KR102492214B1 - Apparatus and method for determining position - Google Patents

Abstract

The present disclosure relates to a positioning device and method, and in particular, it is possible to provide a positioning device and method capable of estimating an accurate position by removing the CRI effect of a signal and estimating an accurate TOA value. In addition, a positioning device and method capable of improving TOA measurement performance can be provided by considering Doppler and oscillator frequency errors through linear function modeling and the least squares method.

Description

Positioning device and method {APPARATUS AND METHOD FOR DETERMINING POSITION}

The present embodiments relate to a positioning device and method.

Loran (Long RANge Navigation) is a long-distance radio navigation system that calculates the user's position by using the time when three or more pulse signals transmitted from different transmitters arrive at the receiver with an agreed cycle and delay time. It is a positioning system that has a wide range of applications, such as aircraft.

However, since Loran uses a periodic pulse signal and signals having different periods exist in the channel, inter-signal interference occurs intermittently, and thus an error of several kilometers frequently occurs. Therefore, a positioning technology capable of solving these problems and providing precise location information is required.

Against this background, the present embodiments intend to propose a positioning device and method capable of estimating an accurate position by suppressing the effect of inter-signal interference.

In order to achieve the above object, in one aspect, the present embodiments determine whether cross-rate interference (CRI) occurs using information on the magnitude of a received signal received by a receiver, and calculates the CRI result value according to the determination result. A CRI detection unit that outputs, a signal prediction unit that converts the phase measurement value calculated from the reference output signal and the received signal into an arrival time error using the CRI result value, and predicts the predicted arrival time of the signal using the arrival time error, and TOA (Time of arrival) A positioning device comprising a TOA estimation unit that calculates an estimation parameter using a measured value and a pulse period of a received signal, and estimates a TOA estimation value of an estimated time of arrival using the estimation parameter. can

In another aspect, the present embodiments include a CRI detection step of determining whether cross-rate interference (CRI) occurs using information on the magnitude of a received signal received by a receiver and outputting a CRI result value according to the determination result, CRI result A signal prediction step of converting the phase measurement value calculated from the reference output signal and the received signal into an arrival time error using the values and predicting the arrival time of the signal using the arrival time error and the TOA (Time of arrival) measurement value and a TOA estimation step of calculating an estimation parameter using the pulse period of the received signal and estimating a TOA estimation value of the predicted arrival time using the estimation parameter.

According to the present embodiments, it is possible to provide a positioning device and method capable of estimating an accurate position by suppressing the effect of inter-signal interference.

1 is a diagram exemplarily illustrating the configuration of a positioning device according to an embodiment of the present disclosure.
2 is a flowchart illustrating an entire operation of a positioning device according to an embodiment of the present disclosure.
3 is a flowchart illustrating an operation of calculating a TOA measurement value of a positioning device according to an embodiment of the present disclosure.
4 is a flowchart illustrating a standard score calculation operation for CRI detection of a positioning device according to an embodiment of the present disclosure.
5 is a flowchart illustrating a CRI detection operation of a positioning device according to an embodiment of the present disclosure.
6 is a flowchart illustrating an operation of calculating an estimated TOA value of a positioning device according to an embodiment of the present disclosure.
7 is a diagram for explaining CRI detection and TOA estimation effects of a positioning device according to an embodiment of the present disclosure.
8 is a flowchart of a positioning method according to an embodiment of the present disclosure.

Hereinafter, some embodiments of the present disclosure will be described in detail with reference to exemplary drawings. In adding reference numerals to components of each drawing, the same components may have the same numerals as much as possible even if they are displayed on different drawings. In addition, in describing the present embodiments, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the present technical idea, the detailed description may be omitted. When "comprises", "has", "consists of", etc. mentioned in this specification is used, other parts may be added unless "only" is used. In the case where a component is expressed in the singular, it may include the case of including the plural unless otherwise explicitly stated.

Also, terms such as first, second, A, B, (a), and (b) may be used in describing the components of the present disclosure. These terms are only used to distinguish the component from other components, and the nature, sequence, order, or number of the corresponding component is not limited by the term.

In the description of the positional relationship of components, when it is described that two or more components are "connected", "coupled" or "connected", the two or more components are directly "connected", "coupled" or "connected". ", but it will be understood that two or more components and other components may be further "interposed" and "connected", "coupled" or "connected". Here, other components may be included in one or more of two or more components that are “connected”, “coupled” or “connected” to each other.

In the description of the temporal flow relationship related to components, operation methods, production methods, etc., for example, "after", "continued to", "after", "before", etc. Alternatively, when a flow sequence relationship is described, it may also include non-continuous cases unless “immediately” or “directly” is used.

On the other hand, when a numerical value or corresponding information (eg, level, etc.) for a component is mentioned, even if there is no separate explicit description, the numerical value or its corresponding information is not indicated by various factors (eg, process factors, internal or external shocks, noise, etc.) may be interpreted as including an error range that may occur.

In this specification, the Loran (Long RANge Navigation) system utilizes a low-frequency pulse signal of 100 kHz to operate the receiver to measure the pseudorange. can have cycles. Also, a chain can consist of one master station and two or more secondary stations. Specifically, in Korea, 9930 chains (9930W in Gwangju based on 9930 master transmission station in Pohang, 9930V test transmission station in Incheon, signal transmission with a period of 99,300us) are in operation, and 7430 and 8390 chains operated in China are received domestically. can do.

Cross-rate interference (CRI) in this specification may mean inter-signal interference that intermittently occurs between signals as multiple chains operate with different cycles. For example, CRI may occur when signals overlap at times corresponding to least common multiples of each period. If a phase error is generated by CRI, the worst case can lead to cycle slip, which can cause several kilometers of navigation error.

In addition, TOA (Time of arrival) in this specification is the arrival time of radio waves and may mean a certain spherical trajectory in a base station. Specifically, if the distance between the transmitter and the receiver is d, the relationship between the propagated time and the distance can be said to be d = cτ. In this case, τ may mean propagation delay time, and c may mean propagation speed (3×10 ⁸ m/s). Therefore, the distance measurement value can be obtained by multiplying the receiver's TOA measurement value, which is the arrival time of the radio wave, by the speed of light.

1 is a diagram exemplarily illustrating the configuration of a positioning device according to an embodiment of the present disclosure.

Referring to FIG. 1, the positioning device 100 according to an embodiment of the present disclosure determines whether cross-rate interference (CRI) occurs using information on the magnitude of a received signal received by a receiver, and according to the determination result The CRI detection unit 110 outputs the CRI result value, converts the phase measurement value calculated from the reference output signal and the received signal into an arrival time error using the CRI result value, and predicts signal arrival using the converted arrival time error. TOA estimation that calculates an estimation parameter using the signal prediction unit 120 that predicts the time and the TOA (Time of Arrival) measurement value and the pulse period of the received signal, and estimates the TOA estimation value of the predicted arrival time using the estimation parameter. Government 130 may be included.

The CRI detection unit 110 may determine whether CRI is generated by using magnitude information of a received signal received by the receiver. For example, the CRI detecting unit 110 may determine whether CRI occurs by using a phenomenon in which the amplitude of a signal increases or decreases according to the phases of two pulse signals when inter-signal interference occurs.

The CRI detection unit 110 may obtain magnitude information of the received signal by calculating two correlation values of the in-phase and quadrature-phase of the signal as an RMS value. In addition, the CRI detection unit 110 calculates a standard score (Z-value) using the average and standard deviation of the magnitude included in the magnitude information of the received signal, and determines whether or not the CRI occurs from the standard score calculated using the reference value. can judge For example, the CRI detection unit 110 may calculate an average and a standard deviation of received signal amplitudes using received signal amplitude measurement values collected during a certain period of time. In addition, the CRI detection unit 110 may convert the average and standard deviation of the calculated received signal strength into standard scores (Z-values). Here, the standard score (Z-value) may be a dimensionless numerical value as an index indicating how much the currently measured received signal level is on the standard deviation in the signal level distribution. In addition, the standard score may be a numerical value indicating how far the currently measured magnitude of the received signal is from the average. Accordingly, the CRI detection unit 110 may predict that CRI has occurred when the converted standard score corresponds to a reference value or higher.

The CRI detection unit 110 may output a CRI result value according to the CRI determination result. For example, the CRI detection unit 110 may output CRI result values as 0 and 1 according to the CRI determination result. For example, the CRI detecting unit 110 may determine that CRI has occurred when the calculated standard score corresponds to a reference value or higher, and output a CRI result value of 0 when it is determined that CRI has occurred. On the other hand, the CRI detection unit 110 may determine that CRI does not occur when the calculated standard score is less than the reference value, and output a CRI result value of 1 when it is determined that CRI does not occur. The CRI result value can be used to determine whether to use the loop filter output value of pulse signal tracking or to determine the weight of the TOA measurement value.

The signal predictor 120 may convert the phase measurement value calculated from the reference output signal and the received signal into an arrival time error using the CRI result value. For example, the signal predictor 120 may obtain a phase difference using an in-phase correlation value and a quadrature-phase correlation value between the reference output signal and the received signal. Also, the signal predictor 120 may calculate a phase measurement value from which noise is removed by using a loop filter from the acquired phase difference. For example, the signal predictor 120 may include a correlator, a phase measurement, and a loop filter. Specifically, when the signal predictor 120 inputs a digital signal sample for about 250us from the expected arrival time of the received signal, the pulse signal, to the correlator, the phase difference between the 100kHz carrier, which is the reference output signal, and the input pulse signal. can be obtained In addition, the obtained phase difference may pass through a loop filter to calculate a phase measurement value in which measurement noise is alleviated.

The signal predictor 120 may predict the predicted arrival time of the signal using the arrival time error. For example, the signal predictor 120 may determine whether to convert the arrival time error using a value obtained by multiplying the CRI result value and the phase measurement value, and convert the arrival time error into an arrival time error. For example, if the signal predictor 120 determines that CRI is not generated and outputs a CRI result value as 1, the loop filter output may not be affected. On the other hand, if the signal predictor 120 determines that CRI is generated and outputs the CRI result value as 0, the loop filter output value becomes 0 and does not affect the next value, so that the CRI blanking effect can be obtained. In addition, the signal predictor 120 may predict the predicted arrival time by using the converted arrival time error with the current arrival time and the pulse period of the received signal.

The TOA estimator 130 may calculate an estimation parameter using a time of arrival (TOA) measurement value and a pulse period of a received signal. For example, the TOA estimator 130 may calculate a TOA measurement value using a pulse period from a current arrival time and an arrival time error, and calculate estimated parameters by modeling the TOA measurement value. For example, the TOA estimator 130 may calculate the TOA measurement value with a residual value obtained by compensating the current pulse arrival time with an arrival time error and dividing it by the pulse period. Specifically, since the TOA measurement value can be acquired once per pulse, it can be about 10 to 20 per second.

In addition, since the calculated TOA measurement value increases or decreases with time, the TOA estimation unit 130 can be modeled as a linear function, and since the measurement time has a pulse period interval, it is estimated from an equation modeled using a pulse period. parameters can be calculated. Here, the calculated estimated parameter may include a parameter meaning a change amount of the TOA measurement value and a parameter meaning a bias.

In addition, the TOA estimator 130 may calculate an estimation parameter through a least squares method if there are N or more TOA measurement values (where N is a natural number equal to or greater than 2). For example, the TOA estimator 130 applies a weight matrix to a measurement vector generated using N (N is a natural number of 2 or more) or more TOA measurement values and a measurement time matrix generated using a pulse period to obtain an estimation parameter. can be calculated For example, the weight matrix may be generated in the form of a diagonal matrix using CRI result values corresponding to TOA measurement values. Here, CRI is generated for the weight matrix, and when the CRI result value is 0, an effect of being excluded from the least squares method can be obtained.

Also, the TOA estimator 130 may estimate a TOA estimation value of the predicted arrival time using the calculated estimation parameter. For example, the TOA estimator 130 may estimate a TOA estimation value of a predicted arrival time suitable for a desired measurement period using the calculated estimation parameter.

2 is a flowchart illustrating an entire operation of a positioning device according to an embodiment of the present disclosure.

Referring to FIG. 2 , an example of an entire operation for estimating the TOA estimation value of the positioning device 100 will be described. The CRI detection unit 210 of the positioning device 100 may use the received signal received by the receiver and input it to the pulse signal waiting block (S210). For example, the CRI detection unit 210 may receive a pulse emitted from a primary station through a receiver, input a pulse signal waiting block to search for a pulse signal generation time, and wait.

The CRI detector 210 may calculate a correlation value of the received signal using a correlator (S220). For example, the CRI detection unit 210 may calculate the magnitude of the received signal by calculating the RMS of the correlation value separated into an in-phase signal and a quadrature-phase signal.

The CRI detection unit 210 may determine whether CRI has occurred using a standard score calculated from the magnitude of the received signal (S230). For example, the CRI detection unit 210 may predict that CRI has occurred when a standard score higher than a reference value is calculated due to a change in magnitude of the received signal. Details on outputting and using the CRI result value according to whether CRI occurs will be described later with reference to FIGS. 4 and 5 .

The signal predictor 220 may estimate an arrival time error by calculating a phase measurement value (S240). For example, the signal predictor 220 may obtain a phase difference between the carrier generated by the correlator and the received signal. The phase difference can be obtained using Equation 1.

Here, Q is a quadrature-phase correlation value, and I may mean an in-phase correlation value. In addition, the signal predictor 220 may calculate a phase measurement value from which a noise component of the phase error is removed from the obtained phase difference using a loop filter. The loop filter can be expressed as Equation 2.

는 위상차를 의미하고, α₀, α₁는 루프 필터 계수를 의미할 수 있다. 또한, 신호 예측부(220)는 산출된 위상 측정값은 수학식 3을 이용하여 현재 펄스 도달 시각 오차로 변환할 수 있다. here,

denotes a phase difference, and α ₀ and α ₁ may denote loop filter coefficients. In addition, the signal predictor 220 may convert the calculated phase measurement value into a current pulse arrival time error using Equation 3.

는 위상 측정값을 의미하고 f_c는 펄스 발생 주파수를 의미할 수 있다. 다만, f_c는 100kHz 일 수 있으나, 이에 한정되지 않는다. 이렇게 산출된 현재의 펄스 도달 시각 오차는 다음 펄스의 도달 예측 시각을 예측하는데 사용될 수 있다. 또한, 도달 예측 시각은 수학식 4와 같이 표현할 수 있다. here,

may mean a phase measurement value and f _c may mean a pulse generation frequency. However, f _c may be 100 kHz, but is not limited thereto. The current pulse arrival time error calculated in this way can be used to predict the arrival prediction time of the next pulse. In addition, the predicted arrival time can be expressed as Equation 4.

Here, t _n is the arrival time of the current pulse, t _n+1 is the predicted arrival time of the next pulse, and δt _n may mean an arrival time error. T _GRI may mean a pulse generation period.

과 CRI 결과 값을 곱해서 도달 시각 오차의 변환 여부를 결정할 수 있다. 따라서, CRI 결과 값이 1로 출력되면 루프 필터 출력에 영향을 주지 않지만, CRI 결과 값이 0으로 출력되면 위상 측정값이 0이 되어 다음 보정 값에 영향을 주지 않을 수 있다. 즉, 신호 예측부(220)는 CRI blanking 효과를 얻을 수 있다. The signal predictor 220 outputs the phase measurement value of the loop filter.

It is possible to determine whether to convert the time-of-arrival error by multiplying by the resultant value of CRI and . Accordingly, if the CRI result value is output as 1, the loop filter output is not affected, but if the CRI result value is output as 0, the phase measurement value becomes 0 and may not affect the next correction value. That is, the signal predictor 220 may obtain a CRI blanking effect.

The TOA estimator 230 may calculate an estimated parameter using a time of arrival (TOA) measurement value, and estimate a TOA estimated value from the calculated estimated parameter (S250). For example, the TOA estimator 230 may obtain a time of arrival (TOA) measurement value through a pulse signal tracking process. For example, the TOA estimator 230 may compensate for the arrival time of the current pulse with an arrival time error and obtain the TOA measurement value with a remainder obtained by dividing the current pulse by the pulse generation period. The TOA measurement value can be obtained using Equation 5.

Also, the TOA estimator 230 may model a TOA measurement value that increases or decreases with time as a linear function. Since the measurement time has a pulse generation period interval, the modeled TOA measurement value can be expressed as in Equation 6.

Here, a may be an estimation parameter denoting a variation of the TOA measurement value, and b may be an estimation parameter denoting a bias.

The TOA estimation unit 230 may estimate a TOA estimation value suitable for a desired measurement period, t _k , by using the estimation parameters calculated from modeling. The estimated TOA value can be estimated using Equation 7.

Here, t _k may mean a location calculation time. For example, if the receiver estimates the position at a period of 1 Hz, t _k -t _{k -1} may be 1. Therefore, in the case of Loran, since the measurement period of each pulse signal is not a divisor of 1, an effect of compensating with an estimated value of 1 second period may be obtained.

3 is a flowchart illustrating an operation of calculating a TOA measurement value of a positioning device according to an embodiment of the present disclosure.

Referring to FIG. 3 , an example of an operation of calculating a TOA measurement value and a TOA weight for estimating the TOA estimation value of the positioning device 100 will be described. For example, the CRI detection unit 210 may input the predicted arrival time of the next pulse signal to the pulse signal waiting block (S310). For example, the CRI detector 210 may obtain a sample of the next pulse signal from the pulse signal waiting block.

The CRI detector 210 may output an in-phase correlation value with the carrier by inputting a sample of the next pulse signal to the correlator (S320). For example, the CRI detector 210 may input the digital signal sample to the correlator for about 250 us from the expected arrival time of the pulse signal. Also, the CRI detection unit 210 may generate an in-phase signal of a digital carrier wave, mix it with a pulse signal part, and accumulate it when a pulse signal is received. At this time, the calculated value may be an in-phase correlation value.

The CRI detector 210 may output a quadrature-phase correlation value with the carrier by inputting a sample of the next pulse signal to the correlator (S330). For example, the CRI detector 210 may generate a quadrature-phase signal of a digital carrier, mix it with a pulse signal part, and accumulate it when a pulse signal comes in. In this case, the calculated value may be a quadrature-phase correlation value.

The CRI detection unit 210 may calculate signal amplitude information using an RMS value of a correlation value of an in-phase signal and a correlation value of a quadrature-phase signal (S340). For example, the CRI detection unit 210 may obtain a standard score by calculating an average and a standard deviation using size information calculated for a certain period of time.

The CRI detection unit 210 may detect whether CRI has occurred using a standard score (S350). For example, the CRI detection unit 210 may determine whether CRI has occurred by using a standard score obtained from signal magnitude information. This is because the magnitude of the signal changes as CRI occurs and a high standard score is output.

The signal prediction unit 220 may calculate the phase difference of the signal from the correlation value of the in-phase signal and the correlation value of the quadrature-phase signal (S360). For example, the signal prediction unit 220 may calculate the phase difference of the signal from the correlation value of the in-phase signal and the correlation value of the quadrature-phase signal using the ATAN2 function. In this case, the calculated phase difference may mean an error.

The signal predictor 220 may calculate a phase measurement value from the phase difference using a loop filter (S370). For example, the signal predictor 220 may use a loop filter having a low pass filter (LPF) structure to calculate a phase measurement value obtained by removing a high frequency component generated during a loop operation.

The TOA estimator 230 may obtain a TOA measurement value in which measurement noise and CRI effects are mitigated (S380). For example, the TOA estimator 230 may obtain a TOA measurement value from a current pulse arrival time in which an arrival time error in which the CRI effect is mitigated is reflected by using the CRI resultant value. In addition, the TOA measurement value may be input again to the pulse signal waiting block by calculating the expected arrival time of the next pulse. This may provide an effect of determining whether or not to use the feedback value according to the CRI result value.

The TOA estimator 230 may obtain a TOA weight value in which the CRI result value is reflected (S390). For example, when there are two or more TOA measurement values, the TOA estimator 230 may obtain a weight matrix in which CRI result values are composed of diagonal components.

4 is a flowchart illustrating a standard score calculation operation for CRI detection of a positioning device according to an embodiment of the present disclosure.

Referring to FIG. 4 , an example of an operation of calculating a standard score in order for the CRI detection unit 210 of the positioning device 100 to determine whether CRI has occurred will be described. For example, the CRI detection unit 210 may measure the magnitude of the received signal received from the receiver (S410). In addition, the CRI detection unit 210 may calculate the magnitude of the received signal as an RMS value of two correlation values of the in-phase and quadrature-phase of the received signal.

The CRI detection unit 210 may compare the current buffer size and the total buffer size to store size information of the new received signal (S420). For example, the buffer size may mean a space or time to temporarily store while information is fetched from a network.

If the CRI detection unit 210 determines that the current buffer size is greater than the total buffer size, it can delete the oldest size information (S430). For example, the CRI detector 210 may calculate the magnitude of the received signal using the correlation value and store it in a buffer. However, the CRI detection unit 210 may delete size information having the longest stored period when it is determined that the storage space of the current buffer is insufficient. On the other hand, if the CRI detection unit 210 determines that the current buffer size is smaller than the total buffer size, it may add the calculated size information to the buffer (S440).

The CRI detector 210 may calculate an average and a standard deviation of magnitudes of received signals collected during a certain period of time (S450). For example, the CRI detection unit 210 may collect magnitude information of about 500 received signals for a period of about 1 minute and calculate an average and standard deviation of magnitudes. However, 1 minute or 500 is for explaining an example and is not limited thereto.

The CRI detection unit 210 may convert the average and standard deviation of the amplitude of the received signal into a standard score (Z-value) (S460). For example, the CRI detection unit 210 may obtain a deviation from the average from the magnitude of each received signal and convert it into a standard score by dividing by the standard deviation. In this case, the standard score may be a conversion score having an average of 0 and a standard deviation of 1 under the assumption that the size distribution of the received signal is a normal distribution. Therefore, the CRI detection unit 210 can apply the same reference value regardless of the state of the received signal by using the standard score, thereby providing an active response to the signal state.

5 is a flowchart illustrating a CRI detection operation of a positioning device according to an embodiment of the present disclosure.

Referring to FIG. 5 , an example of an operation in which the CRI detection unit 210 of the positioning device 100 outputs a CRI result value according to a result of determining whether CRI has occurred will be described. For example, the CRI detection unit 210 may convert the average and standard deviation of magnitudes of the received signal into a standard score (Z-value) (S460). The CRI detection unit 210 may compare the converted standard score with a preset reference value to determine whether CRI has occurred (S510). For example, the CRI detection unit 210 may output a converted standard score of 2.0 or higher when the CRI is generated. Accordingly, the CRI detection unit 210 may preset a reference value to be 2.0 as a criterion for determining whether CRI has occurred and compare the result with the converted standard score.

The CRI detection unit 210 may output a CRI result value as 1 when the converted standard score is less than the reference value (S520). For example, the CRI detection unit 210 may determine that no CRI has occurred and output a CRI result value of 1 when the converted standard score is less than the reference value of 2.0.

On the other hand, the CRI detection unit 210 may output a CRI result value as 0 when the converted standard score corresponds to a reference value or higher (S530). For example, the CRI detection unit 210 may determine that CRI has occurred when the converted standard score corresponds to a reference value of 2.0 or more, and output a CRI result value of 0. Accordingly, the CRI detector 210 may provide a CRI response effect equivalent to the CRI blanking level without correcting the arrival time error. In addition, the positioning device can provide an effect that it is not necessary to predict the overlapping time of signals.

6 is a flowchart illustrating an operation of calculating an estimated TOA value of a positioning device according to an embodiment of the present disclosure.

Referring to FIG. 6 , an example of an operation of estimating a TOA estimation value by the TOA estimation unit 230 of the positioning device 100 will be described. For example, the TOA estimation unit 230 may receive a TOA measurement value and a TOA weight in which the CRI result value is reflected (S610). For example, the TOA measurement value may be obtained using an arrival time error in which a CRI result value is reflected. Also, the TOA weight may be composed of CRI result values.

The TOA estimator 230 may compare the current buffer size and the total buffer size to store the TOA estimation value and the TOA weight (S620). For example, the TOA estimator 230 may determine whether to store the new TOA estimation value and the TOA weight by determining whether the current buffer size is smaller than the total buffer size.

If the TOA estimator 230 determines that the current buffer size is greater than the total buffer size, it can delete the oldest TOA estimation value and TOA weight (S630). On the other hand, if the TOA estimator 230 determines that the current buffer size is smaller than the total buffer size, it may add a new TOA estimation value and TOA weight to the buffer (S640).

The TOA estimator 230 may generate a measurement time matrix (S650). For example, if there are two or more TOA measurement values, the TOA estimation unit 230 may generate a measurement time matrix using a pulse generation period based on the accumulated number of TOA measurement values. The generated measurement time matrix can be expressed as Equation 8.

Here, L may mean the accumulated number of measured values, and T _GRI may mean a pulse generation period.

The TOA estimator 230 may generate a TOA measurement vector (S660). For example, the TOA estimator 230 may generate a vector matrix composed of TOA measurement values. Here, the vector matrix may mean a column vector. The generated TOA measurement vector can be expressed as in Equation 9.

은 TOA 측정값을 의미할 수 있다. here,

may mean a TOA measurement value.

The TOA estimator 230 may generate a weight matrix (S670). For example, the TOA estimator 230 may generate a weight matrix composed of CRI result values and apply it to the measurement time matrix and the TOA measurement vector. For example, the weight matrix may be generated in the form of a diagonal matrix in which diagonal elements are 0 or 1. That is, the TOA estimator 230 may generate a weight matrix in the form of a diagonal matrix having CRI result values corresponding to TOA measurement values as diagonal components. As a specific example, when the diagonal component of the weight matrix is 0, it means that CRI is generated and may provide an effect of being excluded from the least square method operation. The generated weight matrix can be expressed as Equation 10.

The TOA estimator 230 may calculate estimated parameters (S680). For example, the TOA estimator 230 may calculate the estimated parameters using the least squares method. The estimation parameter may be composed of a variation parameter of the TOA measurement value and a bias parameter. For example, if the TOA measurement value model corresponds to a linear model and there are two or more measurement values, the TOA estimation unit 230 may calculate an estimation parameter using the least squares method. Also, the TOA estimator 230 may use a measurement time matrix and a TOA measurement vector to calculate an estimation parameter. Since the estimated parameters are composed of two parameters, Equation 11 must be satisfied. When Equation 11 is satisfied, it can be calculated using Equation 12.

The TOA estimation unit 230 may estimate the TOA estimation value (S690). For example, the TOA estimator 230 may estimate a TOA estimation value using the calculated estimation parameter. For example, the TOA estimator 230 may estimate a TOA estimation value suitable for a desired measurement period using the estimation parameter calculated from Equation 7. The estimated TOA estimate is a TOA value from which the CRI effect has been removed, and a precise position can be calculated.

7 is a diagram for explaining CRI detection and TOA estimation effects of a positioning device according to an embodiment of the present disclosure.

Referring to FIG. 7 , an example of CRI detection and TOA estimation effects of the positioning device 100 will be described. As an example, FIG. 7 is a diagram generated with TOA measurement values measured at T _GRI , which is a pulse generation period. Here, the TOA measurement value having a weight of 0 may mean a TOA measurement value when CRI is generated. For example, in the case of a TOA measurement value having a weight of 0, the CRI detecting unit 210 may detect the occurrence of CRI at the corresponding measurement time, and the TOA estimating unit 230 may exclude the TOA estimation value at the corresponding measurement time. .

For example, the positioning device 100 may obtain a TOA estimation function by obtaining a TOA model using a TOA measurement value having a weight of 1 and a measurement time. In this case, the position estimation period of the receiver may have a time between t _k and t _k−1 . Also, since T _GRI may not be a divisor of the period, a TOA value corresponding to T _k may be predicted.

Hereinafter, a positioning method that can be performed by the positioning device described with reference to FIGS. 1 to 7 will be described.

8 is a flowchart of a positioning method according to an embodiment of the present disclosure.

Referring to FIG. 8 , the positioning method of the present disclosure may include a CRI detection step of determining whether CRI has occurred and outputting a CRI resultant value (S1310). For example, the positioning device may determine whether CRI is generated by using magnitude information of a received signal received by a receiver. For example, when inter-signal interference occurs, the positioning device may detect CRI using a phenomenon in which the magnitude of a signal increases or decreases according to the phases of two pulse signals. At this time, magnitude information of the received signal may be obtained by calculating two correlation values of the in-phase and quadrature-phase of the signal as an RMS value.

As another example, the positioning device calculates a standard score (Z-value) using the average and standard deviation of the magnitude included in the magnitude information of the received signal, and determines whether the CRI occurs from the standard score calculated using the reference value. can do. For example, the positioning device may calculate an average and a standard deviation of received signal amplitudes using measured values of received signal amplitudes collected during a certain period of time. In addition, the positioning device may convert the average and standard deviation of the calculated received signal magnitude into standard scores (Z-values). Here, the standard score (Z-value) may be an indicator of how much the currently measured received signal level is positioned in a signal level distribution. Accordingly, the positioning device may predict that CRI has occurred when the converted standard score corresponds to a reference value or higher.

As another example, the positioning device may output a CRI result value according to a CRI determination result. For example, the positioning device may output CRI result values as 0 and 1 according to the CRI determination result. For example, the positioning device may determine that CRI has occurred when the calculated standard score corresponds to a reference value or higher, and output a CRI result value of 0 when it is determined that CRI has occurred. On the other hand, the positioning device may determine that CRI is not generated when the calculated standard score is less than the reference value, and output a CRI result value of 1 when it is determined that CRI is not generated. The CRI result value can be used to determine whether to use the loop filter output value of pulse signal tracking or to determine the weight of the TOA measurement value.

The positioning method may include a signal prediction step of predicting a predicted arrival time of a signal (S1320). For example, the positioning device may convert the phase measurement value calculated from the reference output signal and the received signal into an arrival time error using the CRI result value. For example, the positioning device may obtain a phase difference using an in-phase correlation value and a quadrature-phase correlation value of a reference output signal and a received signal. Also, the positioning device may calculate a phase measurement value from which noise is removed by using a loop filter from the acquired phase difference. For example, when the positioning device inputs a digital signal sample for about 250us from the expected arrival time of the pulse signal, which is the received signal, to the correlator, the phase difference between the 100kHz carrier, which is the reference output signal, and the input pulse signal can be obtained. can In addition, the obtained phase difference may pass through a loop filter to calculate a phase measurement value in which measurement noise is alleviated.

As another example, the positioning device may predict the predicted arrival time of the signal using the arrival time error. For example, the positioning device may determine whether to convert the arrival time error using a value obtained by multiplying the CRI result value and the phase measurement value, and convert the arrival time error into an arrival time error. In addition, the positioning device may predict the predicted arrival time by using the converted arrival time error, the current arrival time and the pulse period of the received signal. For example, if the positioning device determines that CRI is not generated and outputs a CRI result value as 1, the loop filter output may not be affected. On the other hand, if the positioning device determines that CRI is generated and outputs the CRI result value as 0, the loop filter output value becomes 0 and does not affect the next value, so that the CRI blanking effect can be obtained.

The positioning method may include a TOA estimation step of estimating a TOA estimation value (S1330). For example, the positioning device may calculate an estimated parameter using a time of arrival (TOA) measurement value and a pulse period of a received signal. For example, the positioning device may calculate a TOA measurement value using a pulse period from a current arrival time and an arrival time error, and calculate an estimated parameter by modeling the TOA measurement value. For example, the positioning device may compensate for the current pulse arrival time with an arrival time error and obtain the TOA measurement value with a remainder obtained by dividing the current pulse arrival time by the pulse period. Here, since the TOA measurement value can be acquired once per pulse, it may be about 10 to 20 per second. For another example, the positioning device can be modeled as a linear function because the calculated TOA measurement value increases or decreases with time, and since the measurement time has a pulse period interval, an estimation parameter from an equation modeled using a pulse period can be calculated. Here, the calculated estimated parameter may include a parameter meaning a change amount of the TOA measurement value and a parameter meaning a bias.

As another example, if there are N (N is a natural number of 2 or more) or more TOA measurement values, the positioning device may calculate the estimated parameters through the least squares method. For example, the positioning device may calculate an estimated parameter by applying a weight matrix to a measurement vector generated using N (N is a natural number of 2 or more) or more TOA measurement values and a measurement time matrix generated using a pulse period. there is. In addition, the positioning device may generate a weight matrix in the form of a diagonal matrix using CRI result values corresponding to the TOA measurement values. The generated weight matrix is subject to CRI, so if the CRI result value is 0, the effect of being excluded from the least squares method can be obtained.

As another example, the positioning device may estimate the TOA estimate value of the predicted arrival time using the calculated estimation parameter. For example, the positioning device may estimate a TOA estimate value of a predicted arrival time suitable for a desired measurement period using the calculated estimation parameter.

As described above, according to the present disclosure, a positioning device and method can be provided. In particular, it is possible to provide a positioning device and method capable of estimating an accurate position by estimating a precise TOA value from which the CRI effect is removed. In addition, a positioning device and method capable of improving TOA measurement performance can be provided by considering Doppler and oscillator frequency errors through linear function modeling and the least squares method.

The above description is merely illustrative of the technical idea of the present disclosure, and various modifications and variations can be made to those skilled in the art without departing from the essential characteristics of the technical idea. In addition, the present embodiments are not intended to limit the technical idea of the present disclosure, but rather to explain the scope of the present technical idea by these embodiments. The scope of protection of the present disclosure should be construed by the following claims, and all technical ideas within the scope equivalent thereto should be construed as being included in the scope of rights of the present disclosure.

Claims (16)

a CRI detection unit that determines whether cross-rate interference (CRI) has occurred by using magnitude information of a received signal received by the receiver and outputs a CRI resultant value according to the determination result;
a signal prediction unit for converting a phase measurement value calculated from the reference output signal and the received signal into an arrival time error using the CRI result value, and predicting a predicted arrival time of the signal using the arrival time error; and
and a TOA estimator calculating an estimation parameter using a time of arrival (TOA) measurement value and a pulse period of the received signal, and estimating a TOA estimation value of the predicted arrival time using the estimation parameter. Device. According to claim 1,
The CRI detection unit,
Positioning characterized in that a standard score (Z-value) is calculated using the average and standard deviation of the magnitude included in the magnitude information of the received signal, and whether the CRI occurs or not is determined from the standard score using a reference value Device. According to claim 2,
The CRI detection unit,
If the standard score corresponds to the reference value or more, it is determined that the CRI has occurred and the CRI result value is output as 0;
Wherein the positioning device determines that the CRI is not generated when the standard score is less than the reference value and outputs the CRI result value as 1. According to claim 1,
The signal prediction unit,
Obtaining a phase difference using an in-phase correlation value and a quadrature-phase correlation value of the reference output signal and the received signal during a specific time, and calculating the phase measurement value from which noise is removed using a loop filter from the phase difference Positioning device characterized in that. According to claim 1,
The signal prediction unit,
It is determined whether or not to convert the arrival time error by using a value obtained by multiplying the CRI result value by the phase measurement value, and using the current arrival time and the pulse period to determine whether or not to convert the arrival time error according to the decision, the predicted arrival time Positioning device characterized in that for predicting. According to claim 1,
The TOA estimation unit,
The positioning device according to claim 1 , wherein the TOA measurement value is calculated using the pulse period from the current arrival time and the arrival time error, and the estimation parameter is calculated by modeling the TOA measurement value. According to claim 1,
The TOA estimation unit,
Positioning characterized in that the estimation parameter is calculated by applying a weight matrix to a measurement vector generated using N (N is a natural number of 2 or more) or more TOA measurement values and a measurement time matrix generated using the pulse period. Device. According to claim 7,
The weight matrix,
The positioning device characterized in that it is generated in the form of a diagonal matrix using the CRI result value corresponding to the TOA measurement value. A CRI detection step of determining whether cross-rate interference (CRI) occurs using information on the magnitude of a received signal received by a receiver and outputting a CRI resultant value according to the determination result;
a signal prediction step of converting a phase measurement value calculated from a reference output signal and the received signal into an arrival time error using the CRI result value, and predicting a predicted arrival time of the signal using the arrival time error; and
A TOA estimation step of calculating an estimation parameter using a time of arrival (TOA) measurement value and a pulse period of the received signal, and estimating a TOA estimation value of the predicted arrival time using the estimation parameter. positioning method. According to claim 9,
The CRI detection step,
Positioning characterized in that a standard score (Z-value) is calculated using the average and standard deviation of the magnitude included in the magnitude information of the received signal, and whether the CRI occurs or not is determined from the standard score using a reference value Way. According to claim 10,
The CRI detection step,
If the standard score corresponds to the reference value or more, it is determined that the CRI has occurred and the CRI result value is output as 0;
and determining that the CRI is not generated when the standard score is less than the reference value and outputting the CRI resultant value as 1. According to claim 9,
The signal prediction step,
Obtaining a phase difference using an in-phase correlation value and a quadrature-phase correlation value of the reference output signal and the received signal during a specific time period, and calculating the phase measurement value from which noise is removed using a loop filter from the phase difference Positioning method characterized in that. According to claim 9,
The signal prediction step,
It is determined whether or not to convert the arrival time error by using a value obtained by multiplying the CRI result value by the phase measurement value, and using the current arrival time and the pulse period to determine whether or not to convert the arrival time error according to the decision, the predicted arrival time Positioning method characterized in that for predicting. According to claim 9,
The TOA estimation step,
and calculating the TOA measurement value using the pulse period from the current arrival time and the arrival time error, and calculating the estimated parameter by modeling the TOA measurement value. According to claim 9,
The TOA estimation step,
Positioning characterized in that the estimation parameter is calculated by applying a weight matrix to a measurement vector generated using N (N is a natural number of 2 or more) or more TOA measurement values and a measurement time matrix generated using the pulse period. Way. According to claim 15,
The weight matrix,
Characterized in that it is generated in the form of a diagonal matrix using the CRI result value corresponding to the TOA measurement value.

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