JP2013142637A - Direction measuring device, information processing device, and direction measuring method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately obtain a direction in which a device faces and a position in a vertical direction at high speed, without obtaining an integer value bias.SOLUTION: In a direction measuring device 20, a phase determining portion 5 obtains phases of waves of at least two radio signals received by receivers 21-2n. A phase difference calculating portion 6 measures phase difference between the waves of the at least two radio signals, and an angle calculating portion 7 calculates a direction on the basis of the measured phase difference. The receivers 21-2n are disposed so as to make an absolute value of the phase difference between the waves of the respectively received radio signals less than 0.5. Therefore, the phase difference can be made to be less than 0.5, and the phase difference can be decided without considering the integer value bias. A direction based on the phase difference can be decided.

Description

  The present invention relates to a direction measuring device, an information processing device, and a direction measuring method for measuring a direction in which the device is facing.

  As means for measuring the direction, an azimuth magnetic needle and an electronic compass using magnetism are known. But they point to magnetic north, not true north. Furthermore, the measurement result comes from an electronic device that is weak against changes in the surrounding magnetism and generates magnetism around it, and calibration is required.

  There is a gyro compass that points to true north and is not affected by the surrounding magnetism, but it is very large and takes about 2-3 hours from startup because it can acquire the direction normally. In addition, there is a GPS compass as disclosed in Patent Documents 1 and 2 that is not affected by the surrounding magnetism and points to true north and starts quickly.

JP 2002-267737 A JP 2001-264406 A

The direction measurement method in the GPS compass is basically the direction of the vector ab generated by the receivers a and b by measuring the path difference d of the GPS wave received by the receiver a and the receiver b as shown in FIG. Ask for.
The path difference is the path difference d = phase difference Φ × carrier wavelength λ
It can be expressed as

  In the two receivers a and b, the path difference d can be obtained from the carrier phase of the wave received by each receiver.

ここで、ｆは周波数、ｃは光速、ρ^ｊ _ｉ（ｔ）は、t秒間に進んだ波の数、Ｎ^ｊ _ｉは整数値バイアス、ｆσ^ｊ（ｔ）は衛星誤差、ｆσ_ｉ（ｔ）は、受信機誤差である。 The carrier phase at time t in the GPS receiver i and satellite j can be expressed by the following equation.

Here, f is the frequency, c is the speed of light, ρ ^j _i (t) is the number of waves that have traveled in t seconds, N ^j _i is the integer value bias, fσ ^j (t) is the satellite error, and fσ _i (t) Is the receiver error.

  The carrier phase indicates the number of waves in the carrier wave between the satellite and the receiver including an integer bias, satellite error, and receiver error. Satellite error and receiver error can be eliminated by obtaining the double phase difference, but the integer bias cannot be eliminated.

  The satellite receiver can measure the fraction when the radio wave arrives (and the subsequent integrated value), and only the fraction of one wave or less. I don't know how many of the carrier waves that leave the satellite. Of the radio wave arriving from the satellite to the receiver, only a fractional part can be measured, but it is difficult to measure how many integer parts there are. This difficult part is the integer bias. How to find this integer value bias is a problem when inventing the GPS compass. There is a calculation method for obtaining this integer value bias, but it is very complicated, and it takes time to obtain it by calculation, and a waiting time is required until it is used.

  In Patent Document 1, a time difference is used to eliminate the waiting time, and the integer value bias is eliminated by taking the difference between the previous data and the current data. However, it is necessary to use angular velocity data output from the gyro sensor when obtaining the direction. The angular velocity obtained from the gyro sensor is obtained by integrating data measured by the sensor. For this reason, there is a problem that measurement errors mainly due to sensor drift are integrated with the lapse of time by integration, and the errors become larger and larger.

  In Patent Document 2, the measured path difference is compared with the path difference obtained by calculation by changing the baseline vector between the antennas using the measured GPS carrier wave, and the baseline with the smallest error between the measured value and the calculated value. Find the direction from the vector. However, in this method, although there is an integer value bias of the phase data, since only a decimal value that can be measured is seen, an accurate path difference cannot be obtained. Therefore, the difference between the measured value and the calculated value is changed by changing the baseline vector by 1 degree from 1 degree to 360 degrees, and the difference between the measured value and the calculated value is examined for each angle. Determine the direction of the device. However, since it is necessary to calculate from 1 to 360 degrees one by one, in the corresponding patent, the direction is obtained in two dimensions on the xy plane, but if one dimension is increased to three dimensions (such as obtaining the vertical direction), a huge amount of calculation is required. It becomes quantity. Further, since the path difference is not uniquely determined from the phase difference, phase difference (path difference) data obtained from satellite signals in various directions is used, and the number of satellites necessary for obtaining the direction increases.

  Therefore, in the present invention, the present invention solves the above-described problem, and a direction measuring device and an information processing device that can determine the direction in which the device is directed at high speed and high accuracy without obtaining an integer bias. And it aims at providing a direction measuring method.

  In order to solve the above-described problem, the direction measuring apparatus of the present invention measures the current position based on at least two or more receiving means for receiving a wave of a radio signal and the radio signal received by the receiving means. Positioning means, a calculating means for calculating an azimuth angle and an elevation angle based on the current position of the device measured by the positioning means, and a phase for acquiring the phase of the wave of the radio signal received by the receiving means, respectively An acquisition means; a phase difference measurement means for measuring a phase difference between two radio signal waves acquired by the phase acquisition means; and a direction from a current position measured by the positioning means, the phase difference measurement means Direction calculation means for calculating based on the phase difference measured by the two or more receiving means, the wave received by one receiving means and the wave received by another receiving means The absolute value of the phase difference is arranged to be less than 0.5.

  The direction measuring method of the present invention is arranged so that the absolute value of the phase difference between the wave received by one receiving means and the wave received by another receiving means is less than 0.5. In a direction measuring method in a direction measuring device comprising a plurality of receiving means, two or more receiving steps for receiving a wave of a radio signal, and a positioning step for positioning a current position based on the radio signal received by the receiving step A calculation step for calculating an azimuth angle and an elevation angle based on the current position of the device measured by the positioning step, and a phase acquisition step for acquiring the phase of the wave of the radio signal received by the reception step, respectively. A phase difference measurement step for measuring a phase difference between two radio signals acquired by the phase acquisition step, and a phase difference measurement step. The absolute value of the phase difference and a, a direction calculation step of calculating a direction towards based on the phase difference of less than 0.5.

  According to the present invention, the current position is measured based on the radio signal, and the azimuth angle and the elevation angle are calculated based on the measured current position of the device. Then, the phase of the wave of at least two received radio signals is respectively acquired, the phase difference between the waves of the at least two radio signals is measured, and the direction from the current position of the apparatus is determined based on the measured phase difference Is calculated. And the receiving means is arranged so that the absolute value of the phase difference with each received radio signal wave is less than 0.5. As a result, the absolute value of the phase difference can be less than 0.5, the phase difference can be determined without considering the integer value bias, and the direction based on the phase difference can be determined.

  In the direction measuring device according to the present invention, at least three receiving units are arranged, and are determined by the state determining unit that determines at least one of the inclination and the movement of the direction measuring device, and the state determining unit. Determining means for determining a combination of two receiving means out of the at least three receiving means based on at least one of a tilt and a movement, wherein the direction calculating means is the reception determined by the determining means. The direction of the direction measuring device is calculated based on the wave of the radio signal received by the means.

  According to the present invention, at least three receiving means are arranged, determine at least one state of inclination and movement of the direction measuring device, and based on at least one of the determined inclination and movement. Among the receiving means, a combination of two receiving means is determined. Then, the direction of the direction measuring device is calculated based on the wave of the radio signal received by the receiving means for which the combination is determined. Thereby, an appropriate antenna combination based on the state of the apparatus can be determined, and an accurate direction can be calculated.

  Further, in the direction measuring apparatus of the present invention, the at least two or more receiving units receive a radio signal from a GPS satellite, and the at least two or more receiving units receive a radio signal from the GPS satellite. It is characterized by being arranged at intervals of 1/2 or less of the wavelength of the signal.

  According to the present invention, the receiving means can receive a radio signal from a GPS satellite, and is arranged at an interval equal to or less than one half of the wavelength of the radio signal. The absolute value can be less than 0.5. Therefore, an accurate direction can be calculated.

  The information processing apparatus according to the present invention includes the above-described direction measurement device, content storage means for storing content data and an arrangement position in the real space, and a location based on the calculated direction / position in the direction measurement device. Display means for displaying the content stored in the content storage means.

  According to the present invention, the stored content is displayed at a location based on the direction / position calculated by the direction measuring device. Accordingly, the content can be displayed at a location based on the accurate direction and position, and accurate information, that is, a real space in which the content is synthesized can be provided to the user.

  An information processing apparatus according to the present invention includes the direction measuring device and display means for displaying a direction from a current position measured by the direction measuring device. Thereby, the user can know the direction from the current position and can use it as a compass.

  According to the present invention, it is possible to determine the phase difference between the received waves of at least two radio signals without considering the integer value bias, and to determine the direction based on the phase difference.

It is a conceptual diagram of the path difference in two receivers. 3 is a block diagram illustrating functional configurations of a transmission unit 1 and a direction measuring device 20. FIG. It is explanatory drawing which compares the phase of the wave which two receivers received. It is the figure which showed typically a mode that the wave of the GPS signal transmitted from a GPS satellite was received in the receiver 21 and the receiver 22. FIG. It is explanatory drawing which compared the phase difference in two receivers. It is explanatory drawing which compared the phase difference in two receivers, and determined the phase in which the absolute value of a phase difference is less than 0.5. It is the schematic diagram which showed typically the position of the receiver 22 centering on the receiver 21. FIG. It is explanatory drawing which shows the direction using the azimuth and elevation angle with respect to the transmission part 1 from the receiver 21. FIG. It is a general-view figure when the direction measuring device 20 is applied to a glasses-type display. 4 is a flowchart showing processing of the direction measuring device 20. 1 is an overview diagram of a mobile terminal 100 on which a direction measuring device 20 is mounted. 4 is a flowchart showing processing for detecting the position and direction of the mobile terminal 100. 4 is a schematic diagram illustrating an angle of an operation surface when operating the mobile terminal 100. FIG. FIG. 6 is a schematic diagram showing a direction when operating the mobile terminal 100. It is a flowchart which shows the process of the portable terminal 100 in a modification. It is explanatory drawing which shows the modification which made the arrangement position of the camera into the side part in the portable terminal.

  Embodiments of the present invention will be described with reference to the accompanying drawings. Where possible, the same parts are denoted by the same reference numerals, and redundant description is omitted.

  In the present invention, the direction of the inter-receiver vector (base line vector) is obtained from the path difference (phase difference). In the present invention, the inter-receiver vector (base line vector) indicates the direction of the apparatus. In FIG. 2, the block diagram which shows the function structure of the transmission part 1 in this embodiment and the direction measuring device 20 is shown. The transmission unit 1 includes transmitters 1 to 1n. The direction measuring device 20 includes a reception unit 2 (reception unit), a receiver position calculation unit 3 (positioning unit), and a positional relationship calculation unit 4 ( Calculation unit), phase determination unit 5 (phase acquisition unit), phase difference calculation unit 6 (phase difference measurement unit), angle calculation unit 7 (direction calculation unit), virtual camera operation unit 8, content storage unit 9 (content storage unit) ), A content display unit 10 (compositing unit, display unit), and a state determination unit 31 (state determination unit).

  The transmission unit 1 is, for example, a GPS satellite or a radio base station, and generates a wave that travels in the air. If the transmitter 1 generates a wave that travels wirelessly, such as a GPS signal or a mobile phone radio wave, Anything. In the present embodiment, the transmission unit 1 will be described as a set of GPS satellites.

  The transmission unit 1 is a part that represents a set of GPS satellites that transmit GPS signals, and includes transmitters 11 to 1n that are GPS satellites. Each of the transmitters 11 to 1n transmits a GPS signal to which position information of the transmitter is added. Therefore, the positions of the transmitters 11 to 1n are always grasped by the direction measuring device 20. In addition, as long as the position of each transmitter 11-1n can be acquired, it may be anything and is not limited to the GPS satellite, and each transmitter 11-1n may be fixed.

  Each of the transmitters 11 to 1n may be one, or a plurality of transmitters may be used when increasing the accuracy or measuring the position of the receiver. In particular, when measuring the position (x, y, z) of the receiving unit 2, the required receiver position dimension plus one transmitter is required.

  Next, the direction measuring device 20 will be described. The receiving unit 2 is for receiving a wave transmitted from the transmitting unit 1 (any one of the transmitters 11 to 1n). At least two units are required, and the two receivers 21 and 22 are arranged so that the absolute value of the phase difference of the received waves (for example, GPS signals) is less than 0.5. Taking FIG. 1 as an example, since the path difference d does not become longer than the length between the receiver 21 and the receiver 22, for simplicity, the distance between the receivers of the receiver 21 and the receiver 22. May be set to a length equal to or less than ½ of the wavelength of the wave generated from the transmitter 1 (any one of the transmitters 11 to 1n). However, the distance between the receivers may be longer than ½ of the wavelength as long as the path difference d does not become more than ½ of the wavelength. Since the path difference is determined by the positional relationship between the receiver and the transmitter, for example, it is understood that the transmitter is fixed and the receiver is moved within a range in which the path difference does not exceed 1/2 of the wavelength by calculation. (When the movable range of the receiver is determined in advance).

  In order to improve the measurement accuracy or increase the dimension of measurement results, three or more receivers 21 to 2n can be used as well as the transmitter. In this case, the waves received by any of the receivers 21 to 2n are arranged so that the absolute value of the phase difference from the waves received by at least one other receiver is less than 0.5. For example, in the case of a GPS signal, since the wavelength is about 19 cm, the receivers 21 to 2n are arranged with an interval equal to or less than half the length thereof. Since this direction measuring device 20 is assumed to be mounted on a portable terminal, the receiver itself is movable, but the positional relationship between the receivers is fixed (the relative positional relationship of the receiving engines). Can be carried if they are the same).

  The receiver position calculation unit 3 is a part for obtaining the position (for example, latitude, longitude, sea level, etc.) of at least one receiver (particularly the antenna portion). At this time, the position of the antenna to be obtained may be two-dimensional or three-dimensional, and the desired dimension + 1 transmitter is used. The method for obtaining the position of one antenna may be single positioning used in GPS positioning or DGPS positioning using a reference station whose position is known in advance, and a known method can be used.

  The positional relationship calculation unit 4 calculates the position of the transmitter 11 viewed from the receiver 21 based on the position information of the receiver obtained from the receiver position calculation unit 3 and the position information of the transmitter. It is desirable to represent the azimuth angle α and the elevation angle β of the transmitter 11 as viewed from the receiver 21, and a known method such as a method used in GPS positioning can be used as a method to be obtained. In addition, although the receiver 21 and the transmitter 11 were taken as an example as an example, it is not limited to this, and any of the receivers 21 to 2n may be used as a reference. The same applies to the transmitter.

  The phase determination unit 5 obtains the phase of each wave received by the reception unit 2. If the frequency of the wave transmitted from the transmitter 1 is low and the phase of the transmitted wave can be received with sufficient accuracy, only the fractional value of the phase of the received wave needs to be viewed. If the frequency of the wave transmitted from the transmitter 1 is very high, the wave phase is measured by down-converting the interference wave by multiplying it with the received wave.

  The phase difference calculation unit 6 is a part that calculates the phase difference of each receiver obtained by the phase determination unit 5. What is required is the difference between the two receivers. If there are three or more receivers 21, 22, 23..., Two pairs are selected from the receivers 21 and 22. The receiver 22 and the receiver 23, the receiver 23 and the receiver 24, and the phase difference between the two receivers are calculated. And the phase difference calculation part 6 calculates the path difference d based on this phase difference. That is, the phase difference calculation unit 6 calculates the path difference d by calculating the path difference d = wavelength × phase difference.

  Here, a method of calculating the phase difference will be described more specifically. Of the numerical values that can be received by the receiving unit 2, only the fractional value of the phase at the time of arrival can be detected accurately, but the number of waves (integer) cannot be detected accurately. For example, as illustrated in FIG. 3, if the wave measured by the receiver 21 at the time of wave reception is the 2.3th wave transmitted from the transmitter 11, the value of the fractional portion of the obtained phase is 0. 3 (cycle). At the same time, if the value of the fractional part of the phase that can be measured by the receiver 22 is 0.7 (cycle), the phase difference (the value of the fractional part of the phase of the receiver 21-the value of the fractional part of the phase of the receiver 22) is -0. 4 (cycle).

  If the wave received by the receiver 22 is the 2.7th wave, the phase difference may be -0.4 (cycle), but if it is the 1.7th wave, the correct phase difference is 0. 6 (cycle). However, the phase difference measured even at the 1.7th wave is −0.4 (cycle), and the correct path difference d cannot be obtained only from the phase difference. This is a measurement problem due to the fact that the integer part of the number of waves cannot be calculated accurately (integer value bias) (the phase alone alone does not make it possible to distinguish between Lee Lo Ha in FIG. 3).

  However, for example, if it is known that the phase difference does not exceed 0.5, the wave received by the receiver 22 is not a wave other than the 2.7th wave, and the path difference d is It can be determined accurately.

  A specific example of the phase difference will be described. FIG. 4 is a diagram schematically showing how the receiver 21 and the receiver 22 receive a wave of a GPS signal transmitted from a GPS satellite.

  As shown in FIG. 4, the path difference d can be calculated by obtaining the phase difference between the waves at the receiver 21 and the receiver 22. This path difference d is the difference between the phase of the wave received by the receiver 21 and the phase of the wave received by the receiver 22, but as shown in FIG. is important. As shown in FIG. 5, the phase of the wave received by the receiver 21 is xxx. 3 and the phase of the wave received by the receiver 22 is xxx. In the case of 7, the phase difference is obtained based on each phase. However, for example, when the phase value of the wave received by the receiver 21 is 1.3, the phase value of the wave received by the receiver 22 is either 0.7, 1.7, or 2.7, The phase difference is different. That is, the phase difference is 0.6, −0.4, or −1.4. In addition, although the above-mentioned xxx is an integer value, it has shown the part where it is difficult to measure correctly.

  However, if it is given as a precondition that the absolute value of the phase difference is less than 0.5, the phase difference can be easily determined. That is, it can be seen that the phase at which the absolute value of the phase difference in the receiver 21 is less than 0.5 is (b) in FIG.

  Thus, if it is known that the absolute value of the phase difference is less than 0.5, it is accurate only with the fractional part of the phase that can be obtained by the receiver 21 without considering the integer part of the wave. The path difference d can be obtained. In other words, it is not necessary to consider the integer bias that is a problem in satellite positioning.

  In this embodiment, when the receiver 21 is used as a reference, in order to grasp which side the phase received by the receiver 22 is shifted with respect to the phase received by the receiver 21, A phase whose absolute value is less than 0.5 is to be used.

  The angle calculation unit 7 obtains the azimuth angle α and elevation angle β from the receiver 21 to the transmission unit 1 (any one of the transmitters 11 to 1n) calculated by the positional relationship calculation unit 4 and the phase difference calculation unit 6. Based on the phase difference, the base line vector between the receiver 21 and the receiver 22 is calculated, and the direction in which the device is facing is calculated. This direction can be expressed by an angle from the initial value, and true north is set in advance. Details will be described below.

For example, when there are two receivers as the receiver 21 and the receiver 22, when the direction on the xy plane is obtained, the receiver 21 is arranged at the origin of the coordinate system,
(Xa, ya, za) = (0, 0, 0) (2)
It becomes. As shown in FIG. 7, when the distance between the other receiver 22 (coordinate b) and the receiver 21 (coordinate a: origin) is L and the angle from the y-axis is θ, the receiver 22 is (Xb, yb, zb) = (Lsin θ, L cos θ, 0) (3)
It can be expressed as.

Further, as shown in FIG. 8, using the azimuth angle α and elevation angle β from the receiver 21 to the transmitter 1 (any one of the transmitters 11 to 1 n) calculated by the positional relationship calculator 4, the transmitter When 1 is sufficiently far from the receiver, the direction cosine vector S at that time is
S = (cosβ · sinα, cosβ · cosα, sinβ) (4)
It becomes.

The path difference d is the inner product of the baseline vector (the vector of the receiver 21 and the receiver 22) and the direction cosine vector S,
d = cos β (xb · sin α + yb · cos α) (5)
It can be expressed as

When actually performing the measurement, a double phase difference is obtained in order to eliminate the transmitter error and the antenna error. Transmitters 11 and 12 use the double phase difference when the wavelength of the transmission wave is λ (d ₁₁ −d ₁₂ ) / λ = {cos β 11 (xb · sin α 11 + yb · cos α 11) −cos β12 (xb · sin α 12 + yb · cos α 12 )} / Λ (6)
It becomes. Since α and β are obtained from the satellite signal by the positional relationship calculation unit 4, the values of xb and yb of the baseline vector can be obtained from the measured (d ₁₁ −d ₁₂ ). Since there are two unknowns, two equations are required. Therefore using the transmitter (e.g. transmitter N13) other _one, d 11 _{-d 13} obtains. If there are a total of three transmitters, the direction on the two-dimensional plane can be obtained.

Since θ in Equation (3) is the same value, θ may be obtained using a relationship of sin ² θ + cos ² θ = 1.

  Rather than calculating the direction by calculation, the value of the double phase difference obtained when the baseline vector is changed by 1 to 360 degrees is calculated in advance, and the value actually obtained by measurement is referred to You may ask for it. In this case, a double phase difference that does not include an integer value bias is obtained. Therefore, even if the calculated values of 1 to 360 degrees are not referred to, they coincide with the obtained measured values, or some value of measured values ± error. You just need to look up.

  If the absolute position of at least one of the receivers 21 and 22 (for example, latitude, longitude, sea level, etc.) is known in advance, or if the receiver position calculation unit 3 can accurately obtain the position of the receiver, these positions Can be used to determine the base line vector formed by the two receivers from the position information of one receiver and the position information of the transmitter and the phase difference obtained by the phase difference calculator 6.

  If the dimension of the desired direction is increased by one to make it three-dimensional, the unknowns are xb, yb, and zb, which can be solved by increasing another transmitter. In this way, even if the dimension increases by one, it is only necessary to obtain three expressions.

  The virtual camera operation unit 8 acquires the position calculated by the receiver position calculation unit 3 and the angle (that is, the direction) calculated by the angle calculation unit 7, and virtual images the content space based on the position and angle. This is a part for acquiring content visible from the camera viewpoint from the content storage unit 9.

  The content storage unit 9 is a part for storing content to be superimposed and displayed, and this content is stored in association with the position / direction of the real space. When the direction measuring device 20 faces a specific position / direction, the content is stored so that content associated with the position / direction is acquired. For example, if the content is information on a sign that is superimposed on a building, it is known which direction the content is facing and which side is placed in front, and based on that direction Content is stored in such a way that it can be arranged.

  The content display unit 10 is a part that displays a video from the viewpoint of the virtual camera obtained by the virtual camera operation unit 8 in the content of the content storage unit 9. For example, as shown in FIG. 9, the content display unit 10 is an optical see-through HMD (Head Mounted Display), and the user sees the scenery in the real space through the lens, and the content is displayed inside the lens. Is displayed. As a result, the user can view the content so that the content is superimposed on the landscape. Note that, using a device having a display and a camera that captures surrounding images, such as a mobile terminal, the real space image may be captured by the camera, and the content may be superimposed on the acquired real space image.

  The state determination unit 31 is a part that determines the state of the direction measuring device 20. For example, the state determination unit 31 determines the state of the direction measurement device 20, that is, how much the device is inclined in which direction, using a gyroscope, an acceleration sensor, or the like. Note that the user may input the state of the direction measuring device 20. For example, in the portable terminal 100 described later, when an application that uses a camera is activated or a camera is specified to be used, The state is determined naturally. That is, it is preset that the camera can be used, and the set numerical value may be used. In the mobile terminal 100 to be described later, the state is generally set in the vertical direction. Similarly, it is also possible to determine the movement by a gyro and the like, and to determine the inclination which is the state of the apparatus based on the movement.

  FIG. 9 shows an overview when the direction measuring device 20 configured as described above is applied to a glasses-type display that is an HMD. As shown in FIG. 9, the receiver 21 and the receiver 22 are arranged at the tip portion of the vine of the glasses and the coupling portion of the lens of the glasses and the vine, respectively. This glasses-type display forms a display (that corresponds to the content display unit 10) for displaying content inside the lens with respect to an actual scenery or the like viewed through the lens when the user wears glasses. Thus, the landscape and the content can be superimposed. Here, it is preferable that the length between the receiver 21 and the receiver 22 is ½ or less of the wavelength. Since the GPS carrier wave is about 19 cm, the interval is about 9.5 cm or less, and will be described below. When the distance between the receivers is 9.5 cm, the absolute value of the phase difference when the GPS satellite is used can be made less than 0.5.

  Next, processing of the direction measuring device 20 configured as described above will be described. FIG. 10 is a flowchart showing processing of the direction measuring device 20. Here, four GPSq · r · s · t are used as transmitters, and two receivers capable of receiving GPS carrier waves (L1 wave: wavelength of about 19 cm) are used. Let them be receivers 21 and 22, respectively.

  First, an optical see-through HMD is used for the content display unit 10, and the receiver 21 and the receiver 22 are arranged in advance at an interval of 9.5 cm or less on the glasses-type HMD. Normally, the receiver 21 and the receiver 22 are fixedly arranged on the same terminal in advance. Then, the receivers 21 and 22 receive the GPS carrier wave L1 (S701). Then, the receiver position calculation unit 3 determines the absolute position (latitude, longitude, sea level, etc.) of the receiver 21 from the four satellites (S702).

  The positional relationship calculation unit 4 obtains the elevation angle β and the azimuth angle α of the GPS q · r · s · t as seen from the receiver 21 (S703). Then, the phase judgment unit 5 multiplies the received waveform by the radio wave in the frequency converter, extracts only the difference (down-conversion), and derives the carrier phase formula (S704). In this case, satellite error and antenna error remain included.

  Next, the phase difference calculation unit 6 obtains the phase difference between the receiver 21 and the receiver 22 of each wave of GPSq · r · s · t (S705). In the case of this form, the carrier phase equation derived in step S703 includes a satellite error and an antenna error, so a double phase difference is obtained.

  The phase difference calculation unit 6 obtains a baseline vector between the receiver 21 and the receiver 22 based on the receiver 21 from the difference in the path difference d based on the obtained double phase differences ( S706). To obtain the direction, the initial value (reference) of the baseline vector must be known. Thus, the initial values are set to true north / horizontal with the receiver 21 as coordinates (0,0,0) and the receiver 22 as coordinates (0,9.5,0). This “9.5” is determined based on 9.5 cm, and for convenience, 1 cm is taken as one unit of the coordinate axis.

  The direction from the initial value and the absolute position of the device, which the direction measuring device 20 is obtained in steps S702 and S706, are output to the content storage unit 9 where content is stored for content operation.

  Content arrangement information in the real space is constructed in the content storage unit 9, and text and image content are arranged according to the coordinates (Xv, Yv, Zv) in the real space. The virtual camera operation unit 8 acquires content from the content storage unit 9 based on the information on the direction of the device and the absolute position of the device obtained in steps S702 and S706, and the content is formed inside the lens. When the content display unit 10 is displayed, the real space and the content can be superimposed and displayed. (S708).

  As a result, when augmented reality (AR) is realized, the ambient lighting environment (including sunshine) and the angle at which the object is viewed differ depending on the viewing position from the user. There is a problem that is difficult. However, by using this method, it is not necessary to recognize an object in the real space, and a stable AR world can be realized.

  In this method, a double phase difference is used when obtaining a phase difference. However, a single phase difference may be used if a certain amount of error is allowed. Other than that, use a device in which the receiver and the transmitter are synchronized in advance, or if the receiver can receive with sufficient accuracy without down-converting the wave generated from the transmitter 1 It may be a multiple phase difference.

  Further, in the case of the method of obtaining the direction in two dimensions from the double phase difference, when there are only two transmitters, the base line vector can be similarly obtained by adding one more receiver. In this case, the receiver is arranged so that at least the absolute value of the phase difference from the receiver 21 or the receiver 22 is less than 0.5. The positional relationship between these receivers is fixed and does not change. The number of antennas may be a dimension in the direction in which the number of vectors + 1 so that the absolute value of the phase difference is less than 0.5 + 1 is desired.

  Next, an application example of content display based on the terminal position and direction using the baseline vector thus derived will be described.

  FIG. 11 is an overview of the mobile terminal 100 equipped with the direction measuring device 20 of the present embodiment. As illustrated in FIG. 11, the mobile terminal 100 is an information processing apparatus that includes antennas 101 to 104, a camera 108, a display 110, and a CPU 111. In this embodiment, the portable terminal 100 has a rectangular parallelepiped shape.

  The antennas 101 to 104 are portions that receive signals from GPS satellites, and correspond to the receivers 21 to 24 in the above-described embodiment. Centering on the antenna 101, the antennas 102 to 104 are arranged in different directions. As shown in FIG. 11A, the antenna 102 is installed at a corner in the depth direction when the display 110 is viewed from the front, and is arranged on an axis parallel to the shooting direction of the camera 108. The antenna 103 is disposed at a corner in the longitudinal direction of the display, and the antenna 104 is disposed at a corner in a direction perpendicular to the longitudinal direction on the same plane as the display 110. As described above, in order to make the absolute value of the phase difference less than 0.5, each antenna needs to be 9.5 cm or less.

  In addition, in this embodiment, since the portable terminal 100 assumed the shape of a rectangular parallelepiped, it became the above-mentioned description, However, The antenna should just be arrange | positioned with respect to a different direction from a certain part of a portable terminal. .

  The camera 108 is a part that acquires shooting data, and is disposed on the back side of the display 110. This corresponds to the virtual camera operation unit 8 in the direction measuring device 20.

  The display 110 is a part that displays shooting data acquired by the camera 108 and also displays content stored in the mobile terminal 100 or content acquired via an external network. This corresponds to the direction measurement device 20 content display unit 10.

  The CPU 111 is a control part built in the mobile terminal 100, and executes processing for functioning as a mobile phone, and also includes the above-described phase determination unit 5, receiver position calculation unit 3, positional relationship calculation unit 4, Each function of the phase difference calculation unit 6 and the angle calculation unit 7 is executed.

  In addition, the mobile terminal 100 includes a memory unit corresponding to the content storage unit 9. Alternatively, the content storage unit 9 and the virtual camera operation unit 8 may be provided in a content server on the NW. When the content storage unit 9 and the virtual camera operation unit 8 exist on the content server via the NW, the mobile terminal 100 transmits the obtained position and direction of the mobile terminal 100 to the virtual camera operation unit 8 on the content server. Then, the virtual camera is operated based on the position and direction, the content video at the virtual camera viewpoint is acquired from the content storage unit 9, the content video is transmitted to the mobile terminal 100 and displayed on the mobile terminal 100. .

  Processing of the mobile terminal 100 configured as described above will be described. FIG. 12 is a flowchart illustrating a process for detecting the position and direction of the mobile terminal 100 based on a signal received by any combination of the antennas 101 to 104.

  First, whether or not the camera 108 is used is set by a user operation (S802). This is performed based on an operation unit (not shown). If the camera use is selected here, it is determined that the camera 108 provided on the back surface of the mobile terminal 100 is used. Whether or not the camera can be used can be determined based on the orientation of the camera. For example, as shown in FIG. 13A, the mobile terminal 100 can be photographed with the camera standing substantially perpendicular to the horizontal plane. If it is possible, that is, if it is substantially parallel to the XZ plane, it is determined that use of the camera has been selected. Also, as shown in FIG. 13B, when it is determined that the camera is substantially parallel to the XY plane, it is determined that the camera use is not selected. As a case where a camera is used, there is a case where an AR application is desired to be activated. The orientation of the camera can be grasped by measuring the direction and inclination of the device with an acceleration sensor mounted on the device.

  If it is determined that the camera is used, a wave of a signal from the GPS is received using the antenna 101 and the antenna 102 (S802). Then, the position and direction of the portable terminal are determined by the CPU 111 based on the wave of the GPS signal (S803). The position and direction determined by the communication unit (not shown) are transmitted to the content server, and the content based on the position and direction is received (S804). Then, the content transmitted from the content server is superimposed on the image data captured by the camera 108 and displayed on the display 110 (S805).

  Further, when the mobile terminal 100 is in a state substantially parallel to the XY plane as shown in FIG. 13B by a user operation, it is determined that the camera is not used, and the antenna 101 and the antenna A wave from GPS is received using 103 (S806). Note that a combination of the antenna 101 and the antenna 104 may be used according to the inclination of the mobile terminal 100. For example, as shown in FIG. 14A, when the user points the mobile terminal 100 in the vertical direction (when the display is used so that it looks vertically long), the antenna 101 and the antenna 103 are selected. As shown in FIG. 14B, when the portable terminal 100 is turned sideways, the antennas 101 and 104 are selected. Further, in determining whether or not they are parallel, it is only necessary to determine that they have a certain width and are approximately parallel.

  Furthermore, in addition to determining the position of the mobile terminal 100 based on the ground surface, the position of the mobile terminal 100 can also be determined based on the relative relationship with the user. For example, the mobile terminal 100 can be provided with a camera for photographing the user, and the relative relationship with the user can be determined by determining the orientation of the user's face. Therefore, even when the user lies down and operates the mobile terminal 100, the vertical / horizontal state of the mobile terminal 100 can be determined in relation to the face, and an antenna corresponding to the state can be selected. Moreover, you may make it judge the antenna (receiver) to be used based on the position of the hand holding the portable terminal 100, without judging a face.

  The CPU 111 determines the position and direction of the portable terminal based on the wave of the signal from the GPS (S807). The position and direction determined by the communication unit (not shown) are transmitted to the content server, and the content based on the position and direction is received (S808). Then, on the mobile terminal 100, the content transmitted from the content server in advance is displayed superimposed on the display 110 configured inside the lens in the real space viewed through the lens (S809).

  Further, the mobile terminal 100 can receive map image data via the NW, and store information (registered in the content server) associated with the position coordinates can be superimposed on the map. The map information received via the NW is updated according to the position of the mobile terminal at that time when the mobile terminal is moved. Also, it is desirable to adjust the coordinates in the content server and the coordinates of the content received via the NW. In addition, the superimposition processing of content such as map image data and store information may be performed on the mobile terminal 100 or a content server on the NW.

  Furthermore, on the display of the mobile terminal 100, the direction from the measured current position may be displayed by an image such as an arrow or characters.

  As described above, by using a plurality of antennas, even in a mobile terminal (for example, a mobile phone) in which the direction when viewing the display changes depending on the usage scene, the activation of the camera or the tilt of the mobile terminal is detected, and By changing the direction, the direction can be obtained and the AR application can be used.

  Next, a modification of the mobile terminal 100 in this application example will be described. In this modification, it is assumed that an indoor navigation system is constructed using four transmitters. This transmitter is a transmitter installed on the indoor ceiling in advance, and at least the ID of each transmitter (which can be determined from which transmitter) is included in the signal from the transmitter, and the transmitter is installed. The position information and the time when the transmission wave is transmitted are included. Any frequency can be used for the transmission wave. At least two antennas are provided as a receiver, and at least the antenna 101 and the antenna 103 or the antenna 104 must be provided.

  It is desirable that the two antennas are arranged in one device, and the device including the antenna can be made portable. This device is assumed to be a portable terminal, for example, that has a display laid down so as to be horizontally long.

  FIG. 15 is a flowchart illustrating processing of the mobile terminal 100 according to the modification. The waves transmitted from the transmitter are received by the respective antennas 101 and 104 (S901). And the absolute position (x, y, z) of the antenna 101 is calculated | required using the information of the wave emitted from four transmitters (S902). Next, the elevation angle and azimuth angle of the transmitter viewed from the antenna 101 are obtained (S903).

  Then, the phase of the wave received by the antennas 101 and 104 is obtained (S904). Here, if the frequency of the received wave is high and the phase cannot be obtained with the wave in the state where no processing is performed, the received waveform is multiplied by the radio wave in the frequency converter, and only the difference portion is extracted. (Down-converting) derives the phase.

  The phase difference between the waves received by the two antennas 101 and 104 is obtained from the phase of the received wave (S905). When the frequency of the received wave is high and the received wave is multiplied by another wave, a double phase difference is obtained. Otherwise, a single phase difference is sufficient.

  Then, a baseline vector between the antenna 101 and the antenna 104 based on the antenna 101 is obtained from the difference in path difference based on the obtained phase difference (S906). In order to obtain the direction from the antenna 101 to the transmitter based on the baseline vector, the initial value (reference) of the baseline vector must be known. Therefore, the initial values are set to (0, 0, 0) for the antenna 101 and (0, L, 0) for the antenna 104, and this initial vector is true north / horizontal.

  Then, the direction in which the mobile terminal 100 faces and the absolute position of the device are transmitted to the content server that stores the content in order to perform the content operation (S907). Then, in the content server, content based on the direction and position of the mobile terminal 100 is acquired, and the content is displayed on the display unit (S908). If a camera is used, the image data is combined with the image data.

  A three-dimensional virtual space is constructed in the content server, and text and image contents are arranged according to the coordinates (Xv, Yv, Zv) in the virtual space. Information on the direction of the device and the absolute position of the device obtained in steps S902 and S904 are associated with the coordinates of the virtual space.

  Then, the navigation system can be used even indoors by displaying it as it is on the mobile terminal that captures the video of the real space. Further, if the wave transmitted from the transmitter includes the ID of each transmitter, the position information of the transmitter, and the time at which the transmitted wave is transmitted, it can be used as a transmitter without using the GPS.

  If the position of the transmitter is fixed and does not move, the ID of the transmitter and the position are registered in advance in the server or the like, and even if the position information is not transmitted from the transmitter, if the ID is known, the server The position of the transmitter can be acquired by making an inquiry.

  In the portable terminal 100 described above, the camera 108 may be disposed on the back surface with respect to the display, or may be provided on a side surface portion of the portable terminal 100 as shown in FIG. In general, when operating the mobile terminal 100, the display surface is often parallel to the ground. Therefore, it is considered practically effective to arrange the camera at a position corresponding to the direction in which the user operates, that is, at the upper side surface portion of the mobile terminal 100.

  Below, the effect of the direction measuring device 20 of this embodiment and the portable terminal 100 provided with the same is demonstrated. According to the direction measurement device 20 of the present embodiment, the receiver position calculation unit 3 measures the current position of the own device based on the radio signals from the transmitters 11 to 1n, and the positional relationship calculation unit 4 determines the positioning. An azimuth angle and an elevation angle are calculated based on the current position of the device.

  Then, the phase determination unit 5 acquires the phases of the waves of at least two radio signals received by the receivers 21 to 2n, respectively, and the phase difference calculation unit 6 calculates the phase differences of the waves of the at least two radio signals. The angle calculation unit 7 measures the direction from the current position measured by the receiver position calculation unit 3 based on the azimuth and elevation angles calculated by the positional relationship calculation unit 4 and the measured phase difference. calculate. The receivers 21 to 2n are arranged so that the absolute value of the phase difference from each received radio signal wave is less than 0.5. As a result, the absolute value of the phase difference can be less than 0.5, the phase difference can be determined without considering the integer value bias, and the direction based on the phase difference can be determined.

  Further, according to the direction measurement device 20 of the present embodiment, at least three receivers 21 to 23 are arranged, the state determination unit 31 determines the state of the direction measurement device 20, and the phase determination unit 5 Based on the determined state, a combination of two receivers among at least three receivers 21 to 23 is determined. Then, the phase difference calculation unit 6 calculates the phase difference based on the wave of the radio signal received by the receiver whose combination is determined, and the angle calculation unit 7 calculates the direction of the direction measuring device. Thereby, an appropriate antenna combination based on the state of the apparatus can be determined, and an accurate direction can be calculated.

  The receiver of the direction measuring device 20 is capable of receiving radio signals from GPS satellites, and when arranged at intervals of 9.5 cm or less, the direction calculation using the GPS satellites is accurate. Can be done well.

  In the portable terminal 100 provided with the direction measuring device 20, the content stored in the content storage unit 9 is displayed at a location indicated by the direction / position based on the direction calculated by the angle calculation unit 7. Part 10 displays. Thereby, based on the exact direction. Content display processing can be performed on the real space, and accurate information, that is, the real space in which the content is synthesized can be provided to the user.

  Further, on the display of the mobile terminal 100, the measured direction from the current position may be displayed by an image such as an arrow or a character. Thereby, the compass can be substituted for the portable terminal 100.

DESCRIPTION OF SYMBOLS 1 ... Transmission part, 2 ... Reception part, 3 ... Receiver position calculation part, 4 ... Position relationship calculation part, 5 ... Phase judgment part, 6 ... Phase difference calculation part, 7 ... Angle calculation part, 8 ... Virtual camera operation part 11-1n ... receiver, 21-2n ... receiver, 31 ... status determination unit, 9 ... content storage unit, 10 ... content display unit, 100 ... mobile terminal, 101 ... antenna, 102 ... antenna, 103 ... antenna, 104 ... antenna, 108 ... camera, 110 ... display.

Claims (6)

At least two or more receiving means for receiving a wave of a radio signal;
Positioning means for positioning the current position based on the radio signal received by the receiving means;
Calculation means for calculating an azimuth angle and an elevation angle based on the current position of the device measured by the positioning means;
Phase acquisition means for acquiring the phase of each wave of the radio signal received by the reception means;
Phase difference measuring means for measuring a phase difference between two radio signals acquired by the phase acquiring means;
Direction calculating means for calculating the direction from the current position measured by the positioning means based on the azimuth and elevation angles calculated by the calculating means and the phase difference measured by the phase difference measuring means; Prepared,
The two or more receiving means are arranged so that an absolute value of a phase difference between a wave received by one receiving means and a wave received by another receiving means is less than 0.5. Direction measuring device characterized by. At least three receiving means are arranged,
State determination means for determining at least one of the inclination and movement of the direction measuring device;
Determining means for determining a combination of two receiving means among the at least three receiving means based on at least one of the inclination and movement determined by the state determining means;
With
The direction measuring device according to claim 1, wherein the direction calculating unit calculates a direction of the direction measuring device based on a wave of a radio signal received by the receiving unit determined by the determining unit. . The at least two receiving means receive a radio signal from a GPS satellite;
The direction measuring device according to claim 1 or 2, wherein the at least two or more receiving units are arranged at intervals of 1/2 or less of a wavelength of a radio signal from the GPS satellite. The direction measuring device according to any one of claims 1 to 3,
Content storage means for storing the content and the arrangement position in the real space;
Display means for displaying the content stored in the content storage means at a location based on the direction and position calculated in the direction measuring device;
An information processing apparatus comprising: The direction measuring device according to any one of claims 1 to 3,
An information processing apparatus comprising: display means for displaying a direction from a current position measured by the direction measuring apparatus. In a direction measuring device including a plurality of receiving units arranged so that an absolute value of a phase difference between a wave received by one receiving unit and a wave received by another receiving unit is less than 0.5 In the direction measurement method,
Two or more receiving steps for receiving a wave of a radio signal;
Based on the radio signal received by the receiving step, positioning step for positioning the current position;
A calculation step for calculating an azimuth angle and an elevation angle based on the current position of the device measured by the positioning step;
A phase acquisition step of acquiring the phase of the wave of the radio signal received by the reception step;
A phase difference measurement step of measuring a phase difference between two radio signals acquired by the phase acquisition step;
The direction from the current position measured by the positioning step is the azimuth angle and elevation angle calculated by the calculating means, and the phase difference of which the absolute value of the phase difference measured by the phase difference measuring step is less than 0.5. A direction calculating step for calculating based on
A direction measuring method characterized by that.

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