TWI288245B - Radio-based tracking system with synthetic aperture - Google Patents

Abstract

This invention relates to a method to increase the measure-accuracy of a radio-based tracking system having a mobile station and at least one position-fixed station, the method is characterized in that to detect the movement, which begins from an original position, of a mobile station by means of an absolute sensor technology and a relative sensor technology, to generate by means of the measure-data a virtual antenna in the form of a synthetic aperture, to be based on an application of the synthetic aperture so as to focus the mobile station on the position-fixed station and/or vice verse.

Description

1288245 IX. Description of the Invention: [Technical Field] The present invention relates to a radio-based tracking system having a mobile station and at least one fixed station, the tracking system being used in particular to determine the mobile station Spatial location. The invention further relates to a method for improving the measurement accuracy of a radio-based tracking system. [Prior Art] A radio-based tracking system is known to be achieved in various ways. For example, File [1] "Wireless Local Positioning" der Autoren M. Vos siek, L. Wiebking, P. Gulden, J. Wieghardt, C. Hoffmann und P. Heide provides a summary that has been revealed in Microwave Magazine des IEEE (Volume 4, Issue: 4. Dez. 2003, Page 77-86). The function of the radio-based tracking system is to switch the radio signal between the mobile station and a number of stations that are mostly fixed. Determining, based on the received radio signal, the relative distance between the mobile station and one or more fixed stations, or the relative angle between the mobile station and one or more fixed stations, or the mobile station and each The difference in distance between the two fixed stations. Based on these measurements, the spatial position of the mobile station can be determined by trilateration or trigonometry. The main problem with radio-based tracking systems is that radio signals must be widely propagated in a non-directional manner in space. This is required because the relative position between the mobile unit and the fixed unit (e.g., relative to the directional radio path) is not known in advance. However, the non-directional transmission of radio waves causes the signal 1288245 between the mobile unit and the fixed unit to be transmitted not only via the shortest direct path, but also, for example, on the wall" or on the object and therefore also via Transferred by an indirect path. Due to such an indirect path, the tracking result may be greatly distorted. This so-called multipath problem is particularly dangerous in internal area applications and is a decisive factor in the achievable accuracy limits of radio-based tracking systems. For example, as disclosed in the above document [1], there are a variety of applications in the internal area and in particular in the virtual physical area and automation technology, which requires high measurement accuracy. In addition, it is known that in order to improve the accuracy of the radio tracking system, various auxiliary sensors are used (for example, acceleration sensors, gyrators, taxis, compass sensors, tilt sensing). A linear, or angular encoder, etc.) is advantageous. Most of these auxiliary sensors are relative sensors, i.e., they do not determine the absolute position but determine a change in the starting position in a reference space. Most of these multi-sensors or hybrid systems operate on a moving model, so that the measurement information of different sensors (for example, in the φ Kalman filter) can be compared with the measurement data of the radio positioning sensor. combination. A disadvantage shown by the information technology point of view in the above system is that the individual end results are combined with each other to replace the original data of the respective sensors, so that information may be lost due to processing in each sensor. For example, if a wireless inductive detector determines an incorrect distance due to an important multipath condition, then such a highly erroneous flaw will enter the evaluation combination. By means of a mixed estimate, the error can be identified and/or reduced in some cases, but the original reference of the evaluation will continue to deteriorate due to erroneous measurements. -6- 1288245 SUMMARY OF THE INVENTION The object of the present invention is to further form a tracking system according to the preamble of claim 1 to achieve a high measurement accuracy and in particular due to further reflection. The measured distortion is reduced. The phenomenon of reflection occurs in addition to the direct signal transmission path between the mobile station and the fixed station. The above object is achieved by the method described in the independent patent application and the device described in another independent item. Other advantageous forms are described in each of the dependent items Φ. By the claimed method, by the movement of the mobile station from the original position (which is used to form a synthetic aperture), which is performed by absolute sensing techniques and measurement data of relative sensing techniques, The aperture or spatial extent (especially the antenna) can be mathematically expanded by relative sensing techniques and thus a synthetic aperture can be created. The present invention now describes a novel hybrid-tracking system and method in which the measurement data of the radio tracking system are combined in a particularly advantageous manner by means of the measurement data of the complementary relative sensing technique prior to delivery to further processing. With this method, interference can be effectively reduced by multipath-effects and is therefore an almost optimal combination of a relative sensing technique and a radio-based absolute sensing technique. More particularly, the present invention relates to a so-called time of arrival TOA (time of arrival) or round trip time of flight radio tracking system. In such an arrival time TOA system (eg GPS) 'by a single path between two stations - measurement of the running time - and in the flight cycle travel time RTOF by two paths between the stations - run time The measurement determines the distance between the stations. Particularly advantageous for these systems -7- 1288245

Embodiments have been described in the proposed GPS-system document or in US 52 1 6429, US 5,748,891, US 6, 549, 950, GB 1 605 409, DE 3 324 693, WO 200 1 67625, and in particular in Siemens) Application PCT/DE00/03 356, DE 1 9946 1 68.6, DE 1 0 1 5525 1.3, DE 1 0208479.3, DE 10 2004 017 267.6 or 10 0584 180.1, the contents of which can be referred to here [2] . In particular, an absolute sensing technique or radio measurement technique is required to create a measurement signal that displays the amplitude and phase of the transmitted signal based on the signal runtime or the length of the transmission path, as is generally the case at all speeds. The same is true in radar systems. Whether such display is continuous in time, discontinuous or only based on a limited number of pairs (multiple amplitudes, time) is not important. For the sake of simplicity, in particular all of the conceivable TOA- or RTOF-radio tracking-measurement modules (which provide the above-mentioned signals) are hereby combined under the circumstance of a secondary radar. The TOA system is certainly not a secondary radar under the guise of the ancient code, but the signals in the TOA-system·receiver station usually have the same form as the signals in the secondary radar in terms of appearance and information content. Therefore, a common way of thinking from the perspective of information and system technology is meaningful. The measurement signal of the above-described secondary radar (i.e., T0A- or RTOF-system) is hereinafter referred to as a measurement signal or an echo profile regardless of the detailed-signal form. The various maximum 値 in the echo shape correspond to a variety of different transmission paths with different signal runtimes. By the relative sensing technique, the direction and magnitude of the change in position relative to the original position of a mobile station can be quantified. The method of the present invention is based on a method of synthesizing pore diameters. The general principles of SAR Synthetic 1288245 aperture radar) have been described in detail in professional books, for example.

* Radar mit realer und synthetischer Apertur" von Klausing und W. Holpp (Oldenbourg, 2000) in Kapitel 8, S. 213 ff [3]. Almost the same method in meditation or tomography in medicine It is known in the field of ultrasonic measurement technology. For the description of the method of tomography, for example, "M. Vossiek, V. Magori und H. Ermert, "An Ultrasonic Multielement Sensor System for Position Invariant Object Identification" , its dry U in IEEE • International Ultrasonic Symposium, Cannes, France, 1 994 [4]. The conventional methods of the present invention are expanded with synthetic apertures to perform radio-based tracking in such a manner that instead of passively making a reflected signal that is interfering on any object processed into an image, Only the reflected signals received by different measurement locations are actively superimposed and then used as radio tracking. According to an advantageous embodiment, the synthetic aperture is used to generate a directional characteristic of the synthetic aperture by appropriately selecting the amplitude of the aperture and/or the amplitude-and/or phase-weighted 値 of the measurement data of the absolute sensing technique. The pattern is placed nearly uniformly across the error ellipse of the absolute sensing technique. This pattern is nearly evenly located in the range of error ellipses of position measurements previously made with any medium. According to a further advantageous embodiment, the synthetic aperture is used in another way by the known position of the fixed position of the station at an unknown position of the mobile station or by the operation of the synthetic aperture ( Especially by the imaging method of broadband holographic surgery). By the above method, an additional angle measurement 値 is generated for the distance measurement 値. -9- 1288245 According to another advantageous embodiment, another application of the synthetic aperture is to image the known position of the mobile station at an unknown position in the fixed position. According to an advantageous method or an advantageous device, the distance and angle information between a mobile station (especially a secondary radar) and a fixed-position station (especially a transponder) must be calculated. The steps of the method are carried out by means of a suitably prepared apparatus. According to an advantageous method or advantageous arrangement, the distance-and angle data of one or more mobile stations (especially transponders in secondary radars) are combined by a Kalman filter for one or more positions. The steps of the method are carried out by means of a suitable prepared apparatus. According to an advantageous or advantageous device, the stationary station (especially the transponder) is constructed as a passive rear diffuser and the absolute position determination is based on the distance and angle relative to the secondary radar. The various steps of the method are carried out by means of a suitably prepared apparatus. According to an advantageous embodiment, a series of steps are repeated to improve the decision on the position of the mobile station. According to an advantageous embodiment, an initial coarse focusing action is achieved by measuring the absolute- and/or relative-sensing technique. According to an advantageous embodiment, an initial coarse focusing effect is achieved by information of previous measurement data. According to an advantageous embodiment, the measured received signal Εη(ω) has to be theoretically calculated in order to calculate back or to image one of the first (especially fixed-position) points bU, y, z). The function Fn(an,r,o) is associated with the first station (especially the fixed-position station, which in the ideal case is a point-shaped reflector) from the second (especially the mobile station) measurement point an = (Xn, yn, ζη) τ produces this function Fn(an, r, co) at position 10 - 1288245 r = (x, y, ζ) τ. An advantageous device for improving the measurement accuracy of a radio-based tracking system (having a mobile station and at least one fixed station) is adapted from a plurality of different locations by means of a plurality of different location data to which the sensing technology belongs The echo shapes of the transmission paths are superimposed to produce a synthetic aperture in the form of a virtual antenna. According to an advantageous embodiment, at least two stations fixed in position are required to produce lateral data. According to an advantageous embodiment, the mobile station is formed by a secondary radar and at least one fixed station is formed by a transponder to create a "self-positioning" system. According to an advantageous embodiment, the mobile station is formed by a transponder and at least one fixed station is formed by a secondary radar to produce a "remote-positioning" system. According to an advantageous embodiment, a data transfer device has to be prepared for transmitting the data from the at least one secondary radar to the signal processing device. The invention will now be explained in accordance with an embodiment in the drawings. [Embodiment] The method of the present invention for positioning a robot arm in accordance with a sensing technique will be described below. Figure 1 shows this typical robot. Fig. 1 shows a first embodiment for positioning by means of a "self-positioning" system, whereby a method for improving the measurement accuracy of a radio tracking system can be described in a simple manner. In the "self-positioning" system, the original measurement unit secondary radar S R is located in the mobile device or in the mobile station, allowing the mobile device to determine its particular location. The fixed station is formed by forwarding the -11- 1288245 TP. Depending on the radio communication, other non-measurable side position information can also be used. AE represents an evaluation unit. The distance is represented by d. A denotes an antenna. The above design is shown in Fig. 1, in which the secondary radar SR is located on the animal body (here, for example, on the jig of the robot arm). Three transponders TP need to be prepared as a fixed station. The robot, for example, is additionally provided with a plurality of angle encoders RS 1, R S 2, R S 3 on each joint by means of a relative sensing technique RS, so that the direction and magnitude of the change with respect to the position of the original position can be quantified. The invention can be illustrated in terms of a so-called "self-positioning" system. In terms of absolute positioning, the rotary setters currently available within a reasonable cost range are not accurate enough because their errors accumulate in a wide range of operating paths. In addition, inaccuracies are often caused by mechanical deformation. A typical device/system with a relative sensor thus provides 1) a good repeatability accuracy, 2) a good accuracy with respect to small changes in position, 3) but freedom through a large range The absolute position of the defect when moving. In particular, the above problem 3) can be solved by using the above-described nature 2) in the present invention and in combination with the aforementioned radio tracking system. The above properties 2) of the present invention are used in the following manner: a synthetic aperture is created by the movement of the mobile system. What is important here is that it is not necessary to identify the absolute position of the antenna A of the secondary radar SR. It is sufficient to calculate the synthetic aperture from the relative coordinates of the aperture support point to any reference point (for example, the measured starting point). A variety of different sensors provide such information in an advantageous manner. -12- 1288245 When we use a secondary radar to combine with mobile to form a synthetic aperture, it can also be very sharply calculated in the future (in general radio tracking-individual measurement compared to In the case of almost non-directional wave propagation, the radio signal is focused almost at any point in space, ie, computationally, a situation arises: whether we have performed an actual antenna that is sharp enough to the transponder in the direction. measuring. It is known that the use of a sharp-eyed antenna greatly reduces the multipath problem. Since the position of the repeater is unknown at the beginning, it is usually not possible to directly focus on the repeater during the calculation. A synthetic pore size in the present invention is used in two different ways. Mode 1 By means of the sensing technology used, the relative sensing technology and/or the radio positioning sensing technology or the absolute sensing technology performed in a basic manner according to the prior art can be at least roughly determined under all the criteria. The location of the repeater. According to the first mode, a typical error ellipse can be estimated which indicates the desired error range for position measurement. Therefore, we can start with a certain reliability by "the repeater is stopped in the interior of the space sector at a certain place", wherein the sector is described by the measurement 値 and the error ellipse. The transmit-/receive direction of the synthetic aperture is now calculated to be aligned with the previously roughly measured dwell position of the transponder. By appropriately selecting the size of the aperture and, if necessary, by appropriately weighting the amplitude of the measurement signal, it is additionally possible to make the pattern of the synthetic aperture almost uniform over the range of the error ellipse and thus preferably It is greatly attenuated in the angular range beside the error ellipse, which has only a small submaximum 値 in this angular range. In the synthetic aperture, how to generate a certain directional characteristic by the size of the aperture and by the amplitude-and phase weighting of the received signal-13-13288245 has been well known to experts of this class, for example, see The above-mentioned document, g卩, must produce a virtual antenna that is as sharp as possible in the direction but must be pointed to the same as the misalignment required for the unpredictable pre-predictive information. The multipath error can be greatly reduced when the direction sharpness is improved during wireless transmission. The improved measurement signal generated by means of the synthetic aperture can then be transmitted completely and normally to the position normally in the superior position according to the prior art. Algorithm. The above method must be used on at least two transponders for spatial localization in order to obtain the required lateralized data. In order to improve the above-mentioned pre-information, that is, in order to make the direction more sharply focused, The call information is measured in the measurement performed later. The predicted new stop position can be predicted, for example, by means of a Kalman filter. The size of the error ellipse is estimated. Mode 2 The second way to determine the position of the transponder is to perform an image setting, that is, to image the transponder present in the space by means of the moved secondary radar. In the image area b(x, y, z), since the image area has a reference 已知 which is known to the position of the secondary radar, the secondary radar can directly determine the transponder by the imaging of the transponder ( Its relative position in the fixed position and thus its absolute position can be determined in space. Advantageously, it is theoretically sufficient to image only one transponder in a suitable two-dimensional movement of the secondary radar. It is used to determine the three-dimensional spatial position of the secondary radar. This is advantageous for some applications where it is not possible to form a good trilateral measurement basis due to cost or coverage. When determining the distance and direction of multiple transponders, these ports can be fully and normally transmitted to the positioning algorithm that is usually in the superior position according to the prior art of any of the-14-1288245. For imaging, the synthetic aperture-method and algorithm can be used for all known image settings. Another similar positioning application is shown for clarity in Figure 2. In addition, the configuration and method of the present invention It can also be transferred to all other applications, for example, to a configuration formed by a motor vehicle, forklift, crane, mobile terminal (eg, mobile phone, laptop, etc.). In order to image the transponder TP, synthetic aperture-methods and algorithms for all known image settings can be used and transferred to current applications. A method for so-called wide-band holographic imaging will be shown below. One form is used as an embodiment. Figure 3 is used to illustrate a spatial situation. As shown above, data reception is performed such that the secondary radar emits a signal from the position an = (Xn, yn, ζη) τ, respectively. In order to be able to display the entire summary, it is first possible to start with the "secondary radar receiving the signal sent back by the repeater at the same position an". The transfer to a configuration with separate transmit-and-receive antennas can be easily achieved, for example, by the above-described documents. This measurement process should now be performed by M (an, n = l ... M) different measurement locations. Therefore, this measurement yields a set of different measurement signals (echo profiles), which are referred to below as en(t) or as the spectrum Εη(ω) to which they belong. The actual position of the repeater, which is ideally determined by measurement, is Ptp1 = (Xtpi, yTP1, ΖΤΡ1). In the case of a specific display, starting with a further simplification process: - the measuring range (where the transponder can be left) is limited in a spatial area 'where it can be ensured that this transponder can be used by all positions an -15- 1288245 to measure. • Start with a fixed orientation characteristic of the same form of all antennas that is independent of direction. - The reference used to model the transmission channel is an ideal AWGN-channel. That is, the echo shape en(t) received by the radar can be described by a model in which the transmitted signals are weighted by p amplitudes and the time delayed signals are superimposed in a linear manner, and the index P represents various differences. The transmission path from the secondary radar to the repeater and back again (direct path and multipath path).

P e n (t = α n · $ a p · s (t - τ η - τ p) + η (1)) Ρ = \ where α η is the nth characteristic decay constant for each measurement. Ρ is the attenuation of each path of the p transmission paths via normal fundamental attenuation. Τη is the characteristic signal running time (β卩, the signal running time of the shortest direct path from the secondary radar to the repeater and returning) when measuring. Ρ is a possible run time delay for each path of the p transmission paths due to multiple reflections. n(t) describes the various superimposed interferences (additive white Gaussian noise AWGN). After the above equation is converted into a transmission model in the frequency domain, you can get:

En(co) = ou. Left aP.S(co).e j0) Tn.e j0i.Tp + N((〇) corpse=1 for any spatial point r = U, y, z)T and return The basic running time τ „ is calculated according to the following formula: and k | = = ^J(x^Xn) +(y^yj +(z^Zn) -16- 1288245 where C is the transmission rate of the wave. The reconstruction algorithm is performed according to the form of optimal filtering. In order to calculate the image point b (X, y, z), the measured received signal Ε η (ω) must be a function of ί里论Fn(an , r, co) to be associated, this function Fn(an, r, co) is viewed by the measurement argument an = (xn, yn, ζη) τ by a transponder (which is ideally a dot shape) The reflector is generated at position r = (x, y, ζ) τ. The correlation/comparison function described above provides only a large 値 when the received signal approximates the theoretical signal, when the transponder is actually located This is the case when the position r is above. At this time, the received image point r actually corresponds to the position of the transponder Ρτρΐ = (χτρι, y Τ Ρ 1 , Ζτρι) D. By all the measurements The sum of the results produced has a chance, Indicates whether there is a transponder at position r. The reconstruction equation is as follows: Μ Εη(ω) • Fn'1(an,r = (x, y, ζ)τ,ω)άω b(x, y , η-\ω

Here, the inverse filter selected for signal comparison (according to the associated method) corresponds to the commonly used matched filter combination for the exponential expansion (ie, with the conjugate complex (ie, F/(an) ,r,co)) Multiply). According to the previously described transmission model and under the interference of ignoring the addition, the virtual transponder signal Fn(an, r, co) becomes at r:

Fn(an,r,o) =金 ou.aP.S(co).e-jto.T'e-jto." corpse=1 In addition, it is still assumed that this transmitted signal is S(co = l), which is The general validity is not limited, as the possible undesired characteristics of the transmitted signal (at least in the transmission area of interest to us) can be achieved by the combination of the above inverse filters. Compensation. In the above-mentioned reconstruction formula, if the above signal hypothesis is used, then -17- 1288245 is obtained:

b (x,y,z) = [ JE n (ω) · Ζ α n. ex P · e ω ' (τ η + τ p) · d ω I η=\ω corpse=1 if replaced by t Τρ + τη and the sum of p (sum) marks before the integration is integrated, then it can be known that the integral of the angular frequency ω corresponds to the inverse Fourier transform and thus can provide a time point 1 = τ Ρ + τη receive signal. Since the signal path τ 都是 is unknown except for the direct path (where τ Ρ = 0), the signal model can be reduced on this path. The final reconstruction equation is as follows: Μ b(x, y, z)= I ^ en(t = Tn) | /7=1 It must be noted that the actual received signal must be expanded before being added to a complex signal. In order to determine the envelope curve of the image function (ie, it is in the form of a luminance function). The calculation of the complex signal can be achieved by means of a Hilbert transform. The expressions obtained can be explained very clearly. In fact, if the transponder is located at position r, its answer signal will occur in the echo shape en(t) at the time point ΐ = τη. By correct addition of the running time on one measurement path, the signal contribution degree can be superimposed in a coherent manner by the equation for reconstruction, so that b(x, y, ζ) is larger. . Other signal components of the transponder that are not located in r, the signal components or noise of the multipath reflection are superimposed on each other, and a much smaller image signal is caused due to inconsistent running time and non-coherence. In order to make the super-coherent superposition of multiple echo signals reliably produce small amplitudes, the number of measurement points cannot be chosen to be too small. An interesting side effect of mode 2) is that the transponder does not have to be operated in a time-, frequency- or code-multiplexed manner. In a typical radio tracking system, the signals of the transponders must not interfere with each other or the superposition of multiple transponders -18- 1288245 signals in the measuring station will not cause erroneous results. The method of the present invention provides a so-called spatial division multiplex access in an intrinsic manner. Therefore, when the transponders are separated from each other in position, they are separated from each other in position by imaging by synthesizing the apertures, and they can also be distinguished from each other without other encoding. So far it has been started with a configuration of "self-positioning". Since the correspondence of radar coordinates with respect to the transponder is generally involved in the method of the present invention, it is apparent immediately that such a configuration can also be converted into a remote positioning system. The method of determining the position of the fixed secondary radar is achieved by the aforementioned coarse decision of the absolute position of at least one secondary radar, that is, after all the secondary radars have been imaged in the image area. This is achieved by a decision relative to the position of the "absolute position of the only repeater that has been stopped." Figure 4 is another possible embodiment of a radio tracking system whose measurement accuracy is improved by the method of the present invention. The difference between Fig. 4 and Fig. 1 is that it shows a remote positioning system. In a remote positioning system, a stationary station can dictate each measurement unit (SR) and thus externally determine the location of a mobile device or mobile station (TP). In this system, other non-measurement side position information can be used depending on the radio communication. In the above case, the information of the relative sensing technology is transmitted to the fixed position secondary radar or the echo profile must be transmitted to the central evaluation unit, wherein the evaluation unit performs the information of the relative sensing technology by one of the above methods. . Some basic formulas for determining the dimensions of the system are shown below, with each parameter shown in Figure 5. -19- 1288245 Since the synthetic aperture method is based on the superposition of the coherence of the measured signals, the conditions required to use this method are: the deviations from each other 値Spos of all measurement positions an = (Xn, yn, Ζη) 必须 must be known when it is much smaller than wavelength 1. If such conditions are not met, then an appropriate parametric superposition of one of the signals is not possible. For example, the general requirements are:

s λ C 0 P 0 s <—< --- 8 persons·8 where f m is the intermediate frequency of the measurement signal. In order to estimate the resolution desired for wide-band holography, the following equations can be found in various documents. The horizontal resolution (for illustration, see Figure 5) is: D, fm The axial resolution (for illustration, see Figure 5) is: δ a X ~- △/ where the variable definition used As follows: Z0: the average distance from the aperture surface to the receiving area, D: the length of the hole, c: the transmission rate of the wave, fm: the intermediate frequency of the measurement signal, Δf: the bandwidth of the measurement signal. The following will consider the characteristics of a system with an intermediate frequency of 5.8 GHz and a bandwidth of 100 MHz. This system is used in the robot in Fig. 1: the working area of this robot is limited to a space area where z〇 is at most 4 meters. By moving the robot arm, a 20 cm synthetic aperture can be constructed. In the above case, the achievable 1 m lateral resolution is much better than the axial resolution. The axial resolution in a typical radio tracking system is a decisive feature based on a -20- 1288245 runtime principle. If it is considered that the accuracy of the positioning achieved by the interpolation method is less than the resolution number: an order of magnitude, it can be estimated that the method according to the invention will only cause a few centimeters of measurement on the transponder. Unreliable". Measurement reliability in the millimeter range or sub-millimeter can be achieved by a combination of radar to multiple transponder measurements and/or a combination of multiple secondary radars to a transponder. The need for measurement accuracy of relative sensing techniques is based on the above-mentioned absolute absolute 5 5 pqs < 6.5 mm, i.e., relative to 3% of the aperture size, which is a suitable requirement for a typical rotary setter. Secondly, the working range of a 43 3 MHz system motor vehicle for positioning a motor vehicle will be considered to be limited to a space region, where z. The maximum is meters. By the movement of the motor vehicle, a 1 meter synthetic hole can be formed to meet the measurement accuracy of the relative sensing technique. In this case, the size is 10 cm, that is, the relative enthalpy relative to the aperture 値 is less than 1. 〇% can be achieved with a general meter and steering sensor. The last example can also be transferred to a mobile phone carried by a person (for example, a laptop, a broadband local network, a Bluetooth, a mobile device, etc.). In this case, an acceleration sensor or swivel is used as the relative sensor. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a first embodiment of position determination (self-positioning). Figure 2 is a second embodiment of position determination (self-positioning). Fig. 3 is a fourth embodiment for determining the position (distal positioning) of the position of the fourth image by the wide-band holographic imaging method. This kind of ί to 2 each of the two at least the scope of the 値 is. Machine 100 diameter. Approximately, this terminal wireless device can be used to solve the resolution of the resolution of the wide-band holographic imaging method from Fig. 5 to Fig. 5. [Main component symbol description] TP, TP1~TP3 repeater SR, SR1~SR3 secondary radar RS, RS1~RS3 angle encoder

AE evaluation unit

twenty two-

Claims (1)

Radio-based tracking system with synthetic aperture 1288245 ra No. 94384411 (amended in March 2006) X. Patent application scope: • 1 · A method for improving the measurement accuracy of a radio-based tracking system ( The method has a mobile station and at least one fixed station. The method is characterized by: - determining the 0 of a mobile station by the absolute sensing technique and the relative sensing technique, starting from the starting position Moving, - generating a virtual antenna in the form of a synthetic aperture by measuring the data, and - focusing the mobile station on a fixed position using the synthetic aperture and/or vice versa. The method of claim 1, wherein the directional characteristic of the synthetic aperture is generated by appropriately selecting the magnitude of the aperture and/or the amplitude-and/or phase-weighted 値 of the measurement data of the absolute sensing technique, such that the pattern is almost Uniformly located in the range of error ellipses measured at any previous position. ® 3. As in the method of claim 1, another way The synthetic aperture is used by the calculation of the known position of the fixed position of the station at an unknown position of the mobile station, which is achieved by an imaging method formed by a synthetic aperture, in particular by wide frequency 4. The image processing method is used to achieve 4. As in the method of claim 3, the other way is to use the synthetic aperture by calculating the known position of the mobile station at an unknown position of the fixed station. 5. If the method of any one of claims 1 to 4 is applied, the calculation of S) The mobile station, especially the secondary radar and fixed-position stations, especially the distance and angle information between the transponders. 1288245 6 • The method of claim 5, wherein one or more mobile stations are combined by one or more positions, in particular the distance-and angle of the transponder in the secondary radar data. 7. The method of claim 5, wherein the fixed position, in particular the transponder, is constructed by a passive backscatterer, and the absolute position is determined based on the distance relative to the mobile station, in particular the secondary radar. And angle to achieve. 8) The method of claim 6, wherein the fixed position, in particular the transponder, is constructed by a passive backscatterer, and an absolute position is determined based on the distance relative to the mobile station, in particular the secondary radar. And angle to achieve. 9. The method of any one of claims 1 to 4, wherein the steps are repeated to improve the position of the mobile station. 10. The method of claim 2, wherein the initial focusing effect is performed by a measurement of absolute-and/or relative sensing techniques. #11. The method of claim 2, wherein the initial focusing is performed by the measurement previously performed. 1 2 · If the method of claim 3 or 4 is applied, wherein the first point b(x, y, z) is calculated back, so that the measured received signal Εη(ω) can be theoretically a function Fn(an,r,o) is associated with the first (which is ideally a point-shaped reflection benefit). The measurement point of the brother-^ station, especially the mobile station, an = ( X η, y η, Zn This function Fn(an, r, 〇) is generated at position r = (x, y, z)T when viewed in T. 1 3 · The method of claim 12, wherein the equation for reconstruction is: b (X, y, z) = LJ Ε η (ω) · [ a n. α p · eJ - ω . (τ n +τ P) · d ω |. -2 - 1288245 "·If you apply for a patent... item, the last formula used for reconstruction is: Μ b(x,y,Ζ)= I Σ en(t = Tn) Bu 1 5 · A device for measuring the accuracy of a radio-based tracking system having a mobile station and at least one fixed station 'This device is characterized by: a) - at least one secondary radar and at least one type of forwarding Absolute sensing technique produced by the device, φ b) at least one relative sensing technique used to quantify the number and direction of changes in the position of the mobile station relative to the original position. c) A signal processing device, It is used to jointly process measurement data measured by absolute sensing technology and relative sensing technology to produce a virtual antenna in the form of a synthetic aperture, and d) a focusing device based on a synthetic aperture The mobile station is focused on the fixed position and/or in the opposite direction. 16. If the device of claim 5 is set, at least two fixed positions are set. • 1 7 · If the patent application is the first 5 or 16 items Apparatus, wherein the mobile station is formed by a secondary radar and at least one fixed station is formed by a transponder. 1 8 · A device of claim 15 or 16 wherein the mobile station is transponder The apparatus for forming and at least one fixed position is formed by a secondary radar. [9] The apparatus of claim 17, wherein the data transfer apparatus transmits the data to the signal processing apparatus by at least one secondary radar. Such as the device of claim 18, wherein the data transfer device enables 1288245 is transferred by at least one secondary radar to the signal processing device g 2 1 . As in the device of claim 15 or 16, the device is used to perform pre-information on the position of a fixed position. 22. Apparatus according to claim 15 or 16, wherein one of the RTOF (round trip time of flight) or a r r i v a 1) radio positioning system. =1 Kalman filter, wave rough forecast, this tracking system is TO A (time of