KR101576463B1 - Navigation signal tracking device and method for controlling the navigation signal tracking device - Google Patents

Abstract

The present invention relates to a navigation signal tracking device capable of tracking a navigation signal. According to an embodiment of the present invention, the navigation signal tracking device includes: a reception device for receiving a navigation signal received through a multi-path; a discriminator for generating a reference signal and generating a discriminator signal by multiplying and integrating the generated reference signal by the navigation signal; and a tracking loop for tracking the navigation signal based on the discriminator signal. The discriminator includes: an asymmetric reference code generation module for generating an asymmetric reference code in the shape asymmetric with respect to an origin; and a delay reference code generation module for generating a delayed reference code which is delayed by a certain chip from the asymmetric reference code. The reference signal is generated by combining the asymmetric code with the delayed reference code.

Description

TECHNICAL FIELD [0001] The present invention relates to a navigation signal tracking apparatus and a control method thereof, and more particularly,

The present invention relates to a navigation signal tracking apparatus capable of tracking a navigation signal.

The navigation signal is a signal used to measure the position, velocity or time of an antibody in the Global Navigation Satellite System (GNSS) and pseudolite or pseudo-satellite. Here, the Global Navigation Satellite System is a system that receives a navigation signal transmitted from a navigation satellite operated in a specific orbit through a receiver (for example, an antenna) of a navigation signal tracking device, It is a system configured to calculate navigation information such as position, speed, and time.

According to the satellite navigation system, navigation can be carried out regardless of weather conditions regardless of the world, and the amount of usage is continuously increasing due to the advantage of not accumulating errors. Typical receivers of a navigation signal tracking device include Global Positioning System (GPS) receiver and Global Navigation Satellite System (GNSS) receiver.

The navigation signal tracking device may be provided in an antibody or in a place other than the antibody (for example, a control tower, etc.). On the other hand, the navigation signal is received through a multipath due to an external factor around the navigation signal tracking device, thereby causing an error.

The cause of the reception through the multipath is reflection by an object (e.g., building) in the vicinity of the receiver of the navigation device.

That is, in addition to the navigation signal directly received from the transmitter to the receiver, the navigation signal tracking device generates a navigation signal (hereinafter referred to as a 'multipath signal' or a 'multi-path input signal' There is a problem that the accuracy of the tracking of the navigation signal is degraded due to the error.

There are many methods for removing multipath errors that have been announced so far, including antenna pattern design techniques, estimation techniques using ML (Maximum Likelihood) or Kalman filter, and a new structure using a correlator. Antenna pattern design scheme is a method of blocking the multipath signal by adjusting the reception pattern of the antenna. However, it has a disadvantage in that it can degrade the portability of the receiver although the error cancellation performance is very effective. The estimation method is a method of reducing the influence of multipath signals by estimating the size, phase, and delay time of the multipath signals using the measured correlation values. This method is superior to other methods in terms of multipath error elimination performance, but requires a lot of hardware and software, and has a disadvantage that it is difficult to implement in real time. The method using the new structure correlator eliminates the multipath error by changing the structure of the signal tracking loop and its performance is mostly determined according to the phase discriminator structure of the code tracking loop. This method is known to be the most suitable method to apply to real - time navigation because it is simple to implement hardware and software and has low computational complexity.

The methods using the new structured correlator are mostly based on narrowband correlators. Narrow band correlators have excellent multi - path error rejection performance, but have a narrow signal tracking range and are likely to fail to follow the signal in the high - voltage antibody and are difficult to perform signal acquisition alone.

In addition, Japanese Laid-Open Patent Application No. 10-2010-0023708 discloses a method of eliminating multipath errors by fixing the time difference between Early correlator and late correlator to 1 to 2 chip and tracking the minimum point of the output value difference.

However, in the above-mentioned publication, it is necessary not only to provide a separate configuration (minimum point tracker 4) necessary for tracking the minimum point of the Early-late correlator output value difference, but also to perform a large number of operations There is a limit to perform.

It is an object of the present invention to provide a navigation signal tracking apparatus and a control method thereof that can reduce an error of a navigation signal received through a multipath.

It is another object of the present invention to provide a navigation signal tracking device capable of increasing a range of a discriminator signal used for controlling a reference signal and tracking a navigation signal, and a control method thereof.

A navigation signal tracking device according to an embodiment of the present invention includes a receiver for receiving a navigation signal received through a multipath, a reference signal generator for multiplying the generated reference signal by the navigation signal, An asymmetric reference code generation module for generating an asymmetric reference code having an asymmetrical shape with respect to an origin, and an asymmetric reference code generation module for generating an asymmetric reference code based on the asymmetric reference code, And a delay reference code generation module for generating a delay reference code delayed by a certain chip from the reference code, wherein the reference signal is generated by combining the asymmetric reference code and the delay reference code.

In the embodiment, the operation range of the discriminator signal is increased by the delay reference code.

In an embodiment, the error of the navigation signal, which is additionally sensed as the operation range of the discriminator signal increases, is reduced based on the decrease of the amplitude of the delay reference code.

In an embodiment, the discriminator is characterized by reducing the pulse width of the asymmetric reference code to reduce the error of the navigation signal received through the multipath.

A method of controlling a navigation signal tracking device according to an embodiment of the present invention includes receiving a navigation signal received through a multipath, generating an asymmetric reference code having an asymmetrical shape with respect to an origin, Generating a reference signal by synthesizing the asymmetric reference code and the delay reference code, multiplying the generated reference signal by the navigation signal and integrating the reference signal, Generating a signal and tracking the navigation signal based on the discriminator signal.

In the embodiment, the operation range of the discriminator signal is increased by the delay reference code.

The present invention can reduce an error of a navigation signal received through a multipath using an asymmetric reference code and a delay reference code. Therefore, the present invention can reduce the error of the navigation signal received through the multipath simply by controlling only the reference signal composed of the asymmetric reference code and the delay reference code.

The present invention can increase the operation range of the discriminator signal used to track the navigation signal by controlling the reference signal. Therefore, even when the antibody is high dynamic, the possibility of missing the navigation signal can be lowered by using the navigation signal receiving apparatus with an increased operational range.

1 is a conceptual diagram illustrating a satellite navigation system according to an embodiment of the present invention.
2 is a block diagram illustrating a configuration of a navigation signal tracking device according to an embodiment of the present invention.
3 is a conceptual diagram for explaining a method of tracking a navigation signal using a discriminator signal output using a standard correlator and the discriminator signal output.
4A and 4B are conceptual diagrams illustrating a method of reducing a multipath error using a conventional symmetric reference signal.
5 is a conceptual diagram illustrating an asymmetric reference code according to an embodiment of the present invention.
6 is a conceptual diagram illustrating a discriminator signal and a multipath error output using an asymmetric reference code according to an embodiment of the present invention.
7 is a conceptual diagram for explaining a delay reference code according to an embodiment of the present invention.
8 is a conceptual diagram for explaining a reference signal in which an asymmetric reference code and a delay reference code are combined according to an embodiment of the present invention.
9 is a conceptual diagram illustrating a discriminator signal and a multipath error output using a reference signal according to an embodiment of the present invention.
10A and 10B are conceptual diagrams for explaining a method of reducing a multipath error by controlling a reference signal according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, wherein like reference numerals are used to designate identical or similar elements, and redundant description thereof will be omitted. The suffix "module" and " part "for the components used in the following description are given or mixed in consideration of ease of specification, and do not have their own meaning or role. In the following description of the embodiments of the present invention, a detailed description of related arts will be omitted when it is determined that the gist of the embodiments disclosed herein may be blurred. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed. , ≪ / RTI > equivalents, and alternatives.

1 is a conceptual diagram illustrating a satellite navigation system according to an embodiment of the present invention.

Referring to FIG. 1, a Global Navigation Satellite System (GNSS) according to an embodiment of the present invention may include a navigation signal tracking device 100, an antibody 200, and a satellite 300 .

The antibody 200 may include any means capable of moving, and may include, for example, an automobile, a mobile terminal, an aircraft, a ship, and the like.

The satellite 300 may transmit a navigation signal 500 containing information related to its position to the navigation signal tracking device 100. When the satellite 300 receives information related to the position of the antibody 200 from the antibody 200, the satellite 300 transmits a signal 500 including information related to the position of the antibody 200 to the navigation signal tracking device 100).

The navigation signal tracking device 100 receives the navigation signal 500 from the satellite 300 and generates a navigation signal 500 based on the received navigation signal 500 to generate the navigation signal 500 such as the position, The included navigation information can be analyzed.

The navigation signal tracking apparatus 100 may be provided in the antibody 200 or may be provided in a place other than the antibody (for example, a control tower, etc.).

Meanwhile, the navigation signal 500 may be transmitted from the satellite 300 to the navigation signal tracking device 100 through a multipath. Specifically, the navigation signal tracking device 100 can receive the navigation signals 500a and 500b received from the satellite 300 through a multipath.

The navigation signal tracking apparatus 100 includes a navigation signal 500a (a direct wave or a navigation signal received from a visible direction, hereinafter referred to as an 'input signal 500a') directly received from the satellite 300 and an external object 400 (Hereinafter, referred to as a 'multipath input signal 500b') that is reflected by the input / output terminal 500a. That is, even if one of the navigation signals 500 is transmitted from the satellite 300, the receiving side (the navigation signal tracking device 100) transmits the navigation signal 500 (at least two multipaths) 500a, and 500b.

Accordingly, an error occurs in the tracking of the navigation signal in the navigation signal tracking device (100).

Hereinafter, referring to FIG. 2, a detailed description will be made of a navigation signal tracking device capable of reducing an error of a navigation signal coming through a multipath according to an embodiment of the present invention.

2 is a block diagram illustrating a configuration of a navigation signal tracking device according to an embodiment of the present invention.

The navigation signal tracking device 100 may include a receiver 110, a discriminator 150 and a tracking loop 160.

The receiver 110 may receive a navigation signal transmitted from the satellite 300. The navigation signals 500a and 500b received through the receiver 110 may be transmitted to the discriminator 150. [

The discriminator 150 may generate a discriminator signal 700 that is an indicator of the difference between the navigation signals 500a and 500b received through the receiver 110. [ The discriminator 150 may include a reference signal generator 120, a multiplier 130, and an integrator 140. The discriminator 150 may serve as a correlator.

The tracking loop 160 may track the navigation signal 500 based on the discriminator signal 700 generated by the discriminator 150.

Hereinafter, a conventional standard correlator, a Narrow Correlator, and a High Resolution Correlator (HRC) will be described to describe the discriminator 150 according to an embodiment of the present invention.

3 is a conceptual diagram for explaining a method of tracking a navigation signal using a discriminator signal outputted using a standard correlator and the discriminator signal outputted,

4A and 4B are conceptual diagrams illustrating a method of reducing a multipath error using a conventional symmetric reference signal.

The correlator can multiply the input signal by the replica signal generated by the code generator (corresponding to the reference code generator) and integrate it. That is, the correlator output value R (?) Means a value obtained by integrating the product of the input signal x (t) (the navigation signal) and the replica signal r (t).

Equation (1) can be termed an autocorrelation function. Equation (1) has the maximum value because the difference between the two signals, that is, when the code phase difference between the input signal and the replica signal is exactly the same (eg, τ = 0), is multiplied by the same two signals. Becomes smaller.

Meanwhile, in order to construct a DLL (Delay Locked Loop) for signal tracking, an EML (Early-Minus-Late) correlator is basically constructed by modifying Equation (1).

The EML correlator includes an early correlator that generates a replica signal as fast as d / 2 than the replica signal r (t) of Equation 1 and a replica signal r (t) that is slower by d / 2 than the replica signal r Lt; RTI ID = 0.0 > Late correlator < / RTI >

The EML correlator output value D (tau) means a value obtained by subtracting the late correlator output value of the input signal x (t) from the early correlator output value with respect to the input signal x (t) Can be defined as follows.

Here d is called Chip-Spacing and is called standard correlator when d = 1 chip.

The EML correlator output value D (?) May be the same as the graph shown by the solid line in the graph shown in FIG. 3.

When the difference between the two signals is τ = 0, the output of the standard correlator becomes 0. As the error becomes larger, the output value of the EML correlator output (D (τ)) becomes larger. Therefore, in the DLL, this value is used as a discriminator signal which is an index indicating the difference between the input value and the estimated value. In the present invention, the error of the input signal is judged such as the EML correlator output value D Is defined as a discriminator signal 700 (D (?)).

Equation (2) can be expressed as Equation (3).

As shown in Equation (3), the discriminator signal 700 generated by the discriminator 150 is a correlation value between the input signal x (t) and the signal y (t) generated by the reference signal generator 120 .

In the present specification, r (t) and y (t) in Equations (1) and (3) are referred to as reference signals.

Meanwhile, when the navigation signal 500 is received through the multipath, the receiver 110 can receive the direct wave 500a and the multipath signal 500b. In this case, assuming that a multipath or indirect signal 500b is input, the input signal x (t) is expressed by Equation (4). Subscripts d and I represent direct signals (direct wave, input signal 500a) and indirect signals (multipath input signal 500b), respectively.

When the input signal is equal to Equation (4), the discriminator 150 can output the discriminator signal D (?) 700 according to Equation (5).

A solid line in the graph shown in FIG. 3 is a discriminator signal when there is no multipath signal in the input signal, and a dotted line is a discriminator signal when a multipath signal delayed by a predetermined magnitude is included in the input signal.

The tracking loop 160 tracks the point at which the discriminator output becomes zero in the discriminator signal. Therefore, when there is no multipath input signal 500b in the navigation signal 500, the O1 value is tracked. At this time, the time difference between the navigation signal and the replica signal (reference signal) is τ = 0. Therefore, the navigation signal can be tracked accurately.

On the other hand, if there is a multi-path input signal 500b in the navigation signal 500, the tracking loop 160 follows O2, so that τ> 0. That is, the reference signal 600 has a bias of a predetermined magnitude with respect to the input signal, which is referred to as a multipath error, and is reflected in a distance error from the transmitter to the receiver.

The maximum magnitude of the multipath error (e.g., the distance from O2 to the origin) of all the delay values of the multipath input signal 500b based on the input signal 500a is as shown in the lower graph of FIG.

On the other hand, representative conventional technologies used to reduce multipath errors are Narrow Correlator and HRC (High Resolution Correlator). The narrow-band correlator reduces the value of Chip-Spacing (d) to less than 1 when constructing the discriminator using Equation (3).

For example, setting d = 0.1 in Equation 3 reduces the maximum discriminator signal size and reduces the pull-in range by decreasing d.

That is, when the amplitude of the discriminator signal 700 is reduced by changing the reference signal 600, the magnitude of the maximum multipath error is reduced and the operation range (Pull-in Range) of the discriminator, that is, (S-curve), it is possible to reduce the range of the signal delay value (Delay) causing the multi-path error.

A new method of defining a reference signal using this principle has been proposed, and a typical method is a high resolution correlator (HRC) technique. Is defined as Equation (6) using a linear combination of narrow-band correlators with different d values.

The output result of the high-resolution correlator for the input signal (navigation signal) is shown in Figs. 4A and 4B.

The graph shown above the graph of FIG. 4A shows the input signal 500a, and the graph shown at the bottom of FIG. 4A shows the reference signal 600 generated in the high-resolution correlator. The high-resolution correlator can form a pulse, that is, a symmetric reference signal, both of which are symmetric if there is a bit-conversion of the input signal x (t).

The graph shown in the upper part of FIG. 4B shows the discriminator signal 700 output from the high-resolution correlator. That is, the discriminator 150 multiplies the input signal x (t) shown in FIG. 4A by the reference signal y (t) of the high resolution correlator HRC shown in FIG. It is possible to output the discriminator signal D (?) 700 as shown.

Meanwhile, if the multi-path input signal 500b is included in the navigation signal 500 received by the high resolution correlator (HRC), the discriminator signal can be generated for the multi-path input signal 500b as described above.

The graph shown at the bottom of FIG. 4B shows that when the high-resolution correlator is used, the tracking loop 160 uses the discriminator signal generated by the input signal 500a and the discriminator signal generated by the multipath input signal 500b And the multi-path error estimated by the above method.

For example, if the high resolution correlator (HRC) is set to d1 = 0.1 and d2 = 0.2 in Equation 6, the output of the discriminator signal 700 for the input signal 500a detected using Equation (6) 4b. ≪ / RTI > Similarly, a discriminator signal is generated for the multi-path input signal 500b and the discriminator signal for the input signal 500a and the multi-path input signal 500b is used to generate all the multi- The distance error due to the maximum multipath is shown in the graph shown at the bottom of FIG. 4B.

When a high-resolution correlator is used, the discriminator signal of the high-resolution correlator has a smaller amplitude than that of the discriminator signal output from the narrow-band correlator. Therefore, the multipath distance error magnitude of the high- It can be confirmed that it is somewhat smaller than the size.

However, since the operating range 710 of the discriminator signal output through the high-resolution correlator is narrower than the operating range of the discriminator signal output through the narrow-band correlator, as shown above in FIG. 4B, Path error delay size (Delay) of FIG. 3B is smaller than the multi-path error delay size (Delay) shown in FIG. 3B. That is, the narrow-band correlator can respond to a signal with a delay value of about 100 m, while the high-resolution correlator (HRC) responds only to signals with a delay value within a few tens of meters.

That is, if the operating range 710 of the discriminator signal 700 is narrow, as shown above in FIG. 4B, the tracking loop 160 may miss the navigation signal. For example, if the difference between the input signal delay value estimated by the tracking loop 160 and the signal delay value of the multipath input signal due to abrupt start of the antibody is about 0.2 chips, the output value of the discriminator signal 700 This value can not be represented by zero value. Therefore, the receiver signal tracking loop may miss the signal.

Hereinafter, a method of reducing the multipath distance error magnitude while increasing the operation range 700 of the discriminator signal 700 will be described in more detail with reference to the accompanying drawings.

FIG. 5 is a conceptual diagram for explaining an asymmetric reference code according to an embodiment of the present invention. FIG. 6 is a diagram illustrating a discriminator signal and a multipath error output using an asymmetric reference code according to an exemplary embodiment of the present invention. Fig.

The reference signal y (t) of the standard correlator, the narrow-band correlator and the high-resolution correlator described in Figs. 3 to 4B is called a symmetric reference signal since both are symmetric with respect to the origin as shown in the lower portion of Fig. 4A .

Meanwhile, in the present invention, characteristics different from those of the high resolution correlator (HRC) can be obtained when the shape of the reference signal 600 is asymmetric with respect to the origin on the left and right sides.

That is, the reference signal generator 120 of the present invention may include an asymmetric reference code generation module 122. The asymmetric reference code generation module 122 may generate an asymmetric reference code 610 having an asymmetric shape with respect to the origin.

The asymmetric reference code generated by the asymmetric reference code generation module 122 may be the same as the graph shown in the lower part of FIG. The graph shown in the upper part of FIG. 5 shows an example of the input signal 500a.

5, the reference signal (asymmetric reference code) generated by the asymmetric reference code generation module 122 may include a pulse having a left-right asymmetry with respect to the origin.

The pulse may be generated when there is bit conversion of the input signal x (t) (navigation signal), or may be generated with a certain period. The asymmetric pulse included in the asymmetric reference code may have a phase of 180 degrees converted based on the bit conversion of the input signal.

The discriminator 150 may multiply the navigation signal 500 corresponding to the input signal x (t) by the asymmetric reference code 610 (130) and integrate 140 to generate the discriminator signal 700 , And the generated discriminator signal 700 may be the same as the graph shown in the upper part of FIG. Also, when only the asymmetric reference code 610 is used, the multipath error may be the same as the graph shown in the lower part of FIG.

6, it can be seen that the operating range 710 of the discriminator signal 700 using the asymmetric reference code 610 is larger than the operating range of the discriminator signal of the high-resolution correlator have. Thus, even if the multi-path error of the navigation signal 500 is increased due to high dynamic or external interference of the antibody, the tracking loop 160 is more robust than when using a high resolution correlator (when using a symmetric reference code The probability of missing the navigation signal 500 including the multi-path input signal is reduced.

6, by using the asymmetric reference code 610, the discriminator 150 can determine the operating range (for example, the range of the operating range) by using the high-resolution correlator 710) can be increased.

6, since the operation range of the discriminator signal 700 in the negative direction with respect to the origin is still narrow in the operation range 710 of the discriminator signal 700, the tracking loop 160 outputs the navigation signal < RTI ID = (500) is delayed in the negative direction (-), the navigation signal may be missed.

In case of using the asymmetric reference code, the multipath error has a performance error similar to that of the high-resolution correlator for signals reflected within a few tens of meters. However, unlike the high-resolution correlator, Do not.

Hereinafter, a method of further increasing the operation range of the discriminator signal will be described more specifically with reference to the accompanying drawings.

FIG. 7 is a conceptual diagram for explaining a delay reference code according to an embodiment of the present invention. FIG. 8 is a conceptual diagram for explaining a reference signal in which an asymmetric reference code and a delay reference code are combined according to an embodiment of the present invention. to be. 9 is a conceptual diagram illustrating a discriminator signal and a multipath error output using a reference signal according to an embodiment of the present invention.

The reference signal generator 120 of the navigation signal tracking apparatus 100 of the present invention includes an asymmetric reference code generation module 122 and may further include a delay reference code generation module 124.

The delay reference code generation module 124 may generate a delay reference code 620 delayed by a certain chip from the asymmetric reference code 610. The generated delay reference code 620 may be generated as shown in FIGS. Can be the same.

The reference signal generator 120 synthesizes the asymmetric reference code 610 generated by the asymmetric reference code generating module 122 and the delay reference code 620 generated by the delay reference code generating module 124, (T) 600, and the generated reference signal y (t) may be the same as the graph shown in the lower portion of FIG.

For example, the delay reference code generation module may generate a delay reference code 620 such that a pulse 624 is generated at a point delayed by a half chip or 90 degrees from the pulse included in the asymmetric reference code have.

8, the delay reference code generation module 124 changes the phase of the pulse included in the delay reference code by 180 degrees based on the bit conversion of the input signal x (t) (the navigation signal) .

The discriminator 150 may multiply the reference signal 600 in which the asymmetric reference code 610 and the delay reference code 620 are combined with the navigation signal 500 and integrate them to generate the discriminator signal 700 have.

The discriminator signal 700 may be the same as the graph shown in the upper part of FIG.

Referring to FIG. 9, it can be seen that the operating range 730 of the discriminator signal 700 is increased 720 from the discriminator signal operating range 710 generated according to the asymmetric reference code. That is, the operating range 730 of the discriminator signal may be increased by the delay reference code 620. [

At this time, a multipath error with respect to a delay value of all the multipath signals received through the receiver 110 is the same as the graph shown in the lower part of FIG. 9, when the reference signal 600 in which the delay reference code 620 is synthesized with the asymmetric reference code 610 is used, it is confirmed that the operation range of the discriminator signal 700 is increased to the left side .

This means that it has become more robust against the sudden start of the antibody (the sudden start of the navigation signal tracking device when the navigation signal tracking device is attached to the antibody).

Referring to the graph shown in the lower part of FIG. 9, the multi-path error has a delay value of several tens to hundreds of m, while maintaining the performance within the reference range, compared with the case using only the asymmetric reference code The multi-path error 900 can be detected. However, at this time, the multi-path error 900 for the delay value of several tens to hundreds of m is smaller than the maximum multi-path error, so that the tracking loop 160 does not greatly influence the tracking of the navigation signal. Rather, detecting multipath errors for delay values from a few tens of meters to a hundred meters means that the likelihood of missed navigation signals is reduced even for sudden maneuvering of the antibody or sudden maneuvering of the navigation signal tracker.

Hereinafter, a method for reducing multipath errors will be described in more detail with reference to the accompanying drawings.

10A and 10B are conceptual diagrams for explaining a method of reducing a multipath error by controlling a reference signal according to an embodiment of the present invention.

9, the present invention generates a reference signal 600 by synthesizing a delay reference code 620 with an asymmetric reference code 610, and generates a discriminator signal 600 using the generated reference signal 600 700 can be increased.

Meanwhile, as the operation range 730 of the discriminator signal 700 is increased, a range error 900 for the delay value (Delay) of the multipath error is further generated.

The error 900 of the navigation signal that is additionally sensed as the operating range 730 of the discriminator signal 700 is increased may be reduced based on the decrease in the amplitude 624 of the delay reference code.

10A is a multipath error when the reference signal 600 including the delay reference code having the amplitude of the first magnitude is used, and the graph shown at the lower side of FIG. Is a multipath error when a reference signal 600 including a delay reference code having a small amplitude of a second magnitude is used.

When the delay reference code having the amplitude of the first magnitude is used, an error (distance error) 910a of the navigation signal that is additionally sensed as the discriminator signal's operating range increases is smaller than the second magnitude When the delay reference code having the amplitude is used, it can be seen that as the operation range of the discriminator signal increases, it is larger than the error 910b of the additionally detected navigation signal.

That is, the discriminator 150 reduces the amplitude 624 of the pulse included in the delay reference code 620, and increases the magnitude of the error of the additionally sensed navigation signal as the operation range of the discriminator signal increases from 910a to 910b Can be reduced.

Meanwhile, the discriminator 150 can reduce the maximum error (maximum distance error) of the navigation signal by controlling the pulse width 614 of the asymmetric reference code 610. The pulse width 614 may include at least one of a portion having a larger width and a portion having a smaller width among the asymmetrical types of pulses included in the asymmetric reference code, as shown in Fig. 5 (b).

10B is a multipath maximum error when a reference signal 600 including an asymmetric reference code having a pulse width of a first magnitude is used, and the graph shown at the lower part of FIG. And a reference signal 600 including an asymmetric reference code having a pulse width of a second magnitude smaller than the magnitude of the reference signal.

A distance error 920a of the navigation signal in the case of using an asymmetric reference code having a pulse width of the first magnitude is obtained as an error of the navigation signal in the case of using an asymmetric reference code having a pulse width of a second size smaller than the first size (920b).

That is, the discriminator 150 reduces the pulse width 614 of the asymmetric reference code 610 included in the reference signal 600 to reduce the error (maximum distance error) of the navigation signal received through the multipath have.

The discriminator 150 is controlled by a control unit (not shown) included in the navigation signal tracking apparatus 100 or by an asymmetric reference code generation module 122 and a delay reference code generation module 124, To control the pulse width 614 of the asymmetric reference code or to control the amplitude 624 of the delay reference code.

That is, the discriminator 150 adjusts the magnitude of the multipath error by adjusting the pulse width of the asymmetric reference code and the amplitude of the delay reference code according to the application requirements and the hardware conditions under the control of the controller.

The control method of the navigation signal tracking device as described above is as follows.

The navigation signal tracking device 100 according to an embodiment of the present invention can receive the navigation signals 500a and 500b received through the multi-path through the receiver 110. [

The asymmetric reference code generation module 122 included in the reference signal generation unit 120 of the navigation signal tracking apparatus 100 may generate an asymmetric reference code having an asymmetric shape with respect to the origin.

The delay reference code generation module 122 included in the reference signal generation unit 120 of the navigation signal tracking device 100 may generate a delay reference code delayed by a certain chip from the asymmetric reference code.

The reference signal generator 120 of the navigation signal tracking device 100 may generate a reference signal by combining the asymmetric reference code and the delay reference code.

Then, the discriminator 150 may multiply the generated reference signal by the navigation signal and integrate it to generate a discriminator signal.

The tracking loop 160 may track the navigation signal based on the discriminator signal.

At this time, the discriminator 150 controls the asymmetric reference code generation module 122 and the delay reference code generation module 124 according to the control of the control unit so that the pulse width 614 of the asymmetric reference code and the amplitude 624 can be adjusted.

Thus, the navigation signal tracking device 100 can increase the operation range of the discriminator signal used for tracking the navigation signal. In addition, the navigation signal tracking device 100 can control the error (multipath error) of the navigation signal included in the navigation signal received through the multipath.

As described above, the present invention can reduce an error of a navigation signal received through a multipath using an asymmetric reference code and a delay reference code. Therefore, the present invention can reduce the error of the navigation signal received through the multipath simply by controlling only the reference signal composed of the asymmetric reference code and the delay reference code.

The present invention can increase the operation range of the discriminator signal used to track the navigation signal by controlling the reference signal. Therefore, even when the antibody is high dynamic, the possibility of missing the navigation signal can be lowered by using the navigation signal receiving apparatus with an increased operational range.

Claims (6)

A receiver for receiving a navigation signal received via multiple paths;
A discriminator for generating a discriminator signal by generating a reference signal, multiplying the generated reference signal by the navigation signal, and integrating the resultant signal; And
And a tracking loop for tracking the navigation signal based on the discriminator signal,
The discriminator includes:
An asymmetric reference code generation module for generating an asymmetric reference code having an asymmetric shape with respect to an origin; And
And a delay reference code generation module for generating a delay reference code delayed by a certain chip from the asymmetric reference code,
Wherein the reference signal is generated by combining the asymmetric reference code and the delay reference code.
The method according to claim 1,
The operation range of the discriminator signal is,
Wherein the delayed reference code is increased by the delay reference code.
3. The method of claim 2,
Wherein the error of the navigation signal additionally sensed as the discriminator signal's operating range is increased is reduced based on the decrease of the amplitude of the delay reference code.
The method according to claim 1,
The discriminator includes:
And decreasing the pulse width of the asymmetric reference code to reduce the error of the navigation signal received through the multipath.
A method of controlling a navigation signal tracking device,
Receiving a navigation signal received via a multipath;
Generating an asymmetric reference code having an asymmetric shape with respect to an origin;
Generating a delay reference code delayed by a certain chip from the asymmetric reference code;
Generating a reference signal by combining the asymmetric reference code and the delay reference code;
Multiplying the generated reference signal by the navigation signal and integrating the resultant signal to generate a discriminator signal; And
And tracking the navigation signal based on the discriminator signal.
6. The method of claim 5,
The operation range of the discriminator signal is,
Wherein the delayed reference code is increased by the delay reference code.

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