Planning of cellular radio networks, using digital photogrammetry in conjunction with a reference database of the absorption and reflection characteristics of different building and vegetation types previously identified

The invention relates to an apparatus and a method for microcellular radio network planning by terrestrial digi taler Photogrammetry and an orientation platform, these comprising a digital image recording device and a sa tellitengestütztes attitude determination system (DGPS) according Oberbe handle of claim 1.

is from the German patent application 197 35 175 A1 A method for digital capture of spatial scenes and to Determination of object coordinates known, according Dorti ger solution in a simple manner any natural scenes to be detected by single position shots, oh ne that a priori control points or a uniform Koor must be specified coordinate system. Furthermore, should the on Based on the thus detected scenes subsequently a geometrically dimensional image to be created, which in turn in a relevant database is transformable.

According to the approach according to DE 197 35 175 A1, the inter essierende scene from different positions z. B. with received a digital camera, the image obtained data are stored in appropriate files. In connection thereto are corresponding reference or link elements in the individual recordings determined, and this also can be carried out interactively. The reference or Verknüpfungsele elements may be trademarks, arranged in the respective scene are, or represent distinctive points from the Scene image or scene images themselves originate. The Aufnah me or the recording sequence can either continuously out discontinuously, ie in the form of individual Screenshots be made. The obtained digital records who the automatic determination of the inner space Geometry of the system of linking elements subjected wherein in known methods of digital video and / or Mu edge detection is resorted. In addition to the possi probability exist that external coordinates or control points are provided in order to optimize the image synthesis. that there presented method is preferably used archaeo detection logical excavation situations, ie Derar for documentation tiger excavations. The processed image data of serve creation of a 3D model, this then a ideal means of documentation exposed finds is.

The DE 43 38 280 C1, in turn, discloses a method for image-based position sensing and mapping of underground, near-surface objects with an optical measuring device and geophysical sensors for detecting, evaluating and In pretation of geophysical data. With a high-precision Finding device in conjunction with an orientation platform is a continuous, three-dimensional and accurate plan Position determination is made, the relative position of the co ordinatensysteme shall be recognized with high accuracy. upper ground and underground object data is then in a processed central computer and subsequently to a for digital map systems transmit appropriate format and brought to view. The necessary sensors and there However, exact positional coordinates respectively mapping results considerable expense with a corresponding incorporated restricted field of application.

In DE 197 46 639 A1, a method for digital He abstract spatial objects and scenes for a 3D image map disclosed are easily any natural be detectable scenes by individual position shots without that a priori control points or a uniform Koor must be specified coordinate system. There is verfahrenssei tig to obtain a dataset for 3D image maps on already This digitized aerial photographs of the real Whether resorted objects or scenes or there are such Recordings made. The digitized aerial photography who assigned to the precision position coordinates, so that the ge wish positional accuracy for subsequent combination is given with other image data sets. Ready-made terre strische recordings of real objects or Sze concerned NEN provide views from different positions and / or directions, so that in particular the surface which can not be deduced from the aerial photographs, as comple zender image data set is present.

Ausgestaltend is according to DE 197 46 639 A1 noted that the scene of interest from different positions , Z. B. can be taken with a digital camera, wherein the image data obtained in the corresponding files from be placed. Following this, corresponding Re ference or linking elements in the individual recordings determined, this can also be interactive. The Refe ence or link elements may also be trademarks, the are arranged in each scene, or striking represent points that are from the scene image itself. The obtained digital records are automatic Determining the internal space geometry of the system of subjected linking elements, for which purpose known Me are used methods of image processing.

With increasing population density and the expansion of wireless networks the cellular network planning continues to gain in importance. In urban areas and cities where lead existing Ge building, the different surfaces with different have reflective properties to field distortions due reflection and absorption of high-frequency energy. It is now known to use 3D terrain models as primary data to MEDD models propagation simulation durchzufüh ren. The existing data on a building and / or vegetation inventory in urban areas, however, are not sufficient, vorzuneh a highly accurate microcellular radio network planning men.

From the foregoing, it is therefore an object of the invention to provide a Apparatus and process for microcellular radio network to planning with a special orientation platform give the orientation platform known per se digital image recording device and a satellite-supported tes attitude determination system comprises.

The about-creating device and the process to be to a semi and / or fully automatic image acquisition ge equipped, at the same time there is the possibility a RF reflection situation grasp. should supplement the method and the apparatus includes a classification of Ge buildings or reach terrain or vegetation situations the basis of which to be expected with existing picture recording Reflection behavior can be assigned.

The object of the invention is achieved with an on direction according to the features of claim 1 and with a method in its definition of claim. 2

According to the device-side aspect of the invention is on a non-ferromagnetic, stable plate serves as a support, arranged an assembly, wherein the construction unit the digital image capturing device, such. as a digi tale camera, and this immediately adjacent a DGPS Receiving unit and a RF transmitting and receiving unit for having reflection detection. Further comprises the structural unit Sensors for determining the spatial orientation and ei NEN looking in receiving direction laser rangefinder. A control computer is connected via appropriate interfaces with the Sensors connected and receives orientation and angle data of the current position of the imaging device. Considering predetermined orientation tolerances is then with the aid of the control computer or an image pickup triggered a recording sequence, the image data together with the corresponding orientation and angle data on measure moments and the detected Reflexionxdaten in a Spei storage unit are stored.

The individual components in design and compass Inclinometers to determine the spatial orientation may include, be radio from said control computer tional activated, the control computer additionally Bildda th and the associated position and orientation data minde least temporarily stores it in a suitable memory.

The differential GPS positioning system is , Established from a known per se to a fixed point Reference station to a radio modem correction data exact positioning of the mounted on the plate DGPS receiver unit sends.

In one embodiment, the plate consists of a solid aluminum material, the image recording device and the aforementioned laser rangefinders are designed that a fast mounting. Suitable Positionin reNCy and fasteners ensure that the relative position of the sensors to the base plate do not change changed.

The above-mentioned aluminum plate, the individual components the device transmits can fitted with the latest with a device be switched, but the installation on standard tripods or z. B. allowed on a roof of a vehicle.

In continuation of the invention, the plate having a motor step drive for movement and orientation of the camera and / or the RF antenna of the transmitting and receiving unit ver be prevented, said drive target data for setting receives from the control computer.

To compensate for ferromagnetic and / or non-magnetic interference is the electronic compass with a calibration Winkelabwei interact, so that can not be avoided cations are reduced to a minimum.

The DGPS receiver unit has a GPS antenna and a Realtime GPS computer on, the latter via a serial Interface connected to the aforementioned control computer is.

The GPS computer is connected to the said radio modem, which for the safe design of the DGPS-reference path a winning afflicted emitters preferably with an antenna gain having ≧ 5 dB.

The real-time GPS computer is in a preferred Ausfüh ment of the invention, a position update rate of 5 Hz have.

In a further inventive embodiment, the DGPS reference path either via a radio link small Performance in this shared frequency range or over constructed a public mobile telecommunications network will.

The method, will now be using the Prior shown device for terrestrial digital photogrammetry a running query the data of DGPS receiver unit, the Sen sensors for determining the spatial orientation and the Rangefinder and associating and storing these Data as initial values ​​of exterior orientation of each individual NEN image made. are the existing control computer then control or recommendation values ​​for triggering the PageUp receiving device respectively of the digital camera to Erstel len Next from pictures, in which with the acquisition of the image data a sequence memory at the same time the corresponding storage and orientation data for the projection center and the Alignment of the image pickup device are stored. Further, on the basis of the obtained data packets temporally downstream of a known correlation methods used to enable a 3D modeling.

With the help of specially designed orientation platform can an almost blanket detection of the scatter and Re flexionsanteils radiated high-frequency power from the made irradiated area of ​​the building or the facade will. This is of course the possibility primarily referring to the determination of the reflection data, wherein the image recordings create a classification database serving. Following can be a typical Refle xionsverhalten after each typical situations for the subsequent simulation for radio network planning can be used.

Such reference database includes from exemplary Measurements obtained scattering / reflection properties of proto typical facades, z. B. a timbered house, a brick stone, concrete reinforcement, a steel and / or Glaskon struction and so on, wherein the measurements certain Type classes are assigned.

For the comprehensive determination of reflection own sheep th could then z. B. from existing photographic Aufnah measures which have been obtained with the platform or as Da source of data already exist, belonging to Ty penklasse be estimated. Also can therefrom the per to piece Plated centage prorated area ratio masonry th and thus identify highly reflective windows to pre-reflective review.

The transmitting and receiving unit is in a position to the respective to determine radio cell or a change of radio cell and, where appropriate, the detected reflection data online to the grid operators driver to pass, with the data in this case, sensing th spatial orientation of the orientation platform to Reflection data are allocated accordingly.

The control computer is connected to a monitor connected, which is capable, menu supported current image data and storage and provide guidance values, so that a manual Triggering a further image recording on the basis of bereitge is presented recommendation values ​​possible.

occurs when evaluating the position and orientation data a Kalibrierungsschtitt to compensate for the mechanical kon struktivbedingten position differences between the GPS Antenna of the respective receiving unit of the image plane of the Image recording device and the orientation differences between the latter and the electronic compass and the Rangefinder.

Considering the current positional and orientation data can be determined, the time at which the next Recording and / or measurement is to be triggered, said time point appears as a message on the user interface and / or a next receptacle and / or measurement at this time fires with automatic.

Additionally can of software, a program module for Kali bration of the image pickup device, respectively camera be provided, one for carrying the calibration take calibration target from different positions is. Using the resulting images will be on with recourse a so-called photo Modeller a one parameter determination finally determined the position of the image principal point, the corresponding calibration largely automatically runs.

As mentioned above, when recording the orientation data ei ne correction of existing ferto- and soft magnetic disturbances gen made.

To stabilize the photogrammetric evaluation, but also for control purposes proves the proposed Ent distance measurement between the center of projection and out selected points of the object surface to be advantageous. Of the Meßwegdurchmesser the rangefinder is relevant Use cases, ie a distance image capture device / Object in the range of 30 to 60 m in the order of 1 to 3 pixels.

By using the rangefinder is an automatic Identification of the image coordinates of the Lasermeßflecks electronic camera image in the sense of an automatic passport point extraction to determine the angular divergence between optical axis of the camera and the laser beam is possible.

The invention is described by way of Ausführungsbei explained, game and with the aid of a figure will.

The in <b>Fig.</b> 1 block diagram shown the orientation platform is based on a central control computer or Platt form computer from which via suitable interfaces, z. B. SCSI with the imaging device, namely a digital Camera, or the laser rangefinder over a serial Interface and the electronics for the pitch and Kom paßsensor communicates.

In addition, the platform computer data exchanges with a GPS computer from the DGPS receiver unit.

This DGPS receiver unit includes a wireless modem with a to order radio antenna and a GPS receiver with a respective GPS antenna.

Over the radio modem of the DGPS receiving unit is a DGPS Reference distance, ie, a radio link to a GPS Refe ence station, which at a precisely known location positio ned, constructed.

The DGPS system offers the possibility of a more precise Posi To achieve tion gathering by the system error of the egg tual satellite attitude determination system Corridor be cor-. Here, in the above-mentioned GPS reference station resorted beginning at a precisely surveyed point stands. This will determine the system error, z. B. the clock error the satellites, ionospheric and tropospheric runtime error and so on, these corrections and provides this Kor rektursignal on reference spark gap the GPS computer located on the plate the orientation platform to disposal. The errors are corrected by comparing the exact, known position of the reference station with the Position by means of the actual satellite reception signals was calculated. A receiver internal processing the satellite signals and the correction data received it enables an accurate determination of the position of the orienta tion platform to the centimeter range.

At least the GPS receiving antenna, the digital camera, Laser rangefinders and inclinometers or Compass sensor located on a non-ferromagnetic Plate which forms a support for the individual assemblies. The GPS antenna or a complete DGPS receiver unit with Antenna is the digital image recording device, that is, the digital camera placed as close together.

Enclosure Using the sensor system described above Lich of DGPS system, a position of the platform finally be their angular position and allow the camera direction be true. The control computer receives data from the Senso ren, which put him in the position, the current position to determine the image pickup means, taking into account predetermined orientation tolerances PageUp trigger or corresponding acquisition or recording sequence bereitzu trigger signals to the camera operating manual put. The image data are then shared with the associated orientation and angle data of the respective Receiving torque stored in a memory unit and for the further image processing is provided.

There is also the possibility that the computer platform or a tax calculator target data for a motor on drove to the orientation of the camera or the entire platform provides, so that an automatic tracking, z. B. in desired 360 ° images, is possible.

It has been shown that the reference spark gap with respect to Signal transmission reliability attach great importance is such that preferably here winning afflicted with a radiator Antenna gain ≧ 5 dB are used. The GPS computer is a real-time device with a position update rate ≧ 5 Hz to be executed.

The digital Kame used for the image pickup device ra should an image size in the range of at least 1000 × have 1500 pixels and for mobile use, ie for Images from the movement be suitable. furthermore has a way of adjusting and controlling the image recording can be provided via a control computer.

A calibration device or a software-reali ized calibration module is capable of faulty Win to correct the kelangaben Kompaßsensors. Here at commercial Kompaßsensoren internal filtering and Cor correction disabled and uncorrected magnetometer values special external correction supplied. It will next corrected values ​​for the K and Y components, in which caused by twisting and tilting not distorted mixtures are mathematically eliminated. Thus, there is a quasi artificial, precise horizontal alignment of Kom passes as follows.

The platform computer controls the transmission and Empfangsein unit, which is in communication with a GSM antenna. With Hil fe the transmitting and receiving unit is the specific Refle xionsverhalten determined. The data obtained in Kor relation to the stored image recordings. The each he took the 3D image recording sequence and the associated Reflexionsda th then allow an evaluation of the high-frequency self-sheep th or the high-frequency behavior in the radio cell, if there users of mobile telecommunications systems active are. With a host of evaluated data simulation models be created which have improved micro cellular radio network planning permit.

Characterized in that the orientation platform on a motor driving convincing mounted quickly is able to streets, squares or the like to depart, can in a very short time be determined to what extent the properties of facades or buildings, the high frequency situation for establishing secure influence or beeinträch telecommunication links term, turn bezüg resulting in a more accurate planning Lich of establishing repeater or other reception and transmitting stations within a mobile network.