JP5355139B2 - Terminal position estimation system, terminal position estimation apparatus, wireless terminal apparatus, and terminal position estimation method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a system or the like that enhances the accuracy of position estimation in a radio terminal device. <P>SOLUTION: The radio base station devices A1 to AM includes an incoming direction estimation unit T1 which estimates the incoming direction of radio wave from a radio signal of a radio terminal device B1 which each of a plurality of antennas is received. The terminal position estimating device D1 consists of a memory and a terminal position estimation unit. The memory memorizes beforehand the direction of the incoming radio wave into each of the radio base station devices A1 to AM and the position of reference point, from the reference point, for each of the plurality of the reference points showing the positions. The terminal position estimation unit estimates the position of the radio terminal device B1 based on the difference of the radio wave incoming direction into each of radio base station devices A1 to AM, from the reference point which is read from the memory and each estimated radio wave incoming direction by the plurality of radio base station devices A1 to AM. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a terminal position estimation system, a terminal position estimation apparatus, a radio terminal apparatus, and a terminal position estimation method that estimate the position of a radio terminal by estimating the arrival direction of radio waves between the radio terminal and a plurality of base stations.

FIG. 10 is a block diagram illustrating a configuration of a wireless device (terminal position estimation system) according to the technology that is the background of the present invention. In the terminal position estimation method by the wireless device shown in this figure, in a wireless device equipped with a plurality of wireless base station devices A0-1 to A0-M and one or more wireless terminal devices B0, a plurality of wireless terminals are transmitted from the wireless terminal device B0. The position of the wireless terminal device B0 is estimated by estimating the arrival directions of radio waves to the base stations A0-1 to A0-M.
In this case, each of the radio base station apparatuses A0-1 to A0-M includes a plurality of reception antennas # 1 to #N _i (i = 1, 2,..., M), a radio unit R0, and an arrival direction estimation unit T0. Equipped. Each of the radio base station apparatuses A0-1 to A0-M estimates the arrival direction of the radio wave by the arrival direction estimation unit T0, and the arrival direction estimation line l from the coordinates of the radio base station apparatuses A0-1 to A0-M. _{1 to 1 M} are determined. Then, the terminal position estimating unit D0 is, determine the position of the wireless terminal device B0 from the arrival direction estimation linear _l 1 to l _M. Specifically, when there are two radio base station apparatuses, the coordinates of the intersections of the arrival direction estimation straight lines l ₁ and l ₂ calculated by the respective radio base station apparatuses A0-1 and A0-2 are used as the position of the radio terminal apparatus B0. And When there are three or more radio base station apparatuses, there are a plurality of intersections of the respective arrival direction estimation straight lines l _{1 to} l _M. Therefore, the terminal position estimation unit D0 sets the coordinates obtained by geometrically averaging the intersections to the radio terminal. The position is the position of the device B0 (for example, see Non-Patent Document 1). Alternatively, the terminal position estimation unit D0 normalizes the equations of the arrival direction estimation straight lines, and sets the solution obtained by the pseudo inverse matrix calculation as the position of the wireless terminal device B0 (for example, see Non-Patent Document 2).

FIG. 11 is a block diagram showing another configuration of the wireless device (terminal position estimation system) according to the technology that is the background of the present invention. In the wireless device shown in this figure, the wireless terminal device B0-1 includes a plurality of receiving antennas # 1 to #L, a wireless unit R′0, an arrival direction estimating unit T′0, and a terminal position estimating unit D′ 0. doing. The radio terminal apparatus B0-1 estimates the arrival directions of the radio waves from the radio base station apparatuses S0-1 to S0-M by the arrival direction estimation unit T′0, and each radio base station apparatus S0-1 to S0-1 The direction-of-arrival estimation straight lines l ′ _{1 to} l ′ _M are determined from the coordinates of S0-M. Then, the terminal position estimating unit D'0 is, determine the position of the wireless terminal device B0-1 from the arrival direction estimation linear l _'1 ~l' _M. The method of estimating the position of the wireless terminal device B0-1 from the arrival direction estimation straight lines l ′ _{1 to} l ′ _M is the same as that of the prior art shown in FIG.

Jun Terada, Takahashi, H. Sato, Y. Mutoh, S. “A novel location-estimation method using direction-of-arrival estimation,” Vehicular Technology Conference, 2005. VTC-2005-Fall. 2005 IEEE 62nd, 28-25 Sept., 2005 Volume: 1, On page (s): 424-428 Ben Noble, James W. Danie “Applied Linear Algebra,” Prentice Hall; 3 edition (November 11, 1987)

  However, in the conventional techniques as shown in Non-Patent Documents 1 and 2 described above, the power of the radio signal transmitted from the radio terminal apparatus is low in a radio propagation environment, particularly in a place far away from the radio base station apparatus. As a result, the influence of noise increases and the estimation error of the arrival direction of the radio signal increases. Therefore, in such an environment, the reliability of the arrival direction estimation line calculated by each radio base station apparatus is different, and the reliability is low when estimating the position of the radio terminal apparatus from each arrival direction estimation line. There is a problem that the estimation accuracy deteriorates due to the influence of the arrival direction estimation straight line.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a terminal position estimation system, a terminal position estimation apparatus, a wireless terminal apparatus, and a terminal position estimation method capable of improving the position estimation accuracy of the wireless terminal apparatus. Is to provide.

(1) The present invention has been made to solve the above problems, and one aspect of the present invention includes a plurality of reception antennas, a radio base station apparatus and a radio terminal apparatus received by each of the plurality of reception antennas. Based on the arrival direction estimation unit that estimates the arrival direction of radio waves from wireless signals transmitted to and received from each other, and the coordinate values of each of a plurality of wireless base station devices and the coordinate values of a plurality of reference points that represent positions Then, for each reference point, a geometric database creation unit that geometrically calculates the direction of radio waves determined by the positional relationship between the reference point and the radio base station apparatus, and for each reference point, the geometric in association with the direction of the radio wave which is calculated by the specific database creation unit to the position of the reference point, and the geometric database for storing in advance, electricity which the arrival direction estimation unit has estimated Terminal position and direction of arrival, comprising: a, a terminal position estimating unit that estimates a position of the wireless terminal device based on the radio wave direction and position of each of the reference points read from the geometric database It is an estimation system.

(2) Moreover, one aspect of the present invention includes a plurality of receiving antennas, and an arrival direction estimating unit that estimates an arrival direction of a radio wave from a radio signal received from each of the plurality of receiving antennas. A plurality of radio base station devices, and a coordinate value of each of the plurality of radio base station devices and a coordinate value of a plurality of reference points representing a position, for each reference point, from each of the reference points geometric database creation unit that the calculating the arrival direction of the radio wave to the radio base station apparatus geometrically in, for each of the reference points, the arrival direction of the radio wave which is calculated by the geometric database creation unit in association with the position of the reference point, and the geometric database for storing in advance, the geometry and the incoming direction of the radio wave by the plurality of radio base station apparatus estimated respectively Anda terminal position estimating unit that estimates a position of the wireless terminal device based on the difference between the arrival direction of radio waves to each of the radio base station apparatus from the reference point read from the database, the radio base station A terminal position estimation system comprising: a terminal position measuring apparatus installed in the apparatus or independently of the radio base station apparatus.

(3) In addition, according to one aspect of the present invention, in the terminal position estimation system, the terminal position estimation unit may receive a radio wave from the reference point read from the geometric database to the radio base station apparatus. And the square of the angle difference with the arrival direction of the radio wave estimated by the radio base station apparatus is calculated for all the radio base station apparatuses, and the reference point with the smallest sum of the squares of the calculated angle differences is calculated. It is set as the position of the said radio | wireless terminal apparatus.

(4) One embodiment of the present invention includes a step of estimating an arrival direction of a radio wave from a radio signal transmitted and received between a radio base station apparatus and a radio terminal apparatus received by each of a plurality of reception antennas , Based on the coordinate values of each of the radio base station devices and the coordinate values of a plurality of reference points representing the positions, for each reference point, the radio wave determined by the positional relationship between the reference point and the radio base station device A step of geometrically calculating a direction ; a step of storing the direction of the radio wave calculated in the step of calculating for each reference point in advance in a geometric database in association with the position of the reference point ; an arrival direction of the radio wave estimated in the step of estimating an arrival direction of the radio wave, radio wave for each of the reference points read from the geometric database A terminal position estimating method characterized by comprising the steps of estimating a location of the wireless terminal device based on the direction and position, the.

(5) Further, according to one aspect of the present invention, the radio base station apparatus estimates a radio wave arrival direction from radio signals from radio terminal apparatuses received by each of the plurality of receiving antennas; Alternatively, the terminal position measurement device installed independently of the radio base station device is based on the coordinate values of a plurality of radio base station devices and the coordinate values of a plurality of reference points representing positions. for each point, a step of geometrically calculates the arrival direction of radio waves to each of the radio base station apparatus from the reference point, for each of the reference point, the direction of arrival of the radio wave calculated in the step of calculating in association with the position of the reference point, and storing in advance a geometric database, arrival direction of radio waves in which a plurality of the radio base station apparatus estimated respectively When, characterized in that it has the steps of estimating a location of the wireless terminal device based on the difference between the arrival direction of radio waves from the reference point read from the geometric database to each of the radio base station apparatus Is a terminal position estimation method.

(6) Further, according to one aspect of the present invention, in the terminal position estimation method described above, a radio wave arrival direction from the reference point read from the geometric database to the radio base station apparatus, and the radio base station apparatus Is calculated for all the radio base station devices, and the reference point having the smallest sum of the squares of the calculated angle differences is the position of the radio terminal device. It is characterized by doing.

(7) Further, according to one aspect of the present invention, a plurality of radio base station apparatuses that have a plurality of reception antennas and estimate the arrival directions of radio waves from radio signals from radio terminal apparatuses received by the plurality of reception antennas. For each reference point, based on the receiving unit that receives the direction of arrival of the radio wave estimated from, and the coordinate values of the plurality of wireless base station devices and the coordinate values of the plurality of reference points that represent positions A geometric database creation unit that geometrically calculates the direction of arrival of radio waves from the reference points to the radio base station devices, and the geometric database creation unit that calculates the reference points for each reference point. in association with the arrival direction of the radio wave at the position of the reference point, and the geometric database for storing in advance, the radio waves of the plurality of radio base station apparatus estimated respectively A terminal position estimating section for estimating the position of the wireless terminal device based on the direction of arrival read from the geometric database the reference point to the difference between the arrival direction of radio waves to each of the radio base station apparatus, the And a terminal position measuring apparatus installed in the radio base station apparatus or independently of the radio base station apparatus.

(8) Further, according to one aspect of the present invention, in the terminal position measurement apparatus, the terminal position estimation unit may receive a radio wave from the reference point read from the geometric database to the radio base station apparatus. And the square of the angle difference with the arrival direction of the radio wave estimated by the radio base station apparatus is calculated for all the radio base station apparatuses, and the reference point with the smallest sum of the squares of the calculated angle differences is calculated. It is set as the position of the said radio | wireless terminal apparatus.

(9) One aspect of the present invention is a terminal position estimation system including a wireless terminal device having a plurality of reception antennas and a plurality of wireless base station devices that transmit wireless signals to the wireless terminal device, the wireless terminal device, an arrival direction estimation unit that estimates an arrival direction of a radio wave from the radio signal from each of said radio base station device from said plurality of receiving antennas of the plurality of radio base station apparatuses each of which receives the plurality On the basis of the respective coordinate values of each of the plurality of wireless base station devices and the coordinate values of the plurality of reference points representing the positions, radio waves from each of the plurality of wireless base station devices to the reference point for each reference point. geometric database creation unit which calculates the arrival direction geometrically, for each of the reference points, the radio wave which is calculated by the geometric database creation unit Associates come direction to the position of the reference point, and the geometric database for storing in advance, reads the incoming direction of the radio wave from each of the arrival direction estimation unit has estimated the radio base station apparatus from the geometric database And a terminal position estimation unit that estimates the position of the own apparatus based on a difference from the arrival direction of the radio wave from each radio base station apparatus to the reference point. .

(10) In addition, according to one aspect of the present invention, in the terminal position estimation system, the terminal position estimation unit may receive a radio wave from the radio base station apparatus read from the geometric database to the reference point. And the square of the angle difference with the arrival direction of the radio wave from the radio base station apparatus estimated by the arrival direction estimation unit is calculated for all the radio base station apparatuses, and the sum of the squares of the calculated angle differences The reference point having the smallest value is the position of its own device.

(11) Further, an embodiment of the present invention, non-linear terminal device, the direction of arrival of radio waves from each of the radio base station apparatus from a radio signal from the plurality of radio base station apparatus each of a plurality of receiving antennas receives From each of the plurality of radio base station devices for each reference point based on the estimating step and the coordinate values of each of the plurality of radio base station devices and the coordinate values of the plurality of reference points representing positions. Geometrically calculating the direction of arrival of radio waves at the reference point; and for each reference point, the direction of arrival of radio waves calculated in the calculating step is associated with the position of the reference point in advance, and storing the biological database, arrival direction of radio waves from each of the radio base station apparatus estimated in the step of estimating the direction of arrival of the radio wave Terminal and having the steps of: estimating a position of the own apparatus based on the difference between the radio wave arrival direction to the reference point from the geometric each of the radio base station apparatus read from the database and This is a position estimation method.

(12) Further, according to one aspect of the present invention, in the terminal position estimation method described above, an arrival direction of a radio wave from the radio base station apparatus read from the geometric database to the reference point and the estimated radio base The square of the angle difference from the arrival direction of the radio wave from the station device is calculated for all the radio base station devices, and the reference point having the smallest sum of the squares of the calculated angle difference is set as the position of the own device. It is characterized by that.

(13) In addition, according to one embodiment of the present invention, a plurality of reception antennas and arrival directions of radio waves from the radio base station devices from radio signals from the radio base station devices received by the plurality of reception antennas. And each of the plurality of radio base stations for each reference point based on the arrival direction estimation unit for estimating the coordinate values of each of the plurality of radio base station devices and the coordinate values of the plurality of reference points representing positions. geometric database creation unit for geometrically calculates the arrival direction of the radio wave to the reference point from the station unit respectively, for each of the reference point, the direction of arrival of the radio wave which is calculated by the geometric database creation unit in association with the position of the reference point, and the geometric database for storing in advance, the radio base station apparatus or each of said arrival direction estimation unit estimates Each of said terminal position estimating unit that estimates a position of the own apparatus based on the difference from the radio base station apparatus and the arrival direction of the radio wave to the reference point and the arrival direction of the radio wave is read from the geometric database, A wireless terminal device.

(14) Further, according to one aspect of the present invention, in the above wireless terminal device, the terminal position estimation unit includes an arrival direction of the radio wave from the wireless base station device read from the geometric database to the reference point. The square of the difference in angle with the arrival direction of the radio wave from the radio base station apparatus estimated by the arrival direction estimation unit is calculated for all the radio base station apparatuses, and the sum of the squares of the calculated difference in angle is The smallest reference point is the position of the own device.

According to the present invention, the position of the wireless terminal device is estimated based on the direction and position of the radio wave for each reference point stored in the storage unit and the estimated arrival direction of the radio wave. The wireless terminal position can be estimated based on the reliability, and the terminal position estimation accuracy can be improved.
In addition, since the reference point with the smallest square sum of the angle difference of the arrival directions is set as the position of the wireless terminal device, the arrival direction of the wireless base station device located closer to the wireless terminal device is given priority. That is, the reliability of the arrival direction of the radio base station apparatus located closer to the radio terminal apparatus is increased. As a result, the position of the wireless terminal device can be estimated with priority given to the estimated arrival directions that are less affected by noise, and therefore the position estimation accuracy of the wireless terminal device can be improved.

It is a block diagram which shows the structure of the radio | wireless apparatus (terminal position estimation system) by the 1st Embodiment of this invention. It is the schematic for demonstrating the angle of arrival and reference point by this embodiment. It is a block diagram which shows the function structure of the terminal position estimation apparatus by this embodiment. It is the schematic which shows the data structure and data example of a reference table which the geometric database by this embodiment memorize | stores. It is the schematic for demonstrating the terminal location estimation process by this embodiment. It is a block diagram which shows the structure of the radio | wireless apparatus (terminal position estimation system) by 2nd Embodiment. It is the schematic for demonstrating the angle of arrival and reference point by this embodiment. It is a block diagram which shows the function structure of the radio | wireless terminal apparatus by this embodiment. It is the schematic which shows the data structure and data example of a reference table which the geometric database by this embodiment memorize | stores. It is a block diagram which shows the structure of the radio | wireless apparatus (terminal position estimation system) by the technique used as the background of this invention. It is a block diagram which shows the other structure of the radio | wireless apparatus (terminal position estimation system) by the technique used as the background of this invention.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.
[First Embodiment]
FIG. 1 is a block diagram showing a configuration of a wireless device (terminal position estimation system) according to the first embodiment of the present invention. The radio apparatus shown in FIG. 1 includes a plurality of radio base station apparatuses A1 to AM, a terminal location estimation apparatus D1 connected to each radio base station apparatus A1 to AM through a predetermined communication line, and one or a plurality of radio terminal apparatuses. B1 (only one unit is shown in FIG. 1). Each of the wireless base station devices A1 to AM and the wireless terminal device B1 perform wireless communication. Here, for convenience of explanation, the i-th radio base station apparatuses A1 to AM are hereinafter referred to as radio base station apparatuses Ai (i = 1, 2,..., M). In this embodiment, the terminal position estimation device D1 is a device independent of the radio base station devices A1 to AM and the radio terminal device B1, but the function is provided in any one of the radio base station devices A1 to AM. May be.

In Figure 1, the radio base station apparatus Ai (1 ≦ i ≦ M) includes a plurality of receiving antennas # 1 to # _{N i,} a radio unit R1 for transmitting and receiving radio signals, a plurality of receiving antennas # 1 to # through N _i equipped with DOA estimation portion T1 for estimating the arrival direction of the radio wave from the radio signal from the wireless terminal device B1 received by the wireless unit R1, is located some distance from each other. Receiving antenna # 1~ # N _i constitute the array antenna are arranged in an array.

In addition, the arrival direction estimation unit T1 in the present embodiment uses CMA (Constant Modulus Algorithm) as an arrival direction estimation method. In CMA, the arrival direction of radio waves is calculated based on the property that the envelope of a desired signal is constant. Specifically, first, the arrival direction estimation unit T1 is the evaluation function Q Q = E a ^{[|| y | q | p -σ} p]. Here, E [•] is an ensemble average, y = w ^T x, and ^T represents transposition. In addition, w = [w1, w2, ... wN i] is a ^{T, x = [x1, x2} , ..., xN i] is a ^T. wj is the weight of the j-th receive antenna # 1~ # _{N i,} xj is the symbol of the radio signal received by the j-th receive antenna # 1~ # _{N i.} Weight and is the weight in the synthesis of the received signals of each receiving antenna # 1~ # N _i. σ is the envelope value of the desired signal. Next, the arrival direction estimation unit T1, using the steepest gradient method or Marquardt, as the evaluation function is minimized to determine the weights wj of the receiving antennas # 1~ # N _i. Then, the arrival direction estimation unit T1 obtains the angle of the peak value in the antenna directivity pattern based on the weight wj (1 ≦ j ≦ N _i ), and sets this angle as the arrival direction of the radio wave.
In this embodiment, CMA is used as the direction of arrival estimation method. However, any method for estimating the direction of arrival using a plurality of antennas such as MMSE (Minimum Mean Square Error) and MUSIC (Multiple Signal Classification) methods can be used. It may be used.

  Each of the radio base station apparatuses A1 to AM receives the radio signal transmitted from the radio terminal apparatus B1, and estimates the arrival direction of the radio wave by each arrival direction estimation unit T1. And each wireless base station apparatus A1-AM transmits the estimated arrival direction to the terminal position estimation apparatus D1. The terminal position estimation device D1 estimates the position of the wireless terminal device B1 based on the arrival directions received from the wireless base station devices A1 to AM.

FIG. 2 is a schematic diagram for explaining the angle of arrival and the reference point according to the present embodiment. As shown in FIG. 2, an XY coordinate system is defined with a predetermined direction as an X-axis direction and a direction orthogonal to the X-axis direction as a Y-axis direction. Further, R reference points r (r = 1, 2,..., R) are provided in an area in which radio communication with the radio base station apparatuses A1 to AM is possible. Further, the XY coordinate value of the reference point r is defined as (x _r , y _r ), and the angle of the arrival direction of the radio wave from the reference point r to the radio base station apparatus Ai with respect to the X-axis direction is defined as the arrival angle θ _ir . . The arrival angle θ _ir is the direction of the radio wave determined by the positional relationship between the reference point r and the radio base station apparatus Ai.

FIG. 3 is a block diagram showing a functional configuration of the terminal position estimation apparatus D1 according to the present embodiment. The terminal position estimation device D1 includes an estimated arrival angle reception unit D11, a terminal position estimation unit D12, a geometric database C, and a geometric database creation unit C1.
The estimated arrival angle receiving unit D11 receives each estimated arrival angle φ _i from the radio base station apparatuses A1 to AM, and outputs the received estimated arrival angle φ _i to the terminal position estimation unit D12. The estimated arrival angle φ _i is an angle of the arrival direction of the radio wave estimated by the radio base station apparatuses A1 to AM with respect to the X-axis direction.
The geometric database C (storage unit) stores the XY coordinate value and the angle of arrival θ of the reference point r for each of the plurality of reference points r representing a predetermined position in the area where the radio base station apparatuses A1 to AM can communicate with each other. _ir (the direction of arrival of radio waves from the reference point r to each of the radio base station apparatuses A1 to AM) is stored. Data stored in the geometric database C will be described later.
The terminal position estimation unit D12 estimates the position of the wireless terminal device B1 based on the difference between the input estimated arrival angle φ _i and the arrival angle θ _ir read from the geometric database C. Detailed processing of the terminal position estimation unit D12 will be described later.
The geometric database creation unit C1 geometrically calculates the arrival angle θ _ir based on the XY coordinate values of the radio base station apparatuses A1 to AM and the XY coordinate value of the reference point r, and stores them in the geometric database C. Store. Note that the XY coordinate values of the radio base station apparatuses A1 to AM and the XY coordinate value of the reference point r are set in advance in the terminal position estimation apparatus D1.

FIG. 4 is a schematic diagram illustrating a data structure and an example of a reference table stored in the geometric database C according to the present embodiment. As shown in the figure, the reference table is two-dimensional tabular data composed of rows and columns, and has columns for each item of reference points and angles of arrival at the base station. Each row of this table exists for each reference point. The reference point data (item) holds the XY coordinate values (x _r , y _r ) of the reference point r. The arrival angle at the base station is the arrival angle θ _ir of radio waves from the reference point r to each radio base station apparatus Ai.

Next, terminal position estimation processing by the terminal position estimation unit D12 will be described with reference to FIG. FIG. 5 is a schematic diagram for explaining terminal position estimation processing according to the present embodiment. The terminal position estimation unit D12 first calculates the evaluation value Er of each reference point according to the following equation (1). Then, the XY coordinate value (x _r , y _r ) of the reference point r that minimizes the evaluation value Er is set as the position of the wireless terminal device B1.

By setting the coordinate at which the evaluation value Er is minimum as the position of the wireless terminal position B, the estimated arrival angle φ _i in the wireless base station apparatuses A1 to AM located closer to the wireless terminal apparatus B1 is prioritized. The position estimation accuracy can be improved. An example will be described with reference to FIG. The actual position P of the wireless terminal device B1 is closer to the reference point 1 than to the reference point 2. Further, the position P is closer to the position of the radio base station apparatus A2 than the position of the radio base station apparatus A1. For this reason, the angle difference | θ ₁₁ −φ ₁ | with respect to the reference point 1 in the radio base station apparatus A1 is almost equal to the angle difference | θ ₁₂ −φ ₁ | with respect to the reference point 2. On the other hand, the angle difference | θ ₂₁ −φ ₂ | with respect to the reference point 1 in the radio base station apparatus A2 is smaller than the angle difference | θ ₂₂ −φ ₂ | with respect to the reference point 2. That is, the angle difference of the radio base station apparatus A2 located near the position P of the radio terminal apparatus B1 more accurately represents the position P of the radio terminal apparatus B1. Therefore, the position P of the wireless terminal device B1 can be estimated with higher accuracy by setting the coordinate at which the square sum Er of the angle difference is the minimum as the position P of the wireless terminal device B1.

Next, the operation of the wireless device configured as described above will be described. When the wireless terminal device B1 transmits a radio signal, the radio unit R1 of the radio base station apparatus A1~AM receives a radio signal transmitted through a plurality of receive antennas # 1~ # N _i. Then, the arrival direction estimation unit T1 of each of the radio base station apparatuses A1 to AM calculates the estimated arrival angle φ _i of the arrival direction of the radio wave from the received radio signal, and the calculated estimated arrival angle φ _i is used as the terminal position estimation apparatus D1. Send to. The terminal position estimation device D1 calculates the evaluation value Er of each reference point by the equation (1) with reference to the estimated arrival angle φ _i received from each of the radio base station devices A1 to AM and θ _ir read from the reference table. The XY coordinate value of the reference point having the smallest evaluation value Er is set as the position of the wireless terminal device B1.

Thus, according to this embodiment, since the reference point with the smallest sum of squares of the angle difference is the position of the wireless terminal device B1, the estimated arrival of the wireless base station device Ai located closer to the wireless terminal device B1 is reached. The angle φ _i is given priority. Thereby, since the position of the wireless terminal device B1 can be estimated with priority on the estimated arrival angle φ _i that is less affected by noise, the position estimation accuracy of the wireless terminal device B1 can be improved.

[Second Embodiment]
Next, a second embodiment of the present invention will be described.
FIG. 6 is a block diagram showing the configuration of the wireless device (terminal position estimation system) according to this embodiment. 6 includes a plurality of radio base station apparatuses S1 to SM and one or a plurality of radio terminal apparatuses B2 (only one is shown in FIG. 6). In the first embodiment, the terminal position estimation device D1 estimates the position of the wireless terminal device B1 based on the estimated arrival angle φ _i estimated by the wireless base station devices A1 to AM. The device B2 includes a plurality of receiving antennas # 1 to #L (L is an integer of 2 or more), and estimates its own position. Here, for convenience of explanation, hereinafter, the i-th radio base station apparatuses S1 to SM are referred to as radio base station apparatuses Si (i = 1, 2,..., M).

FIG. 7 is a schematic diagram for explaining the angle of arrival and the reference point according to the present embodiment. As shown in FIG. 7, an XY coordinate system is defined with a predetermined direction as an X-axis direction and a direction orthogonal to the X-axis direction as a Y-axis direction. Also, R reference points r (r = 1, 2,..., R) are provided in an area where radio communication with the radio base station apparatuses S1 to SM is possible. Further, the XY coordinate value of the reference point r is defined as (x _r , y _r ), and the angle of the arrival direction of the radio wave from the radio base station apparatus Si to the reference point r with respect to the X-axis direction is defined as the arrival angle ψ _ir . . The arrival angle ψ _ir is the direction of the radio wave determined by the positional relationship between the reference point r and the radio base station apparatus Si.

  FIG. 8 is a block diagram illustrating a functional configuration of the wireless terminal device B2 according to the present embodiment. The radio terminal device B2 includes a plurality of receiving antennas # 1 to #L, a radio unit R2 for transmitting and receiving radio signals, an arrival direction estimation unit T2, a terminal position estimation unit D2, a geometric database C2, And a geometric database creation unit C3. The receiving antennas # 1 to #L are arranged in an array to constitute an array antenna. In the present embodiment, the radio unit R2, the arrival direction estimation unit T2, and the terminal position estimation unit D2 are implemented by an electronic circuit or an electric circuit.

The arrival direction estimation unit T2 receives radio waves from the radio base station devices S1 to SM from radio signals from the radio base station devices S1 to SM received by the radio unit R2 via the plurality of reception antennas # 1 to #L. The direction is estimated, and the estimated arrival angle φ ′ _i of the estimated arrival direction is output to the terminal position estimation unit D2. The estimated arrival angle φ ′ _i is an angle of the estimated direction of the radio wave from the radio base station apparatus Si with respect to the X-axis direction. Specifically, the arrival direction estimation unit T2 uses CMA as the arrival direction estimation method. In this embodiment, CMA is used as the arrival direction estimation method, but any method for estimating the arrival direction using a plurality of antennas such as MMSE or MUSIC method may be used.
Further, the radio signals transmitted from the respective radio base station apparatuses S1 to SM have different times transmitted for the respective radio base station apparatuses S1 to SM by time division. Therefore, the wireless terminal device B2 determines which wireless base station device S1 to SM is the wireless signal based on the reception time of the wireless signal. In this embodiment, the radio base station apparatuses S1 to SM are discriminated by time division. However, for example, each radio base station apparatus S1 to S1 is used by using an arbitrary method such as frequency division by transmission frequency or space division by code. The SM radio signal may be determined.

The geometric database C2 (storage unit) stores an XY coordinate value and an arrival angle ψ of a reference point r for each of a plurality of reference points r representing a predetermined position in an area capable of wireless communication with the radio base station apparatuses S1 to SM. _ir (the arrival direction of radio waves from the radio base station apparatuses S1 to SM to the reference point) is stored. The data stored in the geometric database C2 will be described later.
The terminal position estimation unit D2 estimates the position of the wireless terminal device B2 based on the difference between the input estimated arrival angle φ ′ _i and the arrival angle ψ _ir read from the geometric database C2. Detailed processing of the terminal position estimation unit D2 will be described later.
The geometric database creation unit C3 geometrically calculates the arrival angle ψ _ir based on the XY coordinate value of each of the radio base station apparatuses S1 to SM and the XY coordinate value of the reference point r, and the geometric database C2 To store. Note that the XY coordinate value of each of the radio base station apparatuses S1 to SM and the XY coordinate value of the reference point r are set in advance in the radio terminal apparatus B2.

FIG. 9 is a schematic diagram illustrating a data structure and a data example of a reference table stored in the geometric database C2 according to the present embodiment. As shown in the figure, the reference table is two-dimensional tabular data composed of rows and columns, and has columns for each item of a reference point and an arrival angle at the wireless terminal. Each row of this table exists for each reference point. The reference point data (item) holds the XY coordinate values (x _r , y _r ) of the reference point r. The arrival angle at the wireless terminal is an arrival angle ψ _ir of radio waves from each wireless base station device Si to the reference point r.

Next, terminal position estimation processing by the terminal position estimation unit D2 will be described. The terminal position estimation unit D2 first calculates an evaluation value E′r (r = 1, 2,..., R) of each reference point by the following equation (2). Then, the XY coordinate value (x _r , y _r ) of the reference point r that minimizes the evaluation value E′r is set as the position of the wireless terminal device B2.

Next, the operation of the wireless terminal device B2 configured as described above will be described. First, the radio unit R2 receives radio signals from the radio base station apparatuses S1 to SM via the reception antennas # 1 to #L. Then, the arrival direction estimation unit T2 calculates the estimated arrival angle φ ′ _i of the arrival direction of the radio wave from each radio base station apparatus S1 to SM based on the radio signal received from each radio base station apparatus S1 to SM. . Next, the terminal position estimation unit D2 refers to the estimated arrival angle φ ′ _i calculated by the arrival direction estimation unit T2 and the arrival angle ψ _ir read from the reference table, and the evaluation value E of each reference point using Equation (2). 'r is calculated, and the XY coordinate value of the reference point having the smallest evaluation value E'r is set as the position of the wireless terminal device B2.

As described above, according to the present embodiment, since the reference point with the smallest sum of squares of the angle difference is the position of the radio terminal apparatus B2, the estimated arrival of the radio base station apparatus Ai located closer to the radio terminal apparatus B2 The angle φ ′ _i is preferred. Thereby, since the position of the wireless terminal device B2 can be estimated with priority on the estimated arrival angle φ ′ _i that is less influenced by noise, the position estimation accuracy of the wireless terminal device B2 can be improved.

Also, a program for realizing the functions of the terminal position estimation device shown in FIG. 3 or the wireless terminal device shown in FIG. 8 is recorded on a computer-readable recording medium, and the program recorded on the recording medium is stored in the computer system. The terminal position estimation process may be performed by reading and executing. Here, the “computer system” may include an OS and hardware such as peripheral devices.
Further, the “computer system” includes a homepage providing environment (or display environment) if a WWW system is used.
The “computer-readable recording medium” means a flexible disk, a magneto-optical disk, a ROM, a writable nonvolatile memory such as a flash memory, a portable medium such as a CD-ROM, a hard disk built in a computer system, etc. This is a storage device.

Further, the “computer-readable recording medium” means a volatile memory (for example, DRAM (Dynamic DRAM) in a computer system that becomes a server or a client when a program is transmitted through a network such as the Internet or a communication line such as a telephone line. Random Access Memory)), etc., which hold programs for a certain period of time.
The program may be transmitted from a computer system storing the program in a storage device or the like to another computer system via a transmission medium or by a transmission wave in the transmission medium. Here, the “transmission medium” for transmitting the program refers to a medium having a function of transmitting information, such as a network (communication network) such as the Internet or a communication line (communication line) such as a telephone line.
The program may be for realizing a part of the functions described above. Furthermore, what can implement | achieve the function mentioned above in combination with the program already recorded on the computer system, and what is called a difference file (difference program) may be sufficient.

  As described above, the embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to the above, and various design changes and the like can be made without departing from the scope of the present invention. It is possible to

# 1, # 2,..., #N _M , #L Receiving antennas A1, A2,..., AM, S1, S2,..., SM Radio base station equipment B1, B2 Radio terminal equipment C, C2 Geometric database C1, C3 Geometric database creation unit D1 Terminal location estimation device D11 Estimated arrival angle reception unit D2, D12 Terminal location estimation unit R1, R2 Radio unit T1, T2 Arrival direction estimation unit

Claims (14)

Multiple receive antennas;
An arrival direction estimation unit that estimates an arrival direction of radio waves from radio signals transmitted and received between the radio base station apparatus and the radio terminal apparatus received by each of the plurality of reception antennas;
Based on the coordinate values of each of the plurality of radio base station devices and the coordinate values of the plurality of reference points representing the positions, the reference point is determined by the positional relationship between the reference point and the radio base station device for each reference point. A geometric database creation unit for geometrically calculating the direction of radio waves,
For each of the reference points, in association with the direction of the radio wave which is calculated by the geometric database creation unit to the position of the reference point, and the geometric database that stores in advance,
A terminal position estimation unit that estimates the position of the wireless terminal device based on the arrival direction of the radio wave estimated by the arrival direction estimation unit, and the direction and position of the radio wave for each reference point read from the geometric database ;
A terminal position estimation system comprising: Multiple receive antennas;
An arrival direction estimation unit that estimates an arrival direction of a radio wave from a radio signal from a wireless terminal device received by each of the plurality of reception antennas;
A plurality of radio base station devices comprising:
Radio waves from the reference point to each of the radio base station devices for each reference point based on the coordinate values of the plurality of radio base station devices and the coordinate values of a plurality of reference points representing positions. A geometric database creation unit for geometrically calculating the direction of arrival of
For each of the reference points, it associates the incoming direction of the radio wave which is calculated by the geometric database creation unit to the position of the reference point, and the geometric database that stores in advance,
The radio terminal based on a difference between an arrival direction of the radio wave estimated by each of the plurality of radio base station apparatuses and an arrival direction of the radio wave from the reference point read from the geometric database to the radio base station apparatus A terminal position estimator for estimating the position of the device;
A terminal position measuring device installed in the radio base station device or independently from the radio base station device;
A terminal position estimation system comprising: The terminal position estimation unit is configured to calculate an angular difference between an arrival direction of radio waves from the reference point read from the geometric database to the radio base station apparatus and an arrival direction of radio waves estimated by the radio base station apparatus. 3. The terminal according to claim 2, wherein a square is calculated for all the radio base station apparatuses, and the reference point having the smallest sum of squares of the calculated angle differences is set as a position of the radio terminal apparatus. Position estimation system. Estimating the direction of arrival of radio waves from radio signals transmitted and received between a radio base station apparatus and a radio terminal apparatus received by each of a plurality of receiving antennas;
Based on the coordinate values of each of the plurality of radio base station devices and the coordinate values of the plurality of reference points representing the positions, the reference point is determined by the positional relationship between the reference point and the radio base station device for each reference point. Calculating the direction of the radio wave geometrically;
For each of the reference points , associating the direction of the radio wave calculated in the calculating step with the position of the reference point, and storing in advance in a geometric database ;
Estimating a location of the wireless terminal device based an arrival direction of the radio wave estimated in the step of estimating an arrival direction of the radio wave, the radio wave direction and position of each of the reference points read from the geometric database When,
A terminal location estimation method characterized by comprising: The wireless base station device
Estimating a direction of arrival of radio waves from a radio signal from a wireless terminal device received by each of a plurality of receiving antennas;
A terminal position measuring device installed in the radio base station device or independently from the radio base station device ,
Based on each coordinate value of each of a plurality of radio base station devices and each coordinate value of a plurality of reference points representing positions, radio waves from the reference point to each of the radio base station devices for each reference point Calculating the direction of arrival geometrically;
For each of the reference points, and storing the incoming direction of the radio wave calculated in the step of calculating in association with the position of the reference point, the advance geometric database,
An arrival direction of the radio wave which a plurality of the radio base station apparatus estimated respectively, on the basis of the difference between the arrival direction of radio waves from the reference point read from the geometric database to each of the radio base station apparatus radio Estimating the position of the terminal device;
A terminal location estimation method characterized by comprising: The squares of the difference in angle between the arrival direction of the radio wave from the reference point read from the geometric database to the radio base station apparatus and the radio wave arrival direction estimated by the radio base station apparatus are all the radio base stations. 6. The terminal position estimation method according to claim 5, wherein a calculation is performed for a station apparatus, and the position of the wireless terminal apparatus is the reference point having the smallest sum of the squares of the calculated angle differences. Receiving that has a plurality of receiving antennas and receives the direction of arrival of the radio waves estimated from a plurality of radio base station apparatuses that estimate the direction of arrival of radio waves from radio signals from radio terminal apparatuses received by each of the plurality of receiving antennas And
Radio waves from the reference point to each of the radio base station devices for each reference point based on the coordinate values of the plurality of radio base station devices and the coordinate values of a plurality of reference points representing positions. A geometric database creation unit for geometrically calculating the direction of arrival of
For each of the reference points, it associates the incoming direction of the radio wave which is calculated by the geometric database creation unit to the position of the reference point, and the geometric database that stores in advance,
The radio terminal based on a difference between an arrival direction of the radio wave estimated by each of the plurality of radio base station apparatuses and an arrival direction of the radio wave from the reference point read from the geometric database to the radio base station apparatus A terminal position estimator for estimating the position of the device;
And a terminal position measuring apparatus installed in the radio base station apparatus or independently of the radio base station apparatus. The terminal position estimation unit is configured to calculate an angular difference between an arrival direction of radio waves from the reference point read from the geometric database to the radio base station apparatus and an arrival direction of radio waves estimated by the radio base station apparatus. The terminal according to claim 7, wherein a square is calculated for all the radio base station apparatuses, and the reference point having the smallest sum of the squares of the calculated angle differences is set as the position of the radio terminal apparatus. Position measuring device. A terminal position estimation system comprising a wireless terminal device having a plurality of receiving antennas and a plurality of wireless base station devices that transmit wireless signals to the wireless terminal device,
The wireless terminal device
A direction-of-arrival estimation unit that estimates a direction of arrival of radio waves from each of the radio base station devices from radio signals from the plurality of radio base station devices received by each of the plurality of reception antennas;
Based on each coordinate value of each of the plurality of radio base station devices and each coordinate value of a plurality of reference points representing positions, for each reference point, from each of the plurality of radio base station devices to the reference point A geometric database creation unit for geometrically calculating the direction of arrival of radio waves,
For each of the reference points, it associates the incoming direction of the radio wave which is calculated by the geometric database creation unit to the position of the reference point, and the geometric database that stores in advance,
The difference between the arrival direction of the radio wave from each of the radio base station devices estimated by the arrival direction estimation unit and the arrival direction of the radio wave from each of the radio base station devices read from the geometric database to the reference point A terminal position estimator for estimating the position of the own apparatus based on;
A terminal position estimation system comprising: The terminal position estimation unit is configured to read the arrival direction of radio waves from the radio base station apparatus read from the geometric database to the reference point, and arrival of radio waves from the radio base station apparatus estimated by the arrival direction estimation unit. The square of the angle difference with respect to the direction is calculated for all the radio base station apparatuses, and the reference point having the smallest sum of the squares of the calculated angle difference is set as the position of the own apparatus. 10. The terminal position estimation system according to 9. No line terminal device,
Estimating an arrival direction of radio waves from each of the radio base station devices from radio signals from a plurality of radio base station devices received by each of the plurality of receiving antennas;
Based on each coordinate value of each of the plurality of radio base station devices and each coordinate value of a plurality of reference points representing positions, for each reference point, from each of the plurality of radio base station devices to the reference point Calculating the direction of arrival of radio waves geometrically;
For each reference point, associating the direction of arrival of the radio wave calculated in the calculating step with the position of the reference point, and storing in advance in a geometric database;
The direction of arrival of radio waves from each of the radio base station devices estimated in the step of estimating the direction of arrival of radio waves and the direction of arrival of radio waves from each of the radio base station devices read from the geometric database to the reference point Estimating the position of the device based on the difference between,
A terminal location estimation method characterized by comprising: The squares of the difference in angle between the arrival direction of radio waves from the radio base station apparatus read from the geometric database to the reference point and the estimated arrival direction of radio waves from the radio base station apparatus are all the radio The terminal position estimation method according to claim 11, wherein the terminal point is calculated for a base station device, and the reference point having the smallest sum of squares of the calculated angle differences is set as a position of the own device. Multiple receive antennas;
A direction-of-arrival estimation unit that estimates a direction of arrival of radio waves from each of the radio base station devices from radio signals from a plurality of radio base station devices received by each of the plurality of reception antennas;
Based on each coordinate value of each of the plurality of radio base station devices and each coordinate value of a plurality of reference points representing positions, for each reference point, from each of the plurality of radio base station devices to the reference point A geometric database creation unit for geometrically calculating the direction of arrival of radio waves,
For each of the reference points, it associates the incoming direction of the radio wave which is calculated by the geometric database creation unit to the position of the reference point, and the geometric database that stores in advance,
The difference between the arrival direction of the radio wave from each of the radio base station devices estimated by the arrival direction estimation unit and the arrival direction of the radio wave from each of the radio base station devices read from the geometric database to the reference point A terminal position estimator for estimating the position of the own apparatus based on;
A wireless terminal device comprising: The terminal position estimation unit is configured to read the arrival direction of radio waves from the radio base station apparatus read from the geometric database to the reference point, and arrival of radio waves from the radio base station apparatus estimated by the arrival direction estimation unit. The square of the angle difference with respect to the direction is calculated for all the radio base station apparatuses, and the reference point having the smallest sum of the squares of the calculated angle difference is set as the position of the own apparatus. 13. The wireless terminal device according to 13.

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