded codes.

Thereafter, the receivers 1140 and 1240 receive the received signal from the sensing object. The amplifiers 1150 and 1250 amplify the received signal, and the filter units 1160 and 1260 filter the amplified signal. The decoders 1170 and 1270 _{extract the} original received signal s _{Re _ i} by multiplying the corresponding decoding code by the signal filtered by the filtering units 1160 and 1260. The demodulators 1180 and 1280 mix the original signals as in the general radar method, and convert the digital signals into the digital signals in the converters 1190 and 1290 for analysis.

Here, the encoded code (Code Encoding) will be referred to as Ce, [Ce _{i, 1,} Ce _{i, 2,} ... ], The decoding code is represented by Cd, and [Cd _{i, 1} , Cd _{i, 2} ,... ] For example, when the coded code is generated from the multilevel Hadamard matrix of FIG. 3, the coded code may be represented as ([a + 2b], [3b], [3b], ...).

11 and 12, after a signal is modulated by the signal generators 1110 and 1210, encoding is performed by the encoders 1120 and 1220. After decoding by the decoders 1170 and 1270, demodulation is performed by the demodulators 1180 and 1280. On the other hand, the signals may be encoded by the encoders 1120 and 1220 and may be modulated by the signal generators 1110 and 1210. The received signals may be demodulated by the demodulators 1180 and 1280, and decoded by the decoders 1170 and 1270. That is, the order of the modulation and encoding processes may be changed, and the order of the decoding and demodulation processes may be changed.

FIG. 13 is a diagram illustrating a configuration of a visible light communication system using a multilevel Hadamard matrix according to an embodiment of the present invention.

As shown in FIG. 13, a visible light communication system using a multilevel Hadamard matrix includes an encoder 1310, a transmitter 1320, a receiver 1330, an amplifier 1340, a demodulator 1350, and a decoder ( 1360 and the conversion unit 1370. Here, the transmitter 1320 and the receiver 1330 may be formed of a light emitting diode and a photodiode, respectively. The sending device 110 according to an embodiment of the present invention may be implemented by an encoder 1310 and a transmitter 1320. In addition, the receiving apparatus according to the embodiment of the present invention may be implemented by a receiver 1330, an amplifier 1340, a demodulator 1350, a decoder 1360, and a converter 1370.

The plurality of encoders 1310 are S _i , S _j, and S _k , which are signals modulated with different codes, respectively. The coded codes corresponding to the signals [Ce _{i, 1} , Ce _{i, 2} ,... ], [Ce _{j, 1} , Ce _{j, 2} ,... ] And [Ce _{k, 1} , Ce _{k, 2} ,... ]. The transmitters 1320 transmit the encoded signals, respectively.

Thereafter, the receiver 1330 receives the combined received signal from the sensing object. The amplifier 1340 amplifies the combined received signals. The demodulator 1350 may demodulate only a corresponding signal from the amplified signal. The decoder 1360 may extract the original received signal by multiplying the demodulated signal by the demodulator 1350 with the corresponding decoding code, and the converter 1370 may convert the extracted signal into a digital signal and analyze the extracted signal.

14 is a diagram illustrating the configuration of an ultrasound system using a multilevel Hadamard matrix according to an embodiment of the present invention.

As shown in FIG. 14, the ultrasound system using the multilevel Hadamard matrix includes an encoder 1410, a first transducer 1420, a transmitter 1430, a receiver 1440, a second transducer 1450, The amplifier 1460 includes a demodulator 1470, a decoder 1480, and a converter 1490. Here, the first transducer 1420 may convert a transmission signal into an ultrasonic signal, and the second transducer 1450 may be a transducer that converts the received ultrasonic signal into a reception signal. The transmitting device 110 according to an embodiment of the present invention may be implemented by the encoder 1410, the first transducer 1420, and the transmitter 1430. In addition, the receiver 120 according to an exemplary embodiment of the present invention includes a receiver 1440, a second transducer 1450, an amplifier 1460, a demodulator 1470, a decoder 1480, and a converter 1490. ) Can be implemented.

The plurality of encoders 1410 transmits at most n / 3 different signals [Ce ₁ , ₁ , Ce _{1 , 2} ,... ], [Ce _{2 , 1} , Ce _{2 , 2} ,... ] And [Ce _{k / 3,1} , Ce _{k / 3,2} ,... Multiply by] and encode. The first transducer 1420 modulates the encoded signal and transmits the modulated signal through the transmitter 1430.

Thereafter, the receiver 1440 transmits the ultrasonic signal received from the sensing object to the second transducer 1450, and the second transducer 1450 converts the ultrasonic signal into a received signal. The amplifier 1460 may amplify the received signal, and the demodulator 1470 may demodulate the amplified signal. In addition, the decoder 1480 may perform the decoding codes corresponding to the signals demodulated by the demodulator 1470 such as [Cd _{1 , 1} , Cd _{1 , 2} ,... _{], [Cd 2, 1,} Cd 2, 2, ... ] And [Cd _{n / 3,1} , Cd _{n / 3,2} ,... Multiplying] to separate and extract n / 3 original received signals, and the converter 1490 may convert the extracted signal into a digital signal for analysis. Meanwhile, it is assumed that the encoding and decoding processes of FIGS. 13 and 14 include modulation and demodulation for convenience.

FIG. 15 is a diagram illustrating a method of reducing an interference rate of a code by applying a multilevel Hadamard matrix according to another embodiment of the present invention.

Since a general active sensor system including a rangefinder is inherently implemented together with a transmitting device and a receiving device, an effective time interval for detecting or synchronizing a detection signal at a receiving device can be defined from the moment when a transmitting signal is generated. For example, in a capacitive sensor and a visible light communication system, a stimulus signal is applied to a channel (for example, a TX-RX channel and an optical channel) and a detection signal that is delayed in channel characteristics is detected. For example, radar, lidar, and ultrasonic sensors measure the distance by applying a stimulus signal to a free-space channel and then measuring a detection signal that is reflected, delayed, and attenuated and returned to the target. Therefore, if the maximum time interval for synchronizing or detecting the detection signal from the time of generating the stimulus signal can be defined in advance as a system standard, in the embodiment of the present invention, when generating the second multilevel Hadamard matrix as shown in FIG. Measurement robustness can be ensured by matching the number of rows in the group with the maximum time delay.

In a multi-user environment such as vehicle lidar and radar, interference occurs between stimulus signals generated for each user. It is assumed that the probability of generating the stimulus signal of each user is uniformly distributed, and that each row code is used as the stimulus signal of the user in the second multilevel Hadamard matrix of the structure shown in FIG. 4. Then, the interference ratio of the second multilevel Hadamard code according to the embodiment of the present invention is expressed by Equation 5 below.

Here, T _g means the number of desired Hadamard matrices summed in one group, and T _code means the column length time length of the entire code.

Accordingly, the embodiment of the present invention generates a multilevel Hadamard matrix by increasing the order of the desired Hadamard code to minimize the number of combined rows in the group in order to be robust to signal interference of other users.

An example of applying the 9th-order Won Hadamard matrix and the 18th-order Won Hadamard matrix using three joining rows will be described with reference to FIGS. 15A and 15B. The column length time length 1501 of the entire code shown in FIG. 15A is 9, and the column length time length 1501 of the whole code shown in FIG. 15B is 18. FIG. In the case of the basic Hadamard matrix of 9th order, the signal interference ratio is 3/9, and the interference ratio is 3/18 in the case of the 18th order Hadamard matrix. Therefore, as illustrated in FIG. 15, it can be seen that the interference ratio of the 18th order matrix is reduced by half compared to the interference rate of the 9th order matrix.

FIG. 16 is a diagram illustrating a correlation diagram when a multilevel Hadamard matrix is modulated with a Barker-11 code according to an embodiment of the present invention. FIG.

In addition, in the rangefinder sensor, a method of measuring ToF (Time-of-Flight) of a transmission signal by detecting or synchronizing the autocorrelation of the reception signal is widely used. The rangefinder sensor system according to an embodiment of the present invention uses magnetic signals such as a Barker code or a CSS code instead of modulating each code a + b + b and b + b + b shown in FIG. 4 with the same signal frequency. By further modulating the code with excellent correlation, it can be utilized to more easily detect autocorrelation peaks. As an example, the rangefinder sensor system according to an embodiment of the present invention modulates each code of FIG. 4 to a Barker-11 code [-1 -1 -1 1 1 1 -1 1 1 -1 1], and likewise, When decoding to the middle row, as shown in Fig. 16, three autocorrelation peaks of the same size can be secured and used for signal measurement. This peak signal appears to be completely orthogonal to the autocorrelation peak signal of the other channel.

Although described above with reference to the drawings and embodiments, it does not mean that the scope of protection of the present invention is limited by the above drawings or embodiments, and those skilled in the art to the spirit of the present invention described in the claims It will be understood that various modifications and variations can be made in the present invention without departing from the scope of the invention.

100: sensor system
110: transmitting device
111: matrix calculation unit
112: matrix generator
113: signal generator
114, 1020: modulator
115: transmitter
120: receiving device
121: calculating unit
122, 1190, 1290, 1370, 1490: converter
123, 1060, 1170, 1270, 1360, 1480: decoder
124, 1050, 1180, 1280, 1350, 1470: demodulator
125, 1040, 1150, 1250, 1340, 1460: amplifier
126: receiver
1010: driving signal generator
1110 and 1210: signal generator
1120, 1220, 1310, and 1410: encoder
1130, 1230, 1320, 1430: transmitter
1140, 1240, 1330, 1440: Receiver
1160 and 1260: filtering unit
1420 and 1450: first and second transducers

Claims (20)

In the transmission method performed by the transmission device of the sensor system,
Dividing the plurality of consecutive rows or columns of the first multilevel Hadamard matrix into at least one group, and calculating column sums or row sums in the divided groups, respectively;
Generating a second multilevel Hadamard matrix using the calculated column sum or row sum; And
And transmitting the original signal based on the generated second multilevel Hadamard matrix to generate a transmission signal. The method of claim 1,
And modifying or simplifying the second multilevel Hadamard matrix by multiplying each row or each column of the generated second multilevel Hadamard matrix by a channel gain or a scale factor. A method for transmitting a sensor system using a multilevel Hadamard matrix. The method of claim 1,
Modulating the generated transmission signal; And
And transmitting the modulated transmission signal at different times in a transmission channel of the sensor system. The method of claim 3,
The sensor system,
A method of transmitting a sensor system using a multilevel Hadamard matrix comprising any one of a touch sensor system, a radar system, a lidar system, a visible light communication system, and an ultrasonic system. The method of claim 3,
The rows of the second multilevel Hadamard matrix correspond to individual channels of the transmission channel and the columns of the second multilevel Hadamard matrix represent symbols used at different times when encoding the original signal, or A column of a second multilevel Hadamard matrix corresponds to an individual channel of the transmission channel and the rows of the second multilevel Hadamard matrix represent multilevel Hadamards representing codes used at different times when encoding the original signal. Method of transmitting sensor system using matrix. The method of claim 1,
When the first multilevel Hadamard matrix is an n-th order multilevel Hadamard matrix, the diagonal component of the matrix is a component and the remaining components except the diagonal component are b components, and the sum of columns of the first multilevel Hadamard matrix Or, if the row sum is m, a = m (2 / n-1) and b = 2m / n, the transmission method of the sensor system using the multilevel Hadamard matrix. In the receiving method performed by the receiving device of the sensor system,
Receiving a received signal output from the sensing object;
Demodulating the received received signal;
Decoding the demodulated received signal using a center row or a center column located in the center of each group of the second multilevel Hadamard matrix as a decoding code based on a first multilevel Hadamard matrix; And
Calculating a physical quantity of the detection object by analyzing the decoded signal,
The received signal is a signal in which a transmission signal encoded based on the second multilevel Hadamard matrix is changed by a physical quantity of the sensing object, and is received.
Each group of the second multilevel Hadamard matrix represents at least one group grouped by a plurality of consecutive rows or columns of the first multilevel Hadamard matrix, and the physical quantity of the sensing object is the encoded transmission signal. A method of receiving a sensor system using a multilevel Hadamard matrix, characterized by indicating that the transmission signal changes after being transmitted to the sensing object. The method of claim 7, wherein
Amplifying the received received signal;
The demodulating step is a method of receiving a sensor system using a multilevel Hadamard matrix for demodulating the amplified received signal. The method of claim 7, wherein
And converting the decoded received signal into a digital signal through an analog-to-digital conversion. The method of claim 7, wherein
The decoding step,
Using the multilevel Hadamard matrix, the received signal is decoded by internally substituting the central row or the central column located in the center of each group of the second multilevel Hadamard matrix with the received signal. Receiving method of the sensor system. A matrix calculator configured to group a plurality of consecutive rows or columns of a first multilevel Hadamard matrix into at least one group, and to calculate column sums or row sums within the divided groups;
A matrix generator configured to generate a second multilevel Hadamard matrix using the calculated column sum or row sum; And
And a signal generator for generating a transmission signal by encoding an original signal based on the generated second multilevel Hadamard matrix. The method of claim 11,
The matrix generator,
A multilevel Hadamard matrix for transforming or simplifying the second multilevel Hadamard matrix by multiplying each row or column of the generated second multilevel Hadamard matrix by a channel gain or a scale factor, respectively. Transmitter of the sensor system using the. The method of claim 11,
A modulator for modulating the encoded transmission signal; And
And a transmitter configured to transmit the modulated transmission signal to the transmission channel of the sensor system at different times. The method of claim 13,
The sensor system,
An apparatus for transmitting a sensor system using a multilevel Hadamard matrix, comprising any one of a touch sensor system, a radar system, a lidar system, a visible light communication system, and an ultrasonic system. The method of claim 13,
The rows of the second multilevel Hadamard matrix correspond to individual channels of the transmission channel and the columns of the second multilevel Hadamard matrix represent symbols used at different times when encoding the original signal, or A column of a second multilevel Hadamard matrix corresponds to an individual channel of the transmission channel and the rows of the second multilevel Hadamard matrix represent multilevel Hadamards representing codes used at different times when encoding the original signal. Transmitter of sensor system using matrix. The method of claim 11,
When the first multilevel Hadamard matrix is an n-th order multilevel Hadamard matrix, the diagonal component of the matrix is a component and the remaining components except the diagonal component are b components, and the sum of columns of the first multilevel Hadamard matrix Or when the row sum is m, a = m (2 / n-1) and b = 2m / n. Receiving unit for receiving the received signal output from the sensing object;
A demodulator for demodulating the received received signal;
A decoder which decodes the demodulated received signal using a center row or a center column located in the center of each group of the second multilevel Hadamard matrix as a decoding code based on a first multilevel Hadamard matrix; And
A calculation unit configured to analyze the decoded signal and calculate a physical quantity of the detection object;
The received signal is a signal in which a transmission signal encoded based on the second multilevel Hadamard matrix is changed by a physical quantity of the sensing object, and is received.
Each group of the second multilevel Hadamard matrix represents at least one group grouped by a plurality of consecutive rows or columns of the first multilevel Hadamard matrix, and the physical quantity of the sensing object is the encoded transmission signal. Receiving apparatus of a sensor system using a multilevel Hadamard matrix, characterized in that it indicates that the transmission signal changes after being transmitted to the sensing object. The method of claim 17,
Further comprising an amplifier for amplifying the received received signal,
And a demodulator demodulating the amplified received signal using a multilevel Hadamard matrix. The method of claim 17,
And a converter for converting the decoded received signal into a digital signal through analog-digital conversion. The method of claim 17,
The decoding unit,
Using the multilevel Hadamard matrix, the received signal is decoded by internally substituting the central row or the central column located in the center of each group of the second multilevel Hadamard matrix with the received signal. Receiving device of the sensor system.

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