JP2011133334A - Positioning apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a positioning apparatus suitable for quickly capturing a GPS satellite signal when a receive environment is improved. <P>SOLUTION: The positioning apparatus includes: a generator for generating a reference clock for composing a regeneration frequency of a receive channel; an adjuster for adjusting the regeneration frequency by changing a correction value of the reference clock so as to match the regeneration frequency with a carrier frequency of the GPS satellite signal; a holder for holding the correction value set at final positioning; a determiner for determining whether a current position is a capture disabled position at which the GPS satellite signal can not be captured; and a detector for detecting a movement from the capture disabled position. When the movement from the capture disabled position is detected, the currently-set correction value is set and changed to the correction value maintained by the correction holder, so that the regeneration frequency is continuously adjusted. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a positioning device that performs positioning by GPS (Global Positioning System), and more particularly, to a positioning device suitable for quickly capturing a GPS satellite signal when the reception environment is improved.

  GPS is a positioning system for measuring position information and the like of an object using GPS satellite signals transmitted from GPS satellites orbiting the earth, and is widely used in daily life.

  In GPS, a plurality of GPS satellites share the same frequency band and transmit GPS satellite signals by a CDMA (Code Division Multiple Access) method. Specifically, the GPS satellite signal is obtained by a navigation message as a communication signal including clock information and orbit information of the GPS satellite, and a PRN code (Pseudo Random Noise code) as a spread code determined for each GPS satellite. This is a BPSK (Binary Phase Shift Keying) modulation of a 1575.42 MHz carrier. The GPS receiver selects more than the number of GPS satellites required in principle, receives the GPS antenna, generates a PRN code corresponding to the received GPS satellite, and converts the phase of the generated PRN code into a GPS satellite signal. The navigation data is demodulated by multiplying in synchronization. The GPS receiver performs calculations using the navigation data obtained by the demodulation process, and generates position information, azimuth information, movement speed information, and the like of the object. In the following, for convenience of explanation, position measurement, azimuth measurement, movement speed measurement, etc. of an object using a GPS satellite signal by a GPS receiver will be referred to as “GPS positioning”.

In order to capture and track a GPS satellite signal by the reception channel of the GPS receiver, it is necessary to match the frequency fp of the reproduction carrier signal and the reproduction code signal of the reception channel with the carrier frequency fc of the GPS satellite signal. For the carrier frequency fc, the designed carrier frequency is defined as fco, the error of the GPS satellite atomic clock (external reference clock error) is defined as Δfsat, and the Doppler error due to the relative velocity between the GPS satellite and the GPS receiver is defined as Δfdop. When defined, it is expressed by the following formula (1).
fc = fco + Δfsat + Δfdop (1)
The reproduction frequency fp is defined by the following equation (2) when an error due to the influence of individual differences in the reference clock mounted on the GPS receiver, ambient temperature, and aging is defined as Δfxo, and the reproduction frequency correction value is defined as fpAdj. ).
fp = fco + Δfxo + fpAdj (2)

  The design frequency fco is a fixed value. The clock error Δfxo can be measured by the GPS receiver performing a positioning operation. The external reference clock error Δfsat and the Doppler error Δfdop can be estimated from the navigation message obtained when the GPS satellite signal is demodulated. In order to make the reproduction frequency fp coincide with the carrier frequency fc, it is necessary to adjust the reproduction frequency correction value fpAdj which is an unknown value. The GPS receiver mainly adjusts the correction value ΔfxoAdj for the clock error Δfxo to determine the reproduction frequency correction value fpAdj while correcting the error component that cannot be removed by the external reference clock error Δfsat and the Doppler error Δfdop.

  A product for an end user including this type of GPS receiver includes a car navigation device mounted on a vehicle such as a general passenger car. A specific configuration of the car navigation device is described in Patent Document 1, for example. The car navigation device described in Patent Literature 1 checks whether GPS satellite signals are captured every predetermined time while the vehicle is located in an underground parking lot or a three-dimensional parking lot where GPS satellite signals cannot be captured. The car navigation device quickly removes the vehicle position error that occurred during GPS non-positioning. Therefore, when the GPS satellite signal can be captured, the car navigation device assumes that the vehicle is located at the underground parking lot exit, and determines the vehicle position on the screen. It is configured to modify the underground parking lot exit.

JP 2003-279361 A

  By the way, a general GPS receiver sets a clock error correction value ΔfxoAdj given to each reception channel immediately after power-on to a value used at the time of last positioning. However, if the ambient temperature has changed significantly from the previous GPS positioning, or if a large error is inherent in the previous GPS positioning result due to the influence of multipath, etc., the error in estimating the clock error correction value ΔfxoAdj is incorrect. It may have occurred. When the GPS receiver cannot capture a GPS satellite signal (for example, when it is located in an underground parking lot or a multi-story parking lot), the clock error correction value ΔfxoAdj is changed stepwise in consideration of the possibility of this kind of estimation error. Then, the reproduction frequency fp is adjusted to try to acquire the GPS satellite signal.

  However, in this case, the clock error correction value ΔfxoAdj changes during the period when the GPS satellite signal cannot be captured, the reproduction frequency deviates from the actual carrier frequency, and the initial position calculation time TTFF (Time To First Fix) is pointed out. For example, in the configuration described in Patent Document 1, it is not possible to reduce the time required for capturing the GPS satellite signal. Therefore, it takes time to acquire accurate position information, and the above inconvenience cannot be solved. .

  Therefore, the present invention has been made in view of the above circumstances, and an object of the present invention is to provide a positioning device suitable for quickly acquiring a GPS satellite signal when the reception environment is improved.

  A positioning apparatus according to an embodiment of the present invention that solves the above-described problems is an apparatus that performs positioning by capturing and tracking different GPS satellite signals for each reception channel. Such a positioning device includes a clock generation means for generating a reference clock constituting the reproduction frequency of the reception channel, and by changing the correction value of the reference clock so that the reproduction frequency matches the carrier frequency of the GPS satellite signal. Reproduction frequency adjusting means for adjusting the reproduction frequency, correction value holding means for holding the correction value set at the time of the last positioning, and determining whether or not the current position is a non-capturing position where the GPS satellite signal cannot be captured A non-capturing position determination unit that performs the movement detection unit that detects a movement from the non-capturing position. The reproduction frequency adjusting means of this positioning device changes the currently set correction value to the correction value held in the correction value holding means when the movement from the non-capturing position is detected, and reproduces the reproduction frequency. Continue adjusting.

  According to the positioning device of the present invention, it takes time to capture a GPS satellite signal when the reception environment is improved due to the search range gradually deviating from the carrier frequency in an environment where the GPS satellite signal cannot be received. Inconvenience is effectively avoided.

  The positioning device according to the present invention is an autonomous positioning means for performing position measurement by autonomous navigation, and a means for determining a final position using at least one positioning result by GPS or autonomous navigation, wherein the determined fixed position Is determined to be a non-captured position, position determination means for determining the fixed position using only the positioning result of the autonomous navigation, and a mark of the current position on the map around the fixed position on the screen It is good also as a structure further provided with the map screen display means to display. In this case, when the confirmed position moves from the uncapable position on the map, or when the confirmed position is map-matched on any road on the map, the movement detection means starts from the uncaptured position of the actual current position. Detecting movement.

  Another type of positioning device may further include a light amount detecting means for detecting the light amount. The movement detection means in this form detects the movement of the actual current position from the uncapturable position when the light quantity detection means detects a light quantity that is equal to or greater than a predetermined threshold.

  According to the positioning device of the present invention, it takes time to capture a GPS satellite signal when the reception environment is improved due to the search range gradually deviating from the carrier frequency in an environment where the GPS satellite signal cannot be received. Inconvenience is effectively avoided and rapid acquisition of GPS satellite signals is achieved.

It is a block diagram which shows the structure of the car navigation apparatus of embodiment of this invention. It is a block diagram which shows the structure of the GPS receiver of embodiment of this invention. It is a block diagram which shows the structure of the receiving channel which DSP provided with the GPS receiver of embodiment of this invention has. It is a flowchart of the frequency search process performed in the embodiment of the present invention. It is a figure for demonstrating the frequency search process performed in embodiment of this invention.

  Hereinafter, a car navigation apparatus equipped with a GPS receiver according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a block diagram showing a configuration of a car navigation device 200 mounted on a vehicle such as a general passenger car. As shown in FIG. 1, the car navigation device 200 includes a GPS receiver 100, a CPU (Central Processing Unit) 130, a gyro sensor 132, a vehicle speed sensor 134, a ROM (Read Only Memory) 136, a RAM (Random Access Memory) 138, An HDD (Hard Disk Drive) 140, a display unit 142, an input unit 144, a VRAM (Video Random Access Memory) 146, a communication interface 148, and a light amount sensor 150 are included.

  The CPU 130 performs overall control of the car navigation device 200. The CPU 130 operates in cooperation with each component of the car navigation device 200 to realize various functions.

  The GPS receiver 100 captures and tracks more GPS satellite signals than necessary for GPS positioning from a plurality of GPS satellites, performs GPS positioning, and outputs the obtained GPS positioning results to the CPU 130. GPS positioning by the GPS receiver 100 is performed once per second, for example.

  Both the gyro sensor 132 and the vehicle speed sensor 134 are known DR (Dead Reckoning) sensors. The gyro sensor 132 measures the angular velocity related to the direction in the horizontal plane of the vehicle on which the car navigation device 200 is mounted, and outputs the measurement result to the CPU 130. The vehicle speed sensor 134 detects the rotational speeds of the left and right drive wheels of the vehicle, and outputs the number of pulses corresponding to the detection result to the CPU 130.

  The ROM 136 stores various programs for executing navigation processing. These programs are loaded into the work area of the RAM 138 when the system is activated. The CPU 130 executes the loaded program.

  CPU130 performs DR positioning calculation using the output signal of each DR sensor, and acquires DR positioning result. Next, the obtained DR positioning result and the GPS positioning result of the GPS receiver 100 are compared with each other in consideration of the estimated error value for each positioning result. When the CPU 130 refers to the comparison result and detects that the accuracy of the DR positioning result has not decreased, the CPU 130 determines the DR positioning result as the final positioning result. On the other hand, when a decrease in accuracy of the DR positioning result is detected, the final positioning result is calculated by correcting the DR positioning result using the GPS positioning result. When there is no output of the GPS positioning result, the CPU 130 sets the DR positioning result as the final positioning result without performing the above comparison process.

  CPU 130 searches the map database in HDD 140 using the determined positioning result as a key, and cuts out a map around the vehicle position. The predetermined area of the RAM 138 constitutes a wider image buffer than the screen size (resolution) of the display unit 142. The CPU 130 draws the extracted map data in the image buffer, performs geometric processing to rotate and move the map according to the direction of the vehicle, etc., and designates the image area in the image buffer according to the processing result I do. The CPU 130 also arranges the vehicle position mark on the map by map matching.

  The map database may be stored in another storage medium such as a CD-ROM or DVD-ROM, or may be stored in a server installed at a remote location. . In the latter case, the car navigation apparatus 200 can access the map distribution server via the network by the communication interface 148, download necessary map data from the server, and use it for navigation. In this case, the car navigation device 200 does not need to have a map database.

  The VRAM 146 is a memory that holds the contents displayed directly on the display unit 142 and has an image area corresponding to the screen size of the display unit 142. The contents drawn in the designated image area in the image buffer are transferred to the VRAM 146. When the drawing result is transferred to the VRAM 146, for example, a surrounding map based on the vehicle position is displayed on the display screen of the display unit 142.

  In addition, when the destination is set by the operation of the input unit 144 by the user, the CPU 130 also performs well-known navigation processing for the destination.

  FIG. 2 is a block diagram showing the configuration of the GPS receiver 100. As shown in FIG. 2, the GPS receiver 100 includes an antenna 102, a multiplier 104, a frequency synthesizer 106, an LPF (Low Pass Filter) 108, an A / D converter 110, a DSP (Digital Signal Processor) 112, a CPU 114, and a clock. 116 and a memory 118.

  A GPS satellite signal transmitted from the GPS satellite is received by the antenna 102. The received signal received by the antenna 102 is subjected to noise outside the GPS satellite signal band (for example, a band significantly different from 1.57542 GHz) through a low noise amplifier (not shown), a filter that passes a predetermined frequency, and the like. . The received signal is input to the multiplier 104 after noise removal.

  Multiplier 104 down-converts the received signal to an intermediate frequency (IF (Intermediate Frequency) signal) suitable for signal processing such as filtering based on the oscillation frequency of frequency synthesizer 106 and outputs the result to LPF 108. The IF signal is input to the A / D converter 110 after noise removal by the LPF 108. The A / D converter 110 samples the IF signal, converts it to a digital IF signal, and outputs it to the DSP 112.

  The number of GPS satellites to be acquired and tracked for the GPS receiver 100 to perform the positioning calculation is at least three in the case of two-dimensional positioning and at least four in the case of three-dimensional positioning. In the present embodiment, for example, two-dimensional positioning is performed.

  The DSP 112 processes the digital IF signal generated based on the GPS satellite signal of each GPS satellite with a circuit of another system to simultaneously capture and simultaneously track a plurality of GPS satellites. have. Each reception channel captures and tracks all receivable GPS satellite signals (or GPS satellite signals transmitted from GPS satellites designated by the CPU 114), and acquires navigation messages, pseudoranges, Doppler shift amounts, etc. To do. The CPU 114 calculates a GPS positioning solution based on these data.

  FIG. 3 is a block diagram showing the configuration of the reception channel 1 that the DSP 112 has. Each reception channel is configured identically and performs the same signal processing. Speaking of different points in each reception channel, the signal processing is performed on GPS satellite signals transmitted from different GPS satellites (in other words, GPS satellite signals modulated by different PRN codes). Only. Therefore, a detailed description of the reception channels 2 to n will be omitted in the following detailed description of the reception channel 1.

  The reception channel 1 is roughly divided into a carrier tracking loop 10 and a code tracking loop 30. The carrier tracking loop 10 is a PLL (Phase Lock Loop) and is a circuit for locking the carrier. The multipliers 12 and 14, the integration & dump filter 16, the carrier loop discriminator 18, the carrier loop loop, and the like. A filter 20, an adder 22, and a carrier NCO (Numerically Controlled Oscillator) 24 are provided. The code tracking loop 30 is a DLL (Delay Lock Loop), and is a circuit for locking the code. The multipliers 32 and 34, the integration and dump filters 36 and 38, the code loop discriminator 40, the code loop A loop filter 42, adders 44 and 46, a code NCO 48, a PRN code generator 50, and a 3-bit shift register 52 are included.

  The digital IF signal output from the A / D converter 110 is input to the multiplier 12 of the carrier tracking loop 10. The multiplier 12 performs quadrature demodulation on the digital IF signal based on the reproduced carrier signal output from the carrier NCO 24, converts it into an I signal and a Q signal, and outputs the signal. The reproduced carrier signal is a signal generated by the carrier NCO 24. The I (In-phase) signal is an in-phase component in quadrature demodulation. The Q (Quadra-phase) signal is a component orthogonal to the I signal. In this specification, for simplification of description, the I signal and the Q signal are collectively abbreviated as “IQ signal”.

  The IQ signal output from the multiplier 12 is input to the multiplier 14 and also input to the multipliers 32 and 34 of the code tracking loop 30. The multiplier 14 despreads the IQ signal based on the reproduction code P output from the 3-bit shift register 52 of the code tracking loop 30 and demodulates the IQ signal into a baseband signal. Output. The reproduction code P is a signal generated by the code tracking loop 30 (more precisely, the 3-bit shift register 52), and is a reference code for the PRN code.

  The integration & dump filter 16 integrates and dumps the baseband signal and outputs it to the carrier loop discriminator 18. The carrier loop discriminator 18 discriminates the input signal in accordance with a predetermined voltage level and outputs it to the carrier loop filter 20. The carrier loop filter 20 performs a predetermined filtering process on the input signal, and outputs it to the adder 22 as an NCO control signal and also outputs it to the adder 44 of the code tracking loop 30.

  In addition to the NCO control signal from the carrier loop filter 20, a correction signal for correcting the carrier frequency output from the CPU 114 is input to the adder 22. The adder 22 adds these signals and outputs them to the carrier NCO 24. The carrier NCO 24 generates a reproduced carrier signal based on the input signal from the adder 22 and the reference clock of the clock 116, and outputs it to the multiplier 12.

  The multiplier 32 despreads the IQ signal based on the reproduction code E output from the 3-bit shift register 52, demodulates it into a baseband signal, and outputs it to the integration & dump filter 36. The multiplier 34 despreads the IQ signal based on the reproduction code L output from the 3-bit shift register 52, demodulates it to a baseband signal, and outputs it to the integration & dump filter 38. The reproduction codes E and L are signals generated by the 3-bit shift register 52 and are reference codes for the PRN code.

  The integration and dump filters 36 and 38 integrate and dump the baseband signal and output the result to the code loop discriminator 40. The cord / loop discriminator 40 discriminates the input signal according to a predetermined voltage level and outputs it to the cord / loop filter 42. The code loop filter 42 performs a predetermined filtering process on the input signal and outputs the result to the adder 44.

  The adder 44 adds the NCO control signal output from the carrier loop filter 20 and the signal output from the code loop filter 42 and outputs the result to the adder 46. In addition to the signal from the adder 44, the adder 46 receives a correction signal for correcting the frequency of the reproduction code output from the CPU 114. The adder 46 adds these signals and outputs them to the code NCO 48. The code NCO 48 operates based on the reference clock of the clock 116, performs predetermined processing on the input signal from the adder 46, and outputs it to the PRN code generator 50. The PRN code generator 50 generates a code correlated with the GPS satellite signal and outputs the code to the 3-bit shift register 52. The 3-bit shift register 52 creates reproduction codes P, E, and L (that is, reference codes of PRN codes) based on the input signal and outputs them to the multipliers 14, 32, and 34, respectively.

  By performing the above-described series of processing in the carrier tracking loop 10, the PRN code of the GPS satellite signal is acquired. In addition, by performing the above-described series of processing in the code tracking loop 30, the PRN code and each reproduction code signal generated in the reception channel 1 are phase-synchronized and a navigation message is acquired. In the reception channel 1, GPS satellite coordinates, external reference clock error Δfsat, Doppler shift amount (Doppler error Δfdop), carrier frequency fc, carrier phase, GPS time lag in the GPS receiver 100, and the like are calculated based on the navigation message.

  In the process of synchronizing the GPS satellite signal with the PRN code in the code tracking loop 30, the propagation time of the GPS satellite signal from the GPS satellite to the GPS receiver 100 is acquired. The reception channel 1 calculates a pseudo distance between the GPS satellite and the GPS receiver 100 based on the coordinates of the GPS satellite and the propagation time, and outputs the pseudo distance to the CPU 114.

  The CPU 114 calculates a GPS positioning solution including pre-estimation information such as the current position, moving speed, direction, and the like based on each measurement value, data, pseudorange, etc. calculated based on the navigation message acquired in each reception channel. To the CPU 130.

  Incidentally, the error fxo included in the reference clock of the clock 116 includes a deviation due to individual differences, and fluctuates due to the influence of ambient temperature and aging. Such a clock error Δfxo greatly affects the accuracy of the GPS positioning solution. In the present embodiment, the correction value ΔfxoAdj for the clock error Δfxo is appropriately set to achieve high speed such as TTFF.

  FIG. 4 is a flowchart of the frequency search process executed in this embodiment. FIG. 5 is a diagram for explaining the frequency search process. FIG. 5 schematically shows the entire frequency search range divided into predetermined frequency search range widths (ranges a to e). This frequency search process is started when the system of the car navigation apparatus 200 is activated. In the following description and drawings in this specification, each step of the frequency search process is abbreviated as “S”.

  In the process of S1, each reception channel of the GPS receiver 100 captures the target GPS satellite signal immediately after power-on, so that the reproduction frequency fp is corrected with the clock error correction value ΔfxoAdj_Pre used at the end of the previous positioning. An initial reproduction frequency fp1 is calculated. The reception channel starts searching for a predetermined frequency search range width centered on the initial reproduction frequency fp1. The first search is performed within the frequency search range width (here, range a in FIG. 5) to which the initial reproduction frequency fp1 belongs.

  The clock error correction value ΔfxoAdj_Pre is held in the memory 118 at the previous positioning. Specifically, the memory 118 has two areas, one holding the clock error correction value ΔfxoAdj_Pre, and the other overwriting the clock error correction value ΔfxoAdj when the last positioning was performed during the current system operation. Is configured to do. At the next system startup, the former clock error correction value ΔfxoAdj_Pre is erased, and the latter clock error correction value ΔfxoAdj is designated as a new clock error correction value ΔfxoAdj_Pre.

  In the process of S2, it is determined whether or not the vehicle is located at a place where a GPS satellite signal cannot be captured, such as an underground parking lot or a multilevel parking lot. For example, when the GPS satellite signal cannot be captured and the vehicle position on the map screen is located in the parking lot (S2: YES), the process proceeds to S3. In other cases (S2: NO), the process proceeds to S4.

In the process of S3, it is determined whether or not the vehicle has left the basement parking lot or multistory parking lot. In particular,
(1) The vehicle position calculated using only the DR positioning result passes through the parking lot exit on the map (2) The vehicle position on the map matches any road by map matching (3) Light quantity sensor When any one of 150 detects a light amount equal to or greater than a predetermined threshold, it is determined that the vehicle has left the parking lot. However, the condition (3) is applied only when it is detected that it is daytime by a timing means such as a built-in timer (not shown).

  When the delivery is not detected (S3: NO), the search operation is performed at the set search frequency, and the target GPS satellite signal is captured (S4). Next, it is determined whether or not the target GPS satellite signal has been captured (S5). If the GPS satellite signal has been captured (S5: YES), this process ends. If the GPS satellite signal cannot be captured (S5: NO), it is determined whether or not the search has been performed for all frequencies within the set frequency search range width (S6). If an unsearched frequency remains (S6: NO), the clock error correction value ΔfxoAdj is added (or subtracted) by a predetermined value to shift the search frequency (S7), and the process returns to S3. When the search is performed for all the frequencies within the set frequency search range width (S6: YES), the clock error correction value ΔfxoAdj is changed to switch the frequency search range width (S8). The frequency search range width is switched in the order of ranges a, b, c, d, and e until a GPS satellite signal is captured.

  On the other hand, when the delivery is detected in the process of S3 (S3: YES), the clock error correction value ΔfxoAdj is returned to the clock error correction value ΔfxoAdj_Pre, and the reproduction frequency fp is reset to the initial reproduction frequency fp1 (S9). , S4 and subsequent processes are executed.

  Here, consider a case where the carrier frequency fc of the target GPS satellite belongs to the range a in FIG. In an environment where a GPS satellite signal can be received, the signal can be quickly captured by performing a search in the range a in the initial stage. On the other hand, in an environment where GPS satellite signals cannot be received, conventionally, since the search range deviates from the carrier frequency fc, it takes time to capture signals even if the reception environment is improved. However, in the present embodiment, when the delivery is detected, that is, when the possibility of receiving the GPS satellite signal becomes high, the reproduction frequency fp is corrected with the clock error correction value ΔfxoAdj_Pre used at the end of the previous positioning. The initial reproduction frequency fp1 is set. As a result, the search range returns to the range a, so that rapid signal acquisition is achieved.

  The above is the description of the embodiment of the present invention. The present invention is not limited to the above-described configuration, and various modifications can be made within the scope of the technical idea of the present invention.

1 to n Reception channel 100 GPS receiver 116 Clock 118 Memory 130 CPU
200 Car navigation system

Claims (4)

In a positioning device that captures and tracks different GPS (Global Positioning System) satellite signals for each receiving channel,
Clock generating means for generating a reference clock constituting the reproduction frequency of the reception channel;
Reproduction frequency adjusting means for adjusting the reproduction frequency by changing the correction value of the reference clock so that the reproduction frequency matches the carrier frequency of the GPS satellite signal;
Correction value holding means for holding the correction value set at the time of the last positioning;
A non-capturing position determining means for determining whether or not the current position is a non-capturing position where the GPS satellite signal cannot be captured;
A movement detecting means for detecting movement from the uncapturable position;
Have
The reproduction frequency adjusting means changes the currently set correction value to the correction value held in the correction value holding means when movement from the uncaptured position is detected, and A positioning device characterized by continuing the adjustment. Autonomous positioning means for measuring position by autonomous navigation;
Means for determining a final position using at least one positioning result by the GPS or the autonomous navigation, and while the determined fixed position is determined to be the non-captured position, Position determining means for determining the determined position using only the positioning result;
Map screen display means for arranging a mark of the current position on the map around the determined position and displaying it on the screen;
Further comprising
The said movement detection means detects the movement from the said non-capturing position of an actual present position, when the fixed position moves from the non-capturing position on the map. Positioning device. Autonomous positioning means for measuring position by autonomous navigation;
Means for determining a final position using at least one positioning result by the GPS or the autonomous navigation, and while the determined fixed position is determined to be the non-captured position, Position determining means for determining the determined position using only the positioning result;
Map screen display means for arranging a mark of the current position on the map around the determined position and displaying it on the screen;
Further comprising
The movement detection means detects movement of the actual current position from the non-capturing position when the confirmed position is map-matched on any road of the map. The described positioning device. A light amount detecting means for detecting the light amount;
The positioning according to claim 1, wherein the movement detection unit detects a movement of the actual current position from the uncaptured position when the light amount detection unit detects a light amount equal to or greater than a predetermined threshold. apparatus.

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