KR20110060734A - Apparatus and method for adaptive acquiring satellite navigation signal - Google Patents

Abstract

PURPOSE: An apparatus and a method for acquiring adaptive satellite navigation signals are provided to reduce time required for acquiring the satellite navigation signals and increase possibility for acquiring the satellite navigation signals. CONSTITUTION: A carrier wave eliminating part(300) converts inputted satellite navigation signal into a processable frequency band. An I/Q signal down sampling module(400) generates the correlation between an I/Q channel signal through the carrier wave eliminating part and a copy code signal generated from a receiving part. A code generator(500) generates the signal correlation with respect to the input signal which is down-sampled from the I/Q signal down sampling module. A code rate converting part(600) selects corresponding PRN according to inputted code amount codes generated from the code generator. A signal correlating part(700) generates the signal correlation of the down-sampled input signal and the copy code signal with the converted code rate.

Description

Adaptive navigation satellite signal acquisition device and method {APPARATUS AND METHOD FOR ADAPTIVE ACQUIRING SATELLITE NAVIGATION SIGNAL}

The present invention relates to an apparatus and a method for acquiring a navigation satellite signal received from a navigation satellite, and in particular, to increase the probability of signal acquisition success by variably using a navigation satellite signal used for acquisition of a navigation satellite signal according to a receiving environment. The present invention relates to an adaptive navigation satellite signal acquisition device and method that can shorten the signal acquisition time and improve the availability of satellite navigation services in a satellite navigation receiver.

In general, GPS (Global Positioning System), which provides positioning services using navigation satellites, is a US satellite navigation system originally developed for military operations, but is currently used for precision construction as well as geodetic and surveying as well as vehicle navigation. And precision agriculture.

GPS, the US satellite navigation system, consists of 32 satellites arranged on six orbits, and the number of satellites that make up the satellite seat is changed when the old satellites are discarded and replaced by new GPS II satellites. Since 1994, global service has been provided and current GPS II version satellites are involved. The latest satellite version is the GPS II-F satellite. Lockheed Martin is currently developing a GPS III program under a $ 1.4 billion development and production contract. As the first launch of the GPS III program, eight GPS III-A satellite launches are scheduled for 2014.

However, GPS in the United States is not the only satellite navigation system in the world, and Russia, Europe, China, India and Japan have their own satellite navigation systems or are under development. As a result, by 2013, as a Global Navigation Satellite System (GNSS), 131 satellites will provide at least 10 meters of accuracy to aircraft and other transportation equipment.

A brief overview of the satellite navigation systems currently in service or under development is the Russian satellite navigation system GLONASS, which consists of 24 satellites arranged on three orbital planes close to orbits with an inclination of about 64.8 degrees. GLONASS Phase 1 was completed in 1991 with seven satellites in two orbits 120 degrees apart from each other, twelve GLONASS satellites were added in 1993 and 94, 7 known as Uragan-M (or GLONASS-M). Second-generation satellites with a lifespan of two years were launched in 2001, 2004, and 2005, and there were 14 satellites in orbit at the end of 2005. The third generation of GLONASS satellites with a lifespan of 10-12 years, known as Uragan-K (or GLONASS-K), will be added to make up 24 satellite seats in 2012.

Beidu-2 (Compass), China's Beidu satellite navigation system, consists of a total of 35 satellites with five satellites placed on Earth's geostationary orbit and 30 satellites placed on Earth's mid-orbit. There is now Beidu-1, which consists of three satellites developed by the China Academy of Space Technology, which began providing navigation services in late 2001 and was also available to civilian users in 2004. Beidu-1 provides 10-meter accuracy of public service and more precise Chinese military service, and plans to launch 10 satellites by 2010, preparing the first step towards Beidu-2 global navigation performance.

India's Indian Regional Navigational Satellite System (IRNSSS) is a regional navigational satellite system, developed by the Indian Space Research Organization (ISRO), that has three satellites located on Earth's geostationary orbit and has a 29-degree tilt angle at the equator plane. Four satellites will be deployed in the global orbit. The Indian government approved the project in 2006 and hopes to complete a system of seven satellites in 2012.

Japan's Quasi-Zenith Satellite System (QZSS) consists of three satellites combined with enhanced GPS to provide geolocation services in Japan. QZSS's first satellite launch is scheduled for 2009. It is.

The Galileo navigation system, a European satellite navigation system, consists of 30 satellites arranged on three orbits with a 56-degree tilt angle at the equator. The first experimental satellite, GIOVE-A, was launched in December 2005. In 2008, GIOVE-B and GIOVE-A2 satellites were launched. In addition, additional satellites will be launched to verify the system-related infrastructure. Upon completion, the remaining satellites will be launched and the entire system will be fully operational in 2013.

In particular, the development of Galileo in Europe is a system that Korea also participates in, unlike the United States GPS, which was developed for military operation, has been developed for commercial use since the beginning. According to the European Commission's GNSS experts, GPS is a standard military system, but GPS and Galileo can be used together for better service. Although not all issues related to GPS and Galileo interoperability have been resolved, Europe and the United States signed a treaty in 2004 on the interoperability and compatibility of GPS and Galileo satellite navigation systems.

The development of global satellite navigation systems stems from military, political and commercial factors, especially in Europe's decision to build its own private GNSS network, if the US GPS breaks down for two days. Since it is dependent enough to lose more than this, it is trying to reduce the US dependence on GPS.

It is not clear whether satellite navigation systems in Europe, China, India and Japan will cooperate or compete with each other for the US GPS and the GLONASS network in Russia, but the cooperation of these networks will be more relevant to users. It is clear that it will provide sophisticated GNSS services.

In particular, GPS / Galileo networks that use the same Code Division Multiple Access (CDMA) scheme can provide users with accurate location information through information from satellites twice as large as existing satellites. In particular, it can make a big difference in improving the location information of complex urban areas. Market forecasters foresee that this improved service will lead to a big boom in the GNSS product and services market. The global market for precision GNSS products and services is expected to be between $ 6 billion and $ 8 billion by 2012. The US GPS Industry Council estimates that the global market for GPS equipment reached $ 15 billion in 2006 and is growing by 25-30% annually.

European Commission experts predict that the global market for satellite navigation products and services will reach $ 400 billion by 2025, with 3 billion satellite navigation receivers by 2020 and the Galileo program creating 150,000 jobs across Europe. I think it will. UK Dept. The 2007 study by of Transport estimates that the profits from the GNSS market industry to the UK will reach £ 14 billion by 2025. The European Union has set aside US $ 3.4 billion between 2007 and 2013 to develop the European Geostationary Navigation Overlay Service (EGNOS) and the Galileo system. Under the EC's program management, the European Space Agency ESA is in charge of acquisition and design. More accurate and robust GNSS geolocation systems will open up new applications in many markets, including engineering, aviation, agriculture, ships and marine.

GPS and Galileo There are many things that have not yet been determined how to operate these two systems together. For example, receiving a signal from GPS and verifying it through Galileo, or receiving both a signal from GPS and Galileo. However, the first stage of development of the 'Multiconstellation Receiver', which is based on a joint GPS / Galileo signal processor and receives signals from multi-water satellites, has already begun. Standards for these receivers are expected to be completed in 2011 or 2012, according to the Single European Sky ATM Research (SESAR) Program Timetable. Many industry groups are involved in developing high standards for GPS / Galileo integration. Most of the work is focused on cost and complexity issues.

Therefore, in order to activate satellite navigation service using satellite navigation system, there is an urgent need for a signal acquisition method to effectively utilize various types of navigation satellite signals transmitted by Galileo, Chinese compass, Japanese quasi-ceiling satellite system including conventional GPS. It is becoming.

Looking at the prior art related to the signal acquisition method required in the above-described GNSS network environment, Korean Patent Publication No. 2006-0093978 (published on Aug. 28, 2006, hereinafter referred to as 'Document 1'), "the fast signal of the GPS receiver Acquisition method and dual frequency correlator therefor "describes a dual frequency correlator that enables fast signal acquisition by reducing the number of frequency search grids to search for signal acquisition by applying a dual frequency correlator to a GPS receiver. have.

Looking at the contents of Document 1 in more detail, in a dual carrier correlator used for fast signal acquisition in a GPS receiver, a first carrier generator for generating a carrier signal having a first frequency and a second frequency A second carrier generator for generating a carrier signal, a first carrier mixer for multiplying the signals generated by the first carrier generator and the second carrier generator, and a correlator input signal input to a dual frequency correlator and an output signal of the first carrier mixer. A low pass that integrates the output signal of the code mixer and the code mixer for correlating the output signal of the second carrier mixer, the second carrier mixer to be multiplied with the codes (Early, Prompt, Lately) having a code phase difference at regular intervals during the line detection integration time. Fast using dual frequency correlator and dual frequency correlator with pass filter A signal acquisition method comprising: a fast signal acquisition method of a GPS receiver capable of fast signal acquisition by reducing the number of frequency search grids to be searched for signal acquisition by applying a dual frequency correlator to a GPS receiver, and a dual frequency correlator for the same The technique is described.

However, Document 1 does not provide a method of variably applying navigation satellite signals received from GPS and Galileo navigation satellites or related technologies, and thus, there is a problem in that a signal acquisition method required in a GNSS network environment cannot be provided. .

As another conventional technology, Korean Patent Publication No. 2006-0072595 (published on June 28, 2006, hereinafter referred to as 'Document 2'), "Initial Synchronization Method of GPS Receiver for Vehicle Navigation System Effective in Weak Signal Environment" Referring to Document 2, it relates to a conventional GPS initial synchronization method of a vehicle navigation system, and more particularly, to an initial synchronization method of a GPS receiver for smoothly acquiring a GPS satellite signal in a weak signal environment and outputting accurate vehicle position information.

An initial synchronization method of a GPS receiver for a vehicle navigation system according to Document 2 includes a first step of transmitting a converted GPS signal to a processable frequency band by converting a received GPS signal into a radio frequency baseband conversion, and the converted GPS signal and a sixth step A second step of outputting an output signal by checking a correlation state of the spread signal generated by the correlator; and a third step of outputting an output signal of the correlator as a scalar shape and outputting an initial synchronization result value; A fourth step of determining whether the initial synchronization is successful by comparing the value with a predetermined signal detection threshold, and if the failure is found in the fourth step, the pseudo-noise code phase and frequency which is a property of the spreading signal required in the second step A fifth step of determining information and a sixth step of generating a spreading signal using the information determined by the fifth step and delivering the spread signal to the correlator; An initial synchronization method of a GPS receiver for a vehicle navigation system comprising: a first synchronous accumulation of an output signal of the correlator; a differential detection of a first synchronous accumulation value; Is obtained, and a scalarized initial synchronization result value is output by accumulating the square root of the second synchronization.

As described above, the initial synchronization method of the GPS receiver for the vehicle navigation system of document 2 can receive more GPS satellites than the conventional method by overcoming the GPS signal weakening caused by mounting inside the vehicle rig. Receiving GPS satellites can be expected to improve the positioning accuracy of the GPS receiver. In addition, the weak signal environment can be overcome, allowing the design to determine the position of the GPS receiver for the vehicle navigation system more freely. In addition, in a weak signal environment, GPS satellites can be acquired faster than the conventional method for fast positioning.

However, even in the case of Document 2, although the GPS satellite signal may be smoothly acquired in the weak signal environment of the vehicle navigation system and the initial synchronization method of the GPS receiver may be provided to output accurate vehicle location information, the weak signal environment of the GNSS network may be provided. In order to efficiently acquire navigation satellite signals, there is no suggestion to process GPS satellites as well as navigation satellite signals transmitted by Galileo satellites.

Accordingly, an object of the present invention is to reduce the time required for signal acquisition by receiving navigation satellite signals from GPS and Galileo navigation satellites even in a poor signal environment, and to use the navigation satellite signals variably for signal acquisition according to the received signal level. Accordingly, an object of the present invention is to provide an apparatus and method for obtaining an adaptive navigation satellite signal, which can improve a signal acquisition success rate of a navigation satellite signal receiver.

Another object of the present invention is to consider a navigation satellite signal transmitted by a navigation satellite such as GPS and Galileo, and a navigation satellite signal used in a signal acquisition technique in consideration of various characteristics of a reception signal level received at a receiver according to a place and a region. By using all navigation satellite signals transmitted by the navigation satellite appropriately in the reception signal environment, the adaptive navigation system can operate adaptively to the received signal strength to increase the signal acquisition probability for the navigation signal and to shorten the signal acquisition time. An apparatus and method for obtaining satellite signals are provided.

In addition, another object of the present invention is to adapt to increase the availability of navigation satellite services and systems by acquiring navigation satellite signals even under various environments of signal strength and by using not only GPS navigation satellites but also Galileo navigation satellites. The present invention provides an apparatus and method for obtaining a navigation satellite signal.

In addition, another object of the present invention is to acquire a signal by using the navigation satellite signal variably according to the environment in which the receiver for calculating the location information using the navigation satellite signal transmitted by GPS and Galileo navigation satellite is located Apparatus and method for adaptive navigation satellite signal acquisition that can improve the performance of the receiver by increasing the probability of signal acquisition, shortening the signal acquisition time, and reducing the time required for the receiver to calculate its position. To provide.

Apparatus for adaptive navigation satellite signal acquisition according to the present invention for achieving the above objects, in the apparatus for obtaining a navigation satellite signal received from GPS and Galileo navigation satellite, navigation received from the navigation satellite Monitors the received signal level of the satellite signal, selects the navigation satellite signals GPS L1, Galileo E1, GPS L5, Galileo E5a, and GPS L2C in the order of the shortest code length according to the monitored signal level. When the received signal level of the signal exceeds a predetermined threshold value, the corresponding navigation satellite signal is obtained.

In addition, the adaptive navigation satellite signal acquisition apparatus according to the present invention is a device for obtaining a navigation satellite signal received from a GPS and a Galileo navigation satellite, the spectrum for the navigation satellite signal received from the navigation satellite A spectrum estimator for estimating and detecting the signal; A copy code signal generator comprising a GPS navigation satellite code generator and a Galileo navigation satellite code generator to generate a copy code signal for the navigation satellite signal; According to whether the navigation satellite signal detected from the spectrum estimator is a GPS navigation satellite signal or a Galileo navigation satellite signal, a copy code signal of any one of the GPS navigation satellite code and the Galileo navigation satellite code is generated. A copy code signal selection switch for selecting; A copy code signal oversampler which oversamples the copy code signal selected by the copy code signal selection switch for signal correlation with a received navigation satellite signal; A matching filter provided in plurality according to the type of the received navigation satellite signal; A plurality of correlators for performing signal correlation between a copy code signal output from said copy code signal oversampler and a navigation satellite signal output from said matching filter; A synchronous accumulator accumulating the output values of the correlator; An M-Point FFT for estimating a Doppler frequency value from the synchronization accumulation result accumulated in the synchronization accumulator; An asynchronous accumulator for calculating a power value for the received navigation satellite signal based on the synchronous accumulation result; And a signal acquisition threshold exceeding determination unit that determines whether the power value calculated by the asynchronous accumulator exceeds a predetermined threshold required for signal acquisition, and wherein the signal acquisition threshold exceeding determination unit determines that the power value exceeds the threshold. When judged, the code delay value and the Doppler frequency value at the point are output as a result of signal acquisition.

In this case, the matched filter and the correlator of the adaptive navigation satellite signal acquisition apparatus according to the present invention include five matched filters and five matched filters to accommodate the GPS L1, L2C, and L5 navigation satellite signals and the Galileo E1 and E5a signals, respectively. It is characterized by consisting of a correlator.

In addition, the apparatus for acquiring an adaptive navigation satellite signal according to the present invention is a device for acquiring a navigation satellite signal received from a navigation satellite system including a GPS and a Galileo navigation satellite, wherein the navigation signal is received from the navigation satellite. Means for determining whether the satellite signal is a GPS navigation satellite signal or a Galileo navigation satellite signal; Means for selecting the navigation satellite signal to be used in order of GPS L1, Galileo E1, GPS L5, Galileo E5a, and GPS L2C having the shortest code length according to the determination result by the determination means; Means for generating a copy code signal in accordance with a determination result by means for determining whether the navigation satellite signal is a GPS navigation satellite signal or a Galileo navigation satellite signal; Means for selecting the generated copy code signal; Means for calculating a code delay and a Doppler frequency estimate for the navigation satellite signal and performing signal correlation between the navigation satellite signal and the copy code signal; And threshold setting means used to receive the navigation satellite signal and determine whether to acquire a signal for the satellite.

At this time, in the adaptive navigation satellite signal acquisition apparatus according to the present invention, the means for determining whether the received navigation satellite signal is a GPS navigation satellite signal or a Galileo navigation satellite signal, the GPS by monitoring the spectrum of the received navigation satellite signal A spectrum monitoring unit for determining L1 (1575.42 MHz), L2C (1227.60 MHz), and L5 (1176.45 MHz), and for Galileo, E1 (1575.42 MHz) and E5a (1176.45 MHz); And an information transmitter for providing information to the means for generating a copy code signal for the GPS and the Galileo signal inside the receiver.

At this time, the spectrum monitoring unit removes the noise present in the RF signal from the GPS / Galileo combined antenna that can receive both GPS L1, L2C, L5 and Galileo E1, E5a signals, amplify the signal, It consists of a module that converts the RF signal to the IF signal level, characterized in that for monitoring the spectrum of the IF signal level.

In addition, in the adaptive navigation satellite signal acquisition apparatus according to the present invention, a means for calculating a code delay and a Doppler frequency estimate for the navigation satellite signal, and performing signal correlation between the navigation satellite signal and the copy code signal, A matched filter bank unit and a correlator bank unit having two matched filters and correlators; GPS L1, Galileo E1, GPS L5, Galileo E5a, and GPS L2C with short code lengths to shorten the time required for acquisition of navigation satellite signals from GPS / Galileo navigation satellites with varying signal levels according to the ground environment. It is characterized in that consisting of; signal selection unit for selecting a signal used for the signal acquisition.

In this case, when the received signal level is -130 dBm, the signal line unit performs signal acquisition using GPS L1 as a signal for signal acquisition, and does not exceed a threshold value of the signal-to-noise ratio required for signal acquisition with a GPS L1 signal. Otherwise, the signal is acquired using the Galileo E1 signal, and the signal is acquired using the GPS L5 under a signal environment with the received signal level of about -142 dBm. If the signal is not obtained even with the GPS L5 signal, The signal acquisition is attempted using the Galileo E5a signal, and if the signal is not obtained, the signal is acquired using the GPS L2C signal, and synchronous and asynchronous accumulation is applied to each navigation satellite signal for signal acquisition. It is done.

In addition, the adaptive navigation satellite signal acquisition method according to the present invention is a method for obtaining a navigation satellite signal received from a GPS and a Galileo navigation satellite, the received signal for the navigation satellite signal received from the navigation satellite Monitors the level, selects the navigation satellite signals GPS L1, Galileo E1, GPS L5, Galileo E5a, and GPS L2C in order from the shortest code length according to the monitored reception signal level, so that the reception signal level of the selected navigation satellite signal When the predetermined threshold value is exceeded, a corresponding navigation satellite signal is obtained.

In addition, the adaptive navigation satellite signal acquisition method according to the present invention is an adaptive navigation satellite signal acquisition method for receiving and processing all navigation satellite signals transmitted by a navigation satellite such as GPS and Galileo. After receiving the navigation satellite signal from the visible satellite through the antenna, it removes the noise generated on the satellite link, amplifies the necessary navigation satellite signal, converts the RF signal into an IF signal, and converts the converted IF signal into a signal processing band. Frequency conversion process; A code generator is used to generate a copy code signal and perform correlation with the received code to synchronize the code transmitted between the received code and the copy code signal, thereby providing an approximate starting point for the navigation satellite signal code. The signal acquisition process of calculating the approximate value as well as confirming the Doppler frequency; And a signal tracking process for deriving the correct value for the code delay and the correct value for the Doppler frequency in order to calculate the correct position of the receiver in the signal tracker.

In this case, the signal acquisition process may include a first signal acquisition step of performing signal acquisition using a code of a GPS L1 signal having a shortest code length; A second signal acquisition step of performing signal acquisition using a code of a Galileo E1 signal transmitted by a Galileo navigation satellite if the signal acquisition is not performed using the code of the GPS L1 signal; If the signal is not acquired by the code of the Galileo E1 signal, a third signal acquisition is performed using at least one of a code of a GPS L5 signal and a code of a Galileo E5a signal having the same length as the code of the GPS L5 signal. step; And a fourth signal acquisition step of performing signal acquisition using the code of the GPS L2C signal if the signal acquisition is not performed even by using the code of the GPS L5 signal and the code of the Galileo E5a signal.

In this case, the second to fourth signal acquisition step is characterized by reducing the time required for signal acquisition by using a value obtained from the code of the GPS L1 signal obtained in the first signal acquisition step as an input value.

In the third signal acquisition step, signal acquisition is performed using only the data channel length of the GPS L5 signal, and when the signal strength is very weak, a pilot channel is used, but coherent integration and asynchronous accumulation are performed. It is characterized by performing signal acquisition by applying all coherent integration).

As described above, the present invention provides a navigation satellite signal for use in a signal acquisition technique in that navigation satellite signals transmitted by navigation satellites such as GPS and Galileo are various, and the reception signal level at the receiver is different depending on the place and region. In order to acquire the signal adaptively according to the environment, it is possible to use all the signals transmitted by the navigation satellites, but it is appropriate to the receiving signal environment to adapt to the possibility of signal acquisition and the received signal strength. This can reduce the signal acquisition probability and the reduction of signal acquisition time for the navigation satellite signal.

Accordingly, the present invention can contribute to increasing the availability of navigation satellite services by not only acquiring navigation satellite signals even under various environments of signal strength, but also allowing navigation satellites to use not only GPS but also Galileo navigation satellites. It is possible to receive smooth navigation satellite signals even in areas where the signal strength is weak in processing satellite signals only and in urban areas where there are many high-rise buildings.

In addition, the present invention can diversify the field using the navigation satellite system as well as the satellite navigation system can provide more accurate location information, thereby improving the utilization of the precise location information.

Apparatus and method for adaptive navigation satellite signal acquisition according to the present invention increases the reception probability of GPS and Galileo navigation satellite navigation signal, shortens the signal acquisition time, and reduces the time required for the receiver to calculate its position. Accordingly, in order to provide an adaptive navigation satellite signal acquisition apparatus and method that can not only improve the performance of a receiver but also increase the availability of navigation satellite services and systems, navigation satellites such as GPS and Galileo are GPS and Galileo navigation satellite signal complex reception processing apparatus capable of receiving and processing all the transmitted navigation satellite signal is provided.

The composite receiving processing apparatus receives a navigation satellite signal from a visible satellite such as GPS and Galileo through an antenna, removes noise generated on a satellite link, amplifies necessary navigation satellite signals, converts an RF signal into an IF signal, and IF In order to convert a signal into a signal processing band, a frequency conversion process is performed. After the frequency conversion, the receiver generates a copy code signal using a code generator to synchronize the code transmitted by the satellite, and performs a correlation process with the received code to synchronize the received code with the copy code signal. Do this. This synchronization process confirms the approximate starting point for the navigation satellite signal code as well as calculates the approximate value for the Doppler frequency.

After the signal acquisition process, the signal tracking unit must derive the correct value for the code delay and the correct value for the Doppler frequency to calculate the exact position of the receiver. In the signal acquisition process of the receiver, a navigation satellite signal transmitted by the navigation satellite is acquired. The signal acquisition method uses a GPS having the shortest code length in order to acquire a navigation satellite signal received from a GPS and a Galileo navigation satellite. By using the code of the L1 signal to perform the signal acquisition to reduce the time required for signal acquisition. If the signal acquisition is not performed using the code of the GPS L1 signal, the signal acquisition is performed using the code of the Galileo E1 signal transmitted by the Galileo navigation satellite. If the code of the Galileo E1 signal does not acquire a signal, use the code of the GPS L5 signal or the code of the same Galileo E5a signal. If signal acquisition is not performed even by using the code of the GPS L5 signal or the code of the Galileo E5a signal, the signal acquisition is performed by using the code of the GPS L2C signal.

In this case, the adaptive navigation satellite signal acquisition apparatus and method according to the present invention can reduce the time required for signal acquisition by using the value obtained from the code of the GPS L1 signal which is the most basic signal acquisition for each signal as an input value. Make sure On the other hand, when using a data channel and a pilot channel as in the GPS L5 signal, the signal acquisition is performed using the data channel when the signal is acquired using only the data length. In the very weak state, a pilot channel is used but signal acquisition is achieved by applying both coherent integration and non-coherent integration. In addition, in a signal acquisition device for all navigation satellite signals, a combination of a matching filter and fast fourier transform (FFT) technique is applied to reduce the required memory on hardware required for signal acquisition.

The apparatus and method for adaptive navigation satellite signal acquisition according to the present invention can acquire signals using various navigation satellite signals, and thus, if the receiver wants to calculate current receiver position information, the constraints for use are alleviated, as well as the signal acquisition process. By using a variety of navigation satellite signals used in the system, the acquisition of navigation satellite signals can be made faster and the acquisition of navigation satellite signals is possible even in an environment where the reception signal level is rather poor.

Apparatus and method for adaptive navigation satellite signal acquisition according to the present invention further includes a GPS navigation satellite signal as well as a Galileo navigation satellite signal in the range of signals processed by the navigation receiver in further activating the usage range of the navigation receiver. By using various navigation satellite signals to adaptively acquire navigation satellite signals according to the signal level, it is possible to reduce the possibility of signal acquisition and the time required for acquisition of navigation satellite signals, or to expand the use of satellite navigation services. It can contribute greatly. For example, the adaptive navigation satellite signal acquisition apparatus and method according to the present invention can provide accurate location information through a navigation receiver to a user who uses a navigation receiver indoors, and thus to a large number of users who utilize the location information for indoor positioning. It provides convenience and safety, and can accurately inform its own location information to the other party, which can greatly contribute to anxiety and uncertainty caused by the uncertainty of the location information.

As described above, the adaptive navigation satellite signal acquisition apparatus and method according to the present invention have various navigation satellite signals used in the navigation receiver, and because the signal level input to the receiver varies depending on the ground environment. And by acquiring the adaptive signal according to the environment, it is to contribute greatly to the application field where accurate location information is required in the difficult location or urban area. In addition, the navigation receiver, which receives a navigation satellite signal from the navigation satellite and calculates its own location, performs a cumulative time for the navigation satellite signal in order to increase the acquisition performance of the signal according to the state of the reception signal. It is possible to improve the performance of the received signal at.

An adaptive navigation satellite signal acquisition device according to the present invention comprises: a signal acquisition device having a function of more quickly and successfully acquiring a navigation satellite signal transmitted by a navigation satellite such as GPS and Galileo; Receives the navigation satellite signal transmitted by the navigation satellite in the receiver, but basically acquires the signal using the code of the GPS L1 signal, and if the signal is not acquired through this, the code of the Galileo E1 signal is used. Signal processing means for acquiring a signal using a GPS L5 or Galileo E5a signal if it is not obtained; Position information calculation means for receiving the position information transmitted by the navigation satellite in the receiver to calculate the position of the receiver itself.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a detailed description of preferred embodiments of the present invention will be given with reference to the accompanying drawings. It should be noted that the same components in the figures represent the same numerals wherever possible. Specific details are set forth in the following description, which is provided to provide a more thorough understanding of the present invention. In the following description of the present invention, detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

Hereinafter, a hat having a sunglasses according to an embodiment of the present invention will be described in detail with reference to the drawings.

First, FIG. 1 is a block diagram of an adaptive navigation satellite signal acquisition device according to the present invention, and an adaptive navigation satellite signal acquisition device for receiving a navigation satellite signal from a navigation satellite and performing signal acquisition according to the present invention, and its It is for explaining the operation of acquiring the navigation satellite signal performed in the apparatus.

As shown in FIG. 1, the apparatus for acquiring the adaptive navigation satellite signal according to the present invention includes an RF / IF signal conversion unit for quickly and efficiently acquiring a navigation satellite signal transmitted from the GPS and the Galileo navigation satellite 100. 200), carrier remover 300, I & Q signal downsampling module 400, code generator 500, code rate converter 600, signal correlator 700, signal accumulator 800 and signal acquisition threshold The excess determination unit 900 is configured.

The navigation satellite 100 is a navigation satellite on a GNSS network including a GPS satellite 110 and a Galileo satellite 120. The navigation satellite 100 uses navigation messages, time information, and PRN code allocated to each satellite in the case of the GPS navigation satellite 110, L1 (1575.42 MHz), L2C (1227.60 MHz), and L5 (1176.45 MHz). In the case of the Galileo navigation satellite 120, the navigation satellite signals E1 (1575.42 MHz) and E5a (1176.45 MHz) are transmitted to the ground.

The RF / IF signal conversion unit 200 includes an antenna 210 for receiving a navigation satellite signal from the GPS and the Galileo navigation satellite 100, and a low noise amplifier for removing noise and amplifying the signal for the received navigation satellite signal. 220, an RF / IF signal converter 230 for converting an RF signal into an IF signal, and a spectrum estimator 240 for estimating and detecting a spectrum of the navigation satellite signal. The RF / IF signal conversion unit 200 converts a radio frequency signal into a digital signal via an ADC unit for converting an RF signal into an IF signal and an analog signal for converting a signal to a navigation satellite signal. Do this.

The carrier removing unit 300 is a signal of the cosine component having a phase difference of 90 degrees with the sinusoidal signal from the RF / IF signal conversion unit 200 in order to convert the input navigation satellite signal into a processable frequency band A multiplier 310 for performing a multiplication process with an input signal, a sine and cosine generator 320 for generating sine and cosine components, and a local oscillator for generating a 28 MHz reference frequency for removing a carrier for an IF signal ( 330). The carrier removing unit 300 is divided into two types according to the shape of an input signal, which will be described in detail with reference to Equations 1 and 2 below.

First, if the received signal is a complex form, the carrier is removed from the baseband through the following equation (1).

Next, if the received signal is a real type, a process of converting the real type signal to a complex type signal in the baseband through the following equation (2).

In order to perform the above process, the carrier removing unit 300 performs a multiplication process of multiplying a signal of a cosine component having a phase difference of 90 degrees with a sine component by an input signal, and a sine generating a sine component and a cosine component. And a local oscillator 330 for generating a cosine 320 and a reference frequency of 28 MHz for removing a carrier from the IF signal.

The I & Q signal downsampling module 400 adjusts the sampling rates of the I and Q channels with respect to the input signal in order to perform correlation between the I and Q channel signals passing through the carrier removing unit 300 and the copy code signals generated inside the receiver. Downsampling to 2.046 MHz is required. To do this, signal downsampling is performed on the I & Q channel.

The code generator 500 generates a copy code signal inside the receiver to correlate the input signal down-sampled from the I & Q signal downsampling module 400. The code generator 500 is composed of a GPS PRN code generator 510 and a Galileo PRN code generator 520 as a copy code signal inside the receiver since the input navigation satellite signal is a navigation satellite signal of a GPS satellite and a Galileo satellite.

The code rate conversion unit 600 has a code selection switching unit 610 to select the corresponding PRN according to the input code among the codes generated by the code generator 500, the input signal for the selected navigation satellite signal The code over sampler 620 is configured to perform oversampling at 2,048 MHz for signal correlation.

The signal correlator 700 is an input signal down-sampled from the I & Q signal downsampling module 400 and a copy code generated by the code generator 500 and converted from a code rate by the code rate converter 600. In order to perform signal correlation of the signal, it consists of an I & Q matched filter bank 710 and an I & Q correlator bank 720.

Signals for the I and Q channels are input to the I & Q matching filter bank 710 consisting of 2,048 taps in sample units, and the input signals include five navigation satellite signals such as GPS L1, L2C, L5 and Galileo E1, E5a. As input, the I & Q matched filter bank 710 includes at least five matched filters to accommodate all of these signals.

The signal accumulator 800 includes a sync accumulator 810 for performing synchronous accumulation on the I and Q channels with respect to a signal correlated in the signal correlator 700, and a Doppler frequency for a phase of a corresponding code. In order to find the M-Point FFT 820 for converting the time domain to the frequency domain and the signal passing through the M-point FFT 820 through asynchronous accumulation to calculate the power for the code phase and Doppler frequency It consists of an asynchronous accumulator 830 for.

Finally, in order for the signal acquisition to be completed, the power value obtained through the asynchronous accumulator 830 needs to exceed a threshold required for signal acquisition. Thus, the signal acquisition threshold exceeding determination unit 900 determines the asynchronous accumulator 830. Determining whether the power value obtained through the signal exceeds the threshold required for signal acquisition.

The signal acquisition process in the adaptive navigation satellite signal acquisition apparatus according to the present invention having the structure as described above will be described in detail below with reference to FIG. 2 is a control flowchart illustrating an adaptive navigation satellite signal acquisition process according to the present invention.

2 is an RF / IF signal converter 200 for receiving a GPS / Galileo navigation satellite signal and converting it into an IF signal, calculating an I & Q signal downsampling module 300 for IF data, and a code phase delay value. Matching filter 710 for each navigation satellite signal for the signal, correlator 720 for each signal performing signal correlation with the input signal passed through the matching filter 710 and the oversampling value of the PRN code generator 800 inside the receiver. Input signals in the I and Q channels through the synchronous accumulator 810 and the asynchronous accumulator 830 that perform synchronous accumulation on the correlation values, including an M-point FFT 820 for estimating the Doppler frequency value. And an operation procedure for the signal acquisition threshold exceeding determination unit 900 that determines whether the result obtained through the sum after square and the square root of the correlation code between the signal and the copy code signal exceeds the signal acquisition threshold. Example.

The RF / IF signal conversion unit 200 receives RF signals from the GPS satellite 110 and the Galileo satellite 120 which are the navigation satellites 100, respectively. The RF / IF signal conversion unit 200 receives GPS L1 (1575.42 MHz), L2C (1227.60 MHz), and L5 (1176.45 MHz) signals from the GPS satellite 110 and E1 (1575.42 MHz) from the Galileo satellite 120. ), Receives E5a (1176.45 MHz) (S201), removes noise generated on the link between the navigation satellite 100 and the receiver, converts to an IF signal (S203), and monitors the spectrum of the signal (S205). . Through spectrum monitoring for the signal (S205), it is determined whether the navigation satellite signal is a signal transmitted by the GPS navigation satellite 110 or a signal transmitted by the Galileo navigation satellite 120 (S207).

In step S207, if it is determined whether the navigation satellite signal is a GPS signal or a Galileo signal, the I & Q signal downsampling module 300 converts IF down for each navigation satellite signal, and the received signal is a CDMA signal. To do this, pass a despread mixer to despread the signal.

The navigation satellite signal passing through the despreading mixer is provided with a matching filter bank 711 such that the corresponding signal is inputted to a matching filter for GPS L1, GPS L2C, and GPS L5, and the navigation satellite signal is a Galileo E1, E5a. A matched filter bank 713 is also provided to input corresponding information to the matched filter. The matched filter 710 performs a sequential shift function on the input sample. The number of taps of the matched filter is 2,048 and inputs to the matched filter in 0.5 chip units for the input code to extract the code delay for each signal. .

For the signal passing through the matching filter for each navigation satellite signal, the GPS copy code and the Galileo copy code generated by the code generator 500 inside the receiver are selected, and the code selection switch 610 is used for the code selection. Is used. The code selection switch 610 selects a copy code signal inside the receiver according to the information from the navigation satellite signal monitoring (S205) that performs the monitoring function for the RF navigation satellite signal, and oversamples 1.023 MHz to 2.048 MHz. Thereafter, the correlator bank 720 correlates the code of the input signal with the copy code signal generated inside the receiver.

The correlator bank 720 includes a GPS correlator 721 including a GPS L1 signal correlator, a GPS L2C correlator, and a GPS L5 correlator, and a Galileo correlator 723 including a Galileo E1 signal correlator and a Galileo E5a signal correlator. It is provided. In the correlator bank 720, if the correlation between the input signal and the copy code signal inside the receiver is precisely correlated, the signal power existing below the noise level is higher than the noise level to enable signal acquisition.

The sync accumulator 810 accumulates correlator output values in the I and Q channels, and the M Point FFT module 820 should be provided to find the Doppler frequency from the accumulated result. In the M Point FFT module 820, the FFT point value to be used must use a power of two. In order to calculate the power value for a signal based on the synchronous accumulation results in the I and Q channels, the synchronous accumulation results need to be squared, summed, and take the form of square roots. Module 830.

Subsequently, the signal acquisition threshold exceeding determination unit 900 for checking whether the signal power value calculated from the asynchronous accumulation module 830 exceeds a preset signal acquisition threshold should be provided. The threshold value of the signal acquisition used by the determination unit 900 checks whether the signal-to-noise ratio is about 5 dB or the ratio of the maximum value of the signal power and the second value is doubled and exceeds the value. The delay value and the Doppler frequency value are the result of signal acquisition (S209). Subsequently, the satellite navigation terminal apparatus performs a process of transmitting the result of signal acquisition to a signal tracking step.

3 is a control flowchart showing a message processing for acquiring an adaptive navigation satellite signal performed in a navigation satellite and a navigation satellite signal reception period according to the present invention, and showing the signal waveform in the RF spectrum measurement of the navigation satellite signal according to the present invention. On the basis of this, one embodiment of the information flow showing the signal processing flow procedure by measuring the RF spectrum of the navigation satellite signal for selectively switching the radiation code signal generator output inside the satellite navigation receiver.

The adaptive navigation satellite signal acquisition apparatus according to the present invention monitors the navigation satellite signals from the GPS and the Galileo navigation satellite 100, and at step S301, the corresponding navigation satellite signals are GPS navigation satellites through the RF spectrum of the received navigation satellite signals. By determining whether the signal is a signal or a Galileo navigation satellite signal (S303), the GPS and the Galileo navigation satellite signals perform IF and ADC (Analog to Digial Converter) functions in common (S305). The signal passing through the ADC is a digital signal, and these signals are input to the matching filter 710 in units of bits.

In the matched filter 710, the input information is shifted by 0.5 chip units to perform a code delay for a predetermined period (S307), and the sample passing through the matched filter correlates with the code from the code generator inside the receiver. S309). Through the correlation, the peak value for the code is found, and the peak value is the approximate code value, and the FFT (S311) process of converting the time domain to the frequency domain is performed to find the Doppler frequency value in the corresponding code. . The number of points used for the FFT process in step S311 should be selected in consideration of the memory capacity to be implemented, and in order to make the processing time faster, the number of points represented by the square of 2 should be selected. An approximate code delay position and a Doppler frequency value are calculated from the FFT and the synchronous accumulation process, and in order to determine whether the value is normal, a power value should be calculated. For this purpose, an asynchronous accumulation process (S313) is performed. Subsequently, the process proceeds to step S315, and it is checked whether the result value resulting from the asynchronous accumulation of the step S313 exceeds a predetermined power value (SNR) for signal acquisition, and when the value exceeds the threshold, for one channel, Signal acquisition ends.

As described above, the present invention provides a faster and more accurate signal acquisition of navigation satellite signals provided by navigation satellites such as GPS and Galileo, as well as codes for navigation satellite signals used for signal acquisition under various environments. In order to perform the signal acquisition using the variably, GPS and Galileo satellite navigation systems are used to variably use the various navigation satellite signals according to the signal strength and the position of the receiver when the navigation satellite signals are diversified. As a result, it is possible to increase the probability of success in acquiring navigation satellite signals at the receiver, and to make the signal acquisition variable under varying environments, and the visibility of satellites is low in the area where the strength of navigation satellite signals is low. It is possible to acquire signals for navigation satellite signals even in poor regions. In addition, it can be used in the navigation satellite system that can activate the navigation satellite terminal and increase the accuracy of signal acquisition of the navigation satellite receiver.

In addition, the present invention is a satellite navigation system for receiving and receiving a navigation satellite signal from GPS, Galileo, etc., receiving a satellite navigation signal, monitoring the RF spectrum of the received signal, the monitoring result is located inside the receiver By sending a copy code signal selection switch to the GPS and Galileo complex receive signal processing, it is possible to process a wider range of navigation satellite signals as well as to receive more navigation satellite signals in the terrestrial satellite navigation receiving environment. It is possible to provide a system and a method for achieving the availability of the satellite navigation system and the probability of success in the signal acquisition and the signal acquisition more quickly, and an apparatus for adaptively processing the navigation satellite signal is currently A wider range of navigation satellite signals can be processed to improve the availability of the navigation system.

In addition, the present invention can contribute to the acquisition of signals more quickly and accurately in an environment where navigation satellite pluralization and navigation satellite systems are greatly activated, and can greatly contribute to the development of applications using navigation satellite receivers. .

As described above, the method of the present invention is implemented in a program and a document and can be read by a computer in a form of a computer readable recording medium (CD), random access memory (RAM), read only memory (ROM), and floppy. Disk, hard disk, magneto-optical disk, etc.). This process can be easily carried out by those of ordinary skill in the art.

Meanwhile, in the detailed description of the present invention, specific embodiments have been described, but various modifications are possible without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited by the described embodiments, but should be determined by the scope of the appended claims and equivalents thereof.

1 is a block diagram of an adaptive navigation satellite signal acquisition device according to the present invention;

2 is a control flowchart illustrating an adaptive navigation satellite signal acquisition process according to the present invention;

3 is a control flowchart showing message processing for adaptive navigation satellite signal acquisition performed during a navigation satellite and a navigation satellite signal reception period according to the present invention;

 (Description of Major Symbols in the Drawing)

100: GPS satellites (GPS / Galileo) 110: Galileo satellite

120: GPS satellite 200: RF / IF signal conversion unit

210: reception antenna 220: low noise amplifier (LNA)

230: RF to IF converter 240: spectrum monitoring unit

300: carrier removal unit 310: multiplication module

320: sine / cosine generator 330: local oscillator

400: I / Q signal downsampling module 500: code generator

510: GPS navigation satellite signal code generator

520: Galileo navigation satellite signal code generator

600: code rate conversion unit 610: code selection switching unit

620: code-up sampling unit 700: signal correlation unit

710: matched filter bank 720: signal correlator bank

800: signal accumulation unit 810: synchronous signal accumulation unit

820: FFT processor 830: asynchronous signal accumulation unit

900: signal acquisition threshold exceeded determination unit

Claims (13)

An apparatus for obtaining a navigation satellite signal received from a GPS and a Galileo navigation satellite, The reception signal level of the navigation satellite signal received from the navigation satellite is monitored, and navigation satellite signals GPS L1, Galileo E1, GPS L5, Galileo E5a, and GPS L2C are arranged in order of the shortest code length according to the monitored reception signal level. And sequentially selecting and acquiring the corresponding navigation satellite signal when the received signal level of the selected navigation satellite signal exceeds a preset threshold value. An apparatus for obtaining a navigation satellite signal received from a GPS and a Galileo navigation satellite, A spectrum estimator for estimating and detecting a spectrum of a navigation satellite signal received from the navigation satellite; A copy code signal generator comprising a GPS navigation satellite code generator and a Galileo navigation satellite code generator to generate a copy code signal for the navigation satellite signal; According to whether the navigation satellite signal detected from the spectrum estimator is a GPS navigation satellite signal or a Galileo navigation satellite signal, a copy code signal of any one of the GPS navigation satellite code and the Galileo navigation satellite code is generated. Copy code signal selection switch to select; A copy code signal oversampler which oversamples the copy code signal selected by the copy code signal selection switch for signal correlation with a received navigation satellite signal; A matching filter provided in plurality according to the type of the received navigation satellite signal; A plurality of correlators for performing signal correlation between a copy code signal output from said copy code signal oversampler and a navigation satellite signal output from said matching filter; A synchronous accumulator accumulating the output values of the correlator; An M-Point FFT for estimating a Doppler frequency value from the synchronization accumulation result accumulated in the synchronization accumulator; An asynchronous accumulator for calculating a power value for the received navigation satellite signal based on the synchronous accumulation result; And And a signal acquisition threshold exceeding determination unit for determining whether the power value calculated by the asynchronous accumulator exceeds a predetermined threshold required for signal acquisition. And the signal acquisition threshold exceeding determination unit outputs a code delay value and a Doppler frequency value at the point as a result of signal acquisition when it is determined that the power value exceeds the threshold value. The method of claim 2, wherein the matching filter and the correlator, An adaptive navigation satellite signal acquisition device, comprising five matching filters and a correlator for receiving GPS L1, L2C, and L5 navigation satellite signals and Galileo E1 and E5a signals, respectively. An apparatus for obtaining a navigation satellite signal received from a navigation satellite system comprising a GPS and a Galileo navigation satellite, Means for determining whether a navigation satellite signal received from the navigation satellite is a GPS navigation satellite signal or a Galileo navigation satellite signal; Means for selecting the navigation satellite signal to be used in order of GPS L1, Galileo E1, GPS L5, Galileo E5a, and GPS L2C having the shortest code length according to the determination result by the determination means; Means for generating a copy code signal in accordance with a determination result by means for determining whether the navigation satellite signal is a GPS navigation satellite signal or a Galileo navigation satellite signal; Means for selecting the generated copy code signal; Means for calculating a code delay and a Doppler frequency estimate for the navigation satellite signal and performing signal correlation between the navigation satellite signal and the copy code signal; And And a threshold setting means used to determine whether to acquire a signal for a corresponding satellite by receiving the navigation satellite signal. 5. The apparatus of claim 4, wherein the means for determining whether the received navigation satellite signal is a GPS navigation satellite signal or a Galileo navigation satellite signal, Monitor the spectrum of the received navigation satellite signal to see L1 (1575.42 MHz), L2C (1227.60 MHz), L5 (1176.45 MHz) for GPS, E1 (1575.42 MHz), E5a (1176.45 MHz) for Galileo. A spectrum monitoring unit to determine; And And an information transmitter for providing information to the means for generating a copy code signal for a GPS and a Galileo signal inside the receiver. The method of claim 5, wherein the spectrum monitoring unit, Eliminates noise present in RF signals from GPS / Galileo antennas capable of receiving GPS L1, L2C, L5 and Galileo E1, E5a signals, amplifies the signal, and boosts the RF signal to the IF signal level. Apparatus for adaptive navigation satellite signal acquisition comprising a module for converting the signal to the IF signal level. 5. The apparatus of claim 4, comprising a matched filter bank and a correlator bank to calculate a code delay and a Doppler frequency estimate for the navigation satellite signal and to perform signal correlation between the navigation satellite signal and the copy code signal. A matched filter bank unit and a correlator bank unit having a plurality of matched filters and correlators; And GPS L1, Galileo E1, GPS L5, Galileo E5a, and GPS L2C, which have shorter code lengths, are used to shorten the time required for acquisition of navigation satellite signals from GPS / Galileo navigation satellites with varying signal levels depending on the ground environment. Adaptive navigation satellite signal acquisition device comprising a; signal pre-selection for selecting a signal used for the signal acquisition. The method of claim 7, wherein the signal preselection, If the received signal level is -130 dBm, the signal acquisition is performed using GPS L1 as a signal for signal acquisition, and the Galileo E1 signal is used unless the threshold value of the signal-to-noise ratio required for signal acquisition is obtained with the GPS L1 signal. Perform signal acquisition, Under the low signal environment of the received signal level of about -142 dBm, signal acquisition is performed using GPS L5. If the signal is not acquired even with the GPS L5 signal, the signal acquisition is attempted using the Galileo E5a signal. If the signal is not obtained, the signal acquisition is performed using the GPS L2C signal. Adaptive navigation satellite signal acquisition device, characterized in that the synchronous and asynchronous accumulation is applied to each navigation satellite signal for signal acquisition. A method for obtaining navigation satellite signals received from GPS and Galileo navigation satellites, The reception signal level of the navigation satellite signal received from the navigation satellite is monitored, and navigation satellite signals GPS L1, Galileo E1, GPS L5, Galileo E5a, and GPS L2C are arranged in order of the shortest code length according to the monitored reception signal level. And sequentially selecting and acquiring the corresponding navigation satellite signal when the received signal level of the selected navigation satellite signal exceeds a preset threshold value. An adaptive navigation satellite signal acquisition method for receiving and processing all navigation satellite signals transmitted by a navigation satellite such as GPS and Galileo, After receiving the navigation satellite signal from the visible satellite such as GPS and Galileo through the antenna, the noise generated on the satellite link is removed, the necessary navigation satellite signal is amplified, the RF signal is converted into the IF signal, and the converted IF signal is converted into A frequency conversion process of converting into a signal processing band; A code generator is used to generate a copy code signal and perform correlation with the received code to synchronize the code transmitted between the received code and the copy code signal, thereby providing an approximate starting point for the navigation satellite signal code. The signal acquisition process of calculating the approximate value as well as confirming the Doppler frequency; And And a signal tracking process for deriving the correct value for the code delay and the correct value for the Doppler frequency in order to calculate the exact position of the receiver in the signal tracker. The method of claim 10, wherein the signal acquisition process comprises: A first signal acquisition step of performing signal acquisition using a code of a GPS L1 signal having a shortest code length; A second signal acquisition step of performing signal acquisition using a code of a Galileo E1 signal transmitted by a Galileo navigation satellite if the signal acquisition is not performed using the code of the GPS L1 signal; If the signal is not acquired by the code of the Galileo E1 signal, a third signal acquisition is performed using at least one of a code of a GPS L5 signal and a code of a Galileo E5a signal having the same length as the code of the GPS L5 signal. step; And If the signal is not obtained even by using the code of the GPS L5 signal and the code of the Galileo E5a signal, the fourth signal acquisition step of performing a signal acquisition using the code of the GPS L2C signal; Navigation satellite signal acquisition method. The method of claim 11, wherein the second to fourth signal acquisition step, Adaptive navigation satellite signal acquisition method characterized in that the time required for signal acquisition is reduced by using the value obtained from the code of the GPS L1 signal obtained in the first signal acquisition step as an input value. The method of claim 11 or 12, wherein the third signal acquisition step, Signal acquisition is performed using only the data channel length of the GPS L5 signal, and when the signal strength is very weak, the pilot channel is used, but the signal is applied by applying both coherent integration and non-coherent integration. Adaptive navigation satellite signal acquisition method, characterized in that performing the acquisition.

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