JP2006311019A - Location detection system for mobile terminal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a location detection system for a mobile terminal capable of simply detecting the location of the mobile terminal being a location detection object (object to be searched). <P>SOLUTION: The system registers in advance a radio wave characteristic of a signal transmitted from the mobile terminal while the mobile terminal is located at a particular location desired by a user. When detecting the location of the mobile terminal, a location detector transmits a call signal to the mobile terminal, and the mobile terminal returns a response signal accordingly. When the radio wave characteristic of the response signal is coincident with the registered radio wave characteristic, the location detector informs of it that the mobile terminal is at the particular location, and when dissident, the location detector informs of a distance up to the mobile terminal and a direction or the like of the location of the mobile terminal relative to its own location. Further, when receiving no response signal, the location detector informs of it that the mobile terminal is at the outside of a communication available range of the location detector. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a position detection system for detecting the position of a mobile terminal such as a mobile phone.

  In recent years, with the spread and miniaturization of mobile terminals such as mobile phones, the loss of mobile terminals has also increased rapidly. The loss of a mobile terminal includes a temporary loss within a certain range such as in a house, or a loss that requires a wide range of searches such as misplacement.

  As an example of a simple search method (position detection method) used when a mobile terminal is lost within a certain range such as in a house, the mobile terminal being searched is called using another mobile terminal, A method of roughly grasping the position of the mobile terminal from the ring tone is often used. However, with this calling method, it is difficult to hear the ringtone of the mobile terminal, and it is not always easy to find the mobile terminal to be searched. In addition, when the setting for prohibiting the ringing of the ringtone is made, it is difficult to find the mobile terminal.

  In order to solve this problem, a mobile terminal search system that attempts to acquire the location information of a lost mobile terminal using a search device has been disclosed (for example, see Patent Document 1 below). In this mobile terminal search system, the search device is moved, and the location information of the mobile terminal to be searched is acquired from the positional relationship between the search device and the mobile terminal.

  Also, a search method using GPS (Global Positioning System) or a base station has been proposed for loss that requires a wide range of searches (see, for example, Patent Document 2 and Patent Document 3 below). When the location of a lost mobile terminal is identified using GPS or a base station, the presence or absence of the mobile terminal can be confirmed within a certain area.

JP 2003-32729 A JP 2004-23573 A JP 2003-284154 A

  However, in the search system described in Patent Document 1, it is necessary to carry the search device when searching. In addition, it is only possible to confirm whether or not the mobile terminal that is the search target is near the search device, and the location information of the mobile terminal that is the search target is used because the location information of the GPS or base station is used. It is difficult to acquire detailed position information.

  In addition, as in the above-mentioned Patent Document 2 and Patent Document 3, when a GPS or a base station is used for searching for a mobile terminal, the search area cannot be narrowed down. Cannot handle loss.

  An object of this invention is to provide the position detection system of the mobile terminal which can detect the position of the mobile terminal which is a to-be-detected object (search object) simply in view of said point.

  In order to achieve the above object, a mobile terminal position detection system according to the present invention is a mobile terminal position detection system comprising a mobile terminal and a position detection device that detects the position of the mobile terminal. Transmitting means for transmitting a call signal for detecting the position of the mobile terminal; receiving means capable of receiving a predetermined response signal to be returned from the mobile terminal in response to transmission of the call signal; and When the response signal corresponding to the transmission is not received by the receiving unit, a notification unit is provided for performing notification corresponding thereto.

  By referring to the notification by the notification means, it is possible to easily recognize whether or not the mobile terminal is within the range where the radio waves of the position detection device reach. For example, when the position detection device is in a certain house, it is possible to easily know whether or not the mobile terminal that is the position detection target (search target) is in the house.

  Specifically, for example, when the response signal corresponding to the transmission of the call signal is not received by the reception unit, the notification unit notifies that the mobile terminal is out of the communication range of the position detection device. To do.

  Further, for example, the position detecting device further includes a radio wave characteristic analyzing unit that analyzes a radio wave characteristic of the response signal received by the receiving unit, and the notifying unit is configured to use the mobile terminal based on the analyzed radio wave characteristic. The position information may be notified.

  Specifically, for example, the position information includes information representing a distance to the mobile terminal based on the position of the position detection device.

  Thereby, the distance between the mobile terminal that is the position detection target and the position detection device can be known, and the mobile terminal can be easily found.

  More specifically, for example, the position information includes information indicating the direction of the position of the mobile terminal with respect to the position of the position detection device.

  Thereby, it is possible to know in which direction the mobile terminal that is the position detection target is seen from the position detection device, and it is easy to find the mobile terminal.

  In addition, for example, the position detection device may register in advance the radio characteristics of a registration response signal transmitted from the mobile terminal in association with the specific position when the mobile terminal is at a specific position. And a comparison means for comparing the radio wave characteristic of the response signal for registration registered by the registration means and the radio wave characteristic of the response signal when the receiving means receives the response signal, The notification means may notify the position information of the mobile terminal based on the comparison result by the comparison means.

  For example, when the comparison means determines that the radio wave characteristic of the registration response signal matches the radio wave characteristic of the response signal, the notification means indicates that the mobile terminal is at the specific position. Inform you.

  This makes it easier to find a mobile terminal.

  For example, the installation location of the position detection device is substantially fixed.

  Thereby, the precision which detects whether the mobile terminal which is a position detection object exists in the said specific position improves.

  Further, for example, the position detection device may be provided in one-to-one correspondence with the mobile terminal.

  As a result, it is possible to omit the approval process by collation of the personal identification number and the like, and the possibility of erroneous approval is eliminated and the safety of information transmission is improved.

  As described above, according to the position detection system for a mobile terminal according to the present invention, the position of a mobile terminal that is a position detection target can be easily detected.

  Embodiments of a mobile terminal position detection system according to the present invention will be described below in detail with reference to the drawings. FIG. 1 is a diagram illustrating a state in which a position detection system according to an embodiment of the present invention is disposed indoors. FIG. 2 shows a block diagram of the position detection system of FIG. The position detection system shown in FIGS. 1 and 2 includes a mobile terminal 1 such as a mobile phone, and a position detection device 2 for detecting the position of the mobile terminal 1. The position detection system according to the present embodiment is used in a specific range such as in a house (indoor) as shown in FIG.

  The mobile terminal 1 receives a call signal from the position detection device 2, a response control unit 12 that performs a response process for the call signal, and a response signal that is controlled by the response control unit 12. And a transmission unit 13 for transmission. The mobile terminal 1 is, for example, a mobile phone, and includes a microphone, a speaker, a key input unit, and the like (all not shown) necessary as a mobile phone in addition to the parts shown in FIG.

  The position detecting device 2 analyzes a radio wave characteristic of the received response signal, a transmitting unit 21 for transmitting a call signal to the mobile terminal 1, a receiving unit 22 for receiving a response signal from the mobile terminal 1. A radio wave characteristic analysis unit 23, a registration processing unit (registration means) 24 for controlling a registration process performed in advance to detect the position of the mobile terminal 1, a semiconductor memory for recording contents registered by the registration process, and the like A registration content recording unit (registration means) 25, a comparison unit 26 that compares the registration content of the registration content recording unit 25 and the output content from the radio wave characteristic analysis unit 23, and a comparison result of the comparison unit 26. A display unit 27 for displaying information on the position of the mobile terminal 1 (hereinafter referred to as “position information”), an input unit 28 including buttons for accepting user operations and the like, and each part in the position detection device 2 are integrated. Controlled to configured to include a main control unit 29, a. The main control unit 29 includes a registration processing unit 24 and a comparison unit 26.

  In order to detect the position of the mobile terminal 1, registration processing is preferably performed in advance. FIG. 3 is an operation flowchart for explaining the registration process. First, the installation location of the position detection device 2 is fixed (step S1). “Fixing the installation location of the position detection device 2” means determining the installation location (installation position) of the position detection device 2 as a fixed location. At this time, not only the place but also the installation direction of the position detection device 2 is fixed. That is, once the registration process is performed, rotation of the position detection device 2 is prohibited until the registration process is performed again. This is because the position detection device 2 also detects the direction of the location of the mobile terminal 1 as viewed from the position detection device 2 as will be apparent from the following description.

  The “fixation” of the installation location and the installation direction does not necessarily mean complete fixation, but is a concept including that the position detection accuracy of the mobile terminal 1 fluctuates to an allowable level (position detection). The same applies to the case where the device 2 is built in an electrical device as described later). Therefore, in step S1, it can be said that the installation location and the installation direction of the position detection device 2 are “substantially fixed”.

  In step S2 following step S1, the mobile terminal 1 is placed at a specific position desired by the user. For example, it is placed indoors “on a Western-style chest (a specific part on a Western-style chest)”. Then, the user gives information representing the specific position to the main control unit 29 (registration processing unit 24) via the input unit 28 (step S3). For example, enter “on a Western-style room chest”.

  In step S4 following step S3, the main control unit 29 causes the transmission unit 21 to wirelessly transmit a registration call signal. The registration call signal is received by the receiving unit 11 of the mobile terminal 1 and transmitted to the response control unit 12. When receiving the registration call signal, the response control unit 12 controls the transmission unit 13 to wirelessly return a registration response signal from the transmission unit 13 (step S5).

  The registration response signal is received by the receiving unit 22. The radio wave characteristic analyzer 23 analyzes the radio wave characteristic of the registration response signal received by the receiver 22 (step S6). The radio wave characteristics of the registration response signal include the electric field strength of the received radio wave of the registration response signal (the electric field strength of the received radio wave) and the direction of the transmission source of the received radio wave (that is, the mobile terminal 1 viewed from the position detection device 2). Direction). When the position of the mobile terminal 1 arranged in step S2 is “on Western style chest”, the direction of the transmission source is “western style chest” or “western style chest” as viewed from the position detection device 2. ”.

  In step S7 following step S6, the registration processing unit 24 analyzes the radio wave characteristics of the response signal for registration analyzed by the radio wave characteristic analysis unit 23 (that is, the electric field strength of the received radio wave of the registration response signal and the transmission source of the received radio wave). Are registered in the registered content recording unit 25 together with the information indicating the specific position given in step S3. At this time, the radio wave characteristic of the registration response signal is recorded in association with the information representing the specific position.

  If there is no other information to be registered by the registration process, the registration process ends (Y in step S8). If there is other information to be registered, the process returns to step S2 and the above-described processing is repeated (N in step S8). For example, in step S <b> 2 again, the mobile terminal 1 is placed “on the TV in the living room (a specific part on the TV in the living room)”. Then, the user operates the input unit 28 to provide the main control unit 29 (registration processing unit 24) with information indicating the position “on the television in the living room” (steps S2 to S3). Thus, through steps S4 to S7, registration information corresponding to the fact that the mobile terminal 1 is “on the living room television” is recorded in the registration content recording unit 25.

  Next, a position detection method of the mobile terminal 1 by the position detection device 2 will be described. FIG. 4 is an operation flowchart for explaining this position detection method. However, for convenience of explanation, it is assumed that the registration process illustrated in FIG. 3 (FIG. 3) is performed before the operation illustrated in FIG. That is, the mobile terminal 1 is placed on the “western chest (specific portion on the western chest)” and the processing of FIG. 3 (particularly, the processing in steps S3 to S7) has already been performed. And In addition, the radio characteristics of the response signal for registration recorded in the registration content recording unit 25 in a state where the mobile terminal 1 is placed on “the chest of the Western-style room (a specific part on the chest of the Western-style room)” A ".

  First, in step S11, it is determined whether or not a position detection command for detecting the position of the mobile terminal 1 has been input to the input unit 28. When this position detection command is input (Y in step S11), the main control unit 29 causes the transmission unit 21 to wirelessly transmit a position detection calling signal (step S12). The transmitted position detection calling signal is received by the receiving unit 11 of the mobile terminal 1 and transmitted to the response control unit 12. If no position detection command is input (Y in step S11), the process in step S11 is repeated.

  When the response control unit 12 receives the position detection calling signal, the response control unit 12 controls the transmission unit 13 to wirelessly return the position detection response signal from the transmission unit 13 (step S13). The transmission radio waves of the position detection response signal and the registration response signal transmitted in step S5 in FIG. 3 have, for example, the same electric field strength.

  In step S14 following step S13, it is determined whether or not the position detection response signal has been received by the receiving unit 22. This determination is performed by, for example, the radio wave characteristic analysis unit 23 and / or the main control unit 29. If a position detection response signal is received, the process proceeds to step S15 described later (Y in step S14). If a position detection response signal is not received, the process proceeds to step S17 described later (N in step S14). ).

  When the mobile terminal 1 is outside the communicable range of the position detection device 2, that is, the mobile terminal 1 is close to the position detection device 2 to the extent that wireless communication is possible between the mobile terminal 1 and the position detection device 2. When not positioned, the position detection response signal is not received. Also, when the mobile terminal 1 is turned off (power supply is cut off), the position detection response signal is not received.

  In step S <b> 15, the radio wave characteristic analysis unit 23 analyzes the radio wave characteristic of the position detection response signal received by the reception unit 22. The radio wave characteristics of the position detection response signal include the electric field strength of the received radio wave of the position detection response signal (the electric field strength of the received radio wave) and the direction of the transmission source of the received radio wave (that is, movement viewed from the position detection device 2). Including the direction of the terminal 1).

  In step S16 following step S15, the radio wave characteristics (the electric field strength of the received radio wave and the direction of the transmission source of the received radio wave) of the analyzed position detection response signal are recorded in the registration content recording unit 25 by the comparison unit 26. Compared with the registered radio wave characteristics. As described above, the registration content recording unit 25 records the registered radio wave characteristic A corresponding to the fact that the mobile terminal 1 is placed on “the chest of the Western-style room (a specific part on the chest of the Western-style room)”. However, if there are other registered radio wave characteristics, the radio wave characteristics of the position detection response signal are compared for each registered radio wave characteristic.

  Based on the comparison result in step S16, the position information of the mobile terminal 1 is displayed on the display unit 27 in step S17, and the operation shown in FIG. 4 ends. The location information of the mobile terminal 1 notified (displayed) by the display unit 27 is mainly classified into three types.

  First, the first type of notification (display) is performed when either the radio wave characteristic of the position detection response signal matches the registered radio wave characteristic. When the position of the mobile terminal 1 at the time of position detection is “on the chest of the Western-style room (a specific part on the chest of the Western-style room)”, the field strength of the received radio wave of the analyzed response signal for position detection and the transmission of the received radio wave The original directions coincide with those in the registered radio wave characteristic A. Therefore, in this case, information indicating the specific position (that is, on the chest of the Western-style room) recorded in association with the registered radio wave characteristic A is displayed as the first type of notification.

  The second type of notification (display) is performed when the radio wave characteristic of the position detection response signal does not match any of the registered radio wave characteristics (however, the position detection response signal is received). As the second type of notification, for example, distance information to the mobile terminal 1 and / or direction information of the mobile terminal 1 are displayed.

  The “distance information to the mobile terminal 1” in the second type of notification is information representing the distance to the mobile terminal 1 based on the installation location (position) of the position detection device 2, in other words, the position This is information representing the distance between the detection device 2 and the mobile terminal 1. The electric field intensity of the transmission radio wave of the position detection response signal (the electric field intensity of the radio wave to be transmitted) is predetermined, and the distance between the position detection device 2 and the mobile terminal 1 and the electric field intensity of the reception radio wave of the position detection response signal. Is recorded in advance in the registration content recording unit 25 or a memory (not shown). The main control unit 29 (comparison unit 26) calculates “distance information to the mobile terminal 1” based on the correlation, and causes the display unit 27 to display the “distance information to the mobile terminal 1”.

  Any display may be performed as long as the user can confirm the distance to the mobile terminal 1. For example, a display such as “the distance to the mobile terminal 1 is about 5 meters”, “the distance to the mobile terminal 1 is about 5 to about 10 meters”, etc., or reception of a position detection response signal The electric field strength of radio waves may be displayed directly.

  The “direction information of the mobile terminal 1” in the second type of notification is information indicating the direction (direction) of the location of the mobile terminal 1 viewed from the position detection device 2, in other words, the position detection device 2. This is information indicating the direction (direction) of the location of the mobile terminal 1 with reference to the installation location (position). Any display may be performed as long as the user can check the direction in which the mobile terminal 1 is located. For example, “direction information of the mobile terminal 1” may be displayed using the directions of east, west, south, and north, or an arrow indicating the direction in which the mobile terminal 1 is located may be displayed.

  The third type of notification (display) is performed when the position detection response signal is not received, that is, when the determination result in step S14 is negative (N in step S14). As the third type of notification, the display unit 27 displays a content indicating that “the mobile terminal 1 is outside the communicable range of the position detection device 2” or “the mobile terminal 1 is turned off”. The

  The position detection system shown in FIG. 2 notifies the position information of the mobile terminal 1 by display on the display unit 27 (although the first to third types of notification are realized), a speaker (not shown) The position information may be notified using sound emission by a vibration or vibration by a vibrator (not shown). That is, any notifying means such as visual, auditory, and sensory may be employed for notifying the location information of the mobile terminal 1.

  After the registration process shown in FIG. 3, it is desirable that the installation location and the installation direction of the position detection device 2 are fixed (substantially fixed). Also, it is desirable that power for realizing the operation shown in FIG. Furthermore, it is desirable that the position detection device 2 is provided in one-to-one correspondence with the mobile terminal 1 such as a charger (not shown) of the mobile terminal 1. That is, it is desirable that one mobile terminal 1 and one position detection device 2 have a paired relationship.

  When the mobile terminal 1 receives the call signal (registration call signal and / or position detection call signal), the response signal (registration response signal and / or position) is not performed without authenticating the source of the call signal. Returning the detection response signal) is not preferable from the viewpoint of safety. Considering this point, “the identification signal such as a personal identification number is included in the call signal, and the identification information and the identification information registered in the recording means (not shown) of the mobile terminal 1 are collated (approval processing). In the above configuration, the response signal is returned. However, as described above, if the mobile terminal 1 and the position detection device 2 have a one-to-one correspondence, the collation can be omitted and erroneous collation is not performed. Improves.

  However, if it is an electrical device that is always in a fixed position, such as a television receiver, fixed telephone, desktop personal computer (not shown), indoors, etc. The apparatus 2 may be introduced. That is, the position detection device 2 may be attached to an arbitrary electric device whose installation location and installation direction are fixed (substantially fixed). You may incorporate the position detection apparatus 2 in those electric devices.

  FIG. 5 is a block diagram showing the configuration of the position detection device 2. The response signal (registration response signal and / or position detection response signal) sent from the mobile terminal 1 is received by the antenna unit 41. A signal received by the antenna unit 41 is sent to a receiving circuit 43 via a DUP (antenna sharing unit) 42, and the received information is sent to a baseband signal processing unit 45. The baseband signal processing unit 45 is provided with a central processing unit (CPU) 46 that is a control center and a memory 47 that is accessed by the CPU 46. Reference numeral 48 denotes a display unit that displays various types of information, and 49 denotes an input unit (operation unit) for performing various operations on the position detection device 2, and these are types of baseband signals (bases such as a display system or an operation system). A process determined according to the type of the band signal is executed. The microphone 50 and the speaker 51 perform processing by sound.

  Reference numeral 44 denotes a transmission circuit for transmitting a calling signal (registration calling signal and / or position detection calling signal). The calling signal is transmitted from the antenna unit 41 via the DUP 42. A local oscillation signal necessary for signal processing is supplied from the oscillator 52 to each of the reception circuit 43 and the transmission circuit 44.

  2 mainly includes the antenna unit 41, the DUP 42, and the transmission circuit 44 shown in FIG. 2 mainly includes the antenna unit 41, the DUP 42, and the receiving circuit 43 shown in FIG. The radio wave characteristic analysis unit 23 in FIG. 2 mainly includes a baseband signal processing unit 45, a CPU 46, and a memory 47 in FIG. The main control unit 29 in FIG. 2 mainly includes the CPU 46 in FIG. The registration content recording unit 25 in FIG. 2 is provided in the memory 47 of FIG. The display unit 27 in FIG. 2 corresponds to the display unit 48 in FIG. 5, and the input unit 28 in FIG. 2 corresponds to the input unit 49 in FIG.

  In the radio wave characteristic analysis unit 23, it is possible to analyze the direction of the transmission source of the response signal (registration response signal and / or position detection response signal), that is, the direction of the mobile terminal 1 as viewed from the position detection device 2. The antenna unit 41 includes a plurality of antennas having directivity. For example, the antenna unit 41 includes an 8-shaped directivity that exhibits relatively high sensitivity in the front and rear directions, and a first antenna having a single directivity that exhibits relatively high sensitivity only in one direction, a second antenna, , And n-th antenna (n is an integer of 2 or more), and the first, second,..., And n-th antennas have high sensitivity directions (directions in which the sensitivity is highest). It is being fixed to the position detection apparatus 2 so that it may mutually differ. The direction of the mobile terminal 1 viewed from the position detection device 2 is analyzed based on the intensity of the signal received by each of the first to nth antennas.

  In addition to the first to nth antennas, a non-directional antenna may be provided in the antenna unit 41. Information on the intensity of the signal received by the omnidirectional antenna is used for calculating the distance between the position detection device 2 and the mobile terminal 1 and also for analyzing the direction of the mobile terminal 1 viewed from the position detection device 2. Used.

  It is not always necessary to perform the registration process shown in FIG. However, when this registration process is not performed in advance, the above-described first type of notification is not performed.

  For convenience of explanation, the call signal for registration processing is called a registration call signal, and the call signal for position detection is called a position detection call signal, but these signals are the same. . However, they may be different signals. Similarly, for convenience of explanation, the response signal at the time of registration processing is called a response signal for registration, and the response signal at the time of position detection is called a response signal for position detection, but these are the same signals. is there. However, they may be different signals.

  The mobile terminal 1 is not limited to a mobile phone. For example, portable devices such as portable music playback devices, small computers, etc., all of the electrical devices that are not defined and that may be lost within a specific range such as indoors are stored in the mobile terminal 1. Can be.

  According to the position detection system for a mobile terminal according to the present invention, the position of a mobile terminal that is a position detection target can be easily detected.

It is a figure showing a mode that the position detection system which concerns on embodiment of this invention is arrange | positioned indoors. It is a figure which shows the block block diagram of the position detection system of FIG. It is a flowchart which shows the registration processing operation | movement by the position detection apparatus of FIG. It is a flowchart which shows the position detection operation | movement by the position detection apparatus of FIG. The block diagram which shows the structure of the position detection apparatus of FIG. 2 is shown.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Mobile terminal 11 Reception part 12 Response control part 13 Transmission part 2 Position detection apparatus 21 Transmission part 22 Reception part 23 Radio wave characteristic analysis part 24 Registration processing part 25 Registration content recording part 26 Comparison part 27 Display part 28 Input part 29 Main control part 41 Antenna part 42 DUP (antenna common part)
43 Receiving Circuit 44 Transmitting Circuit 45 Baseband Signal Processing Unit 46 CPU
47 Memory 48 Display unit 49 Input unit 50 Microphone 51 Speaker 52 Oscillator

Claims (9)

In a mobile terminal position detection system comprising a mobile terminal and a position detection device that detects the position of the mobile terminal, the position detection device comprises:
Transmitting means for transmitting a call signal for position detection of the mobile terminal;
Receiving means capable of receiving a predetermined response signal to be returned from the mobile terminal in response to transmission of the calling signal;
A position detection system for a mobile terminal, comprising: notification means for performing notification corresponding to the response signal corresponding to transmission of the calling signal when the response signal is not received by the reception means. The informing means informs that the mobile terminal is out of a communicable range of the position detecting device when the response signal corresponding to the transmission of the calling signal is not received by the receiving means. Item 2. The mobile terminal position detection system according to Item 1. The position detecting device further includes radio wave characteristic analyzing means for analyzing the radio wave characteristic of the response signal received by the receiving means,
The mobile terminal position detection system according to claim 1 or 2, wherein the notification means notifies the mobile terminal of positional information based on the analyzed radio wave characteristics. 4. The position detection system for a mobile terminal according to claim 3, wherein the position information includes information representing a distance to the mobile terminal based on a position of the position detection device. The position of the mobile terminal according to claim 3 or 4, wherein the position information includes information indicating a direction of the position of the mobile terminal with respect to the position of the position detection device. Detection system. The position detection device includes:
Registration means for pre-registering the radio characteristics of a response signal for registration transmitted from the mobile terminal when the mobile terminal is at a specific position in association with the specific position;
Comparing means for comparing the radio wave characteristic of the response signal for registration registered by the registration means with the radio wave characteristic of the response signal when the receiving means receives the response signal;
The position detection system for a mobile terminal according to claim 1 or 2, wherein the notification means notifies position information of the mobile terminal based on a comparison result by the comparison means. When the comparing means determines that the radio wave characteristic of the registration response signal matches the radio wave characteristic of the response signal, the notifying means notifies that the mobile terminal is at the specific position. The position detection system for a mobile terminal according to claim 6. The position detection system of the mobile terminal according to claim 6 or 7, wherein an installation place of the position detection device is substantially fixed. The position detection system for a mobile terminal according to any one of claims 1 to 8, wherein the position detection device is provided in one-to-one correspondence with the mobile terminal.

Images