JP2006349523A - Device for estimating circulating satellite orbit element, and method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of measuring a time-serial change in an arrival direction of a radio wave from a circulating satellite, and of estimating an orbit element of the satellite, based on a data therein. <P>SOLUTION: A step track tracking processing part 40 measures a reception level of the radio wave received by a reception antenna 10, by a reception part 30, and controls the reception level to maximize it, while changing an antenna directive direction by an antenna control part 20. The arrival direction of the satellite radio wave is recorded together with a measuring time, an orbit element estimation processing part 50 determines the orbit element to minimize an error between a measured result and a result calculated by the estimated orbit element, and a display part 60 displays a result thereof. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method and apparatus for estimating and displaying orbital elements of orbiting satellites from only the time and direction information obtained by measuring radio waves emitted from the satellites.

Conventionally, it has been extremely difficult to determine orbital elements by simply observing radio waves from orbiting satellites. Although Patent Document 1 describes a method and apparatus for determining the orbit of a satellite, the orbital element is determined from only the information on the direction and time when the radio wave from the orbiting satellite that is the subject of the present invention is measured. No method or apparatus for estimation is disclosed.
JP 02-122308 A

  As described above, conventionally, it has been extremely difficult to determine orbital elements only by observing radio waves from orbiting satellites.

  An object of the present invention is to solve the above problems and to provide an orbiting satellite orbit element estimation apparatus and method that can easily estimate an orbit element from radio waves from an orbiting satellite.

  In order to solve the above problems, an orbiting satellite orbit element estimation apparatus and method according to the present invention receives radio waves from an orbiting satellite and tracks a satellite orbit that changes from time to time by a step track tracking method. The trajectory passed by the orbiting satellite is recorded together with time information, and when the orbital element of the orbiting satellite is estimated based on the tracking measurement result, the tracking measurement result and the estimated orbital element are calculated. The trajectory element is estimated so that an error from the direction at the measurement time is minimized.

  In the orbiting satellite orbit element estimation apparatus and method according to the above configuration, in the step track tracking process, the reception level of the radio wave received by the reception antenna is measured by the reception unit, and the reception level is changed while the antenna directing direction is changed by the antenna control unit. Control to maximize. The direction of arrival of the satellite radio wave is recorded together with the measurement time, the orbital element is determined so that the error between the measurement result and the estimated orbital element calculated in the orbital element estimation process is minimized, and the result is displayed on the display unit.

  Therefore, according to the present invention, it is possible to provide an orbiting satellite orbital element estimation apparatus and method that can easily estimate an orbital element from radio waves from the orbiting satellite.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a block diagram schematically showing a configuration of an orbiting satellite orbit element estimation apparatus according to an embodiment of the present invention. This apparatus includes a receiving antenna 10, an antenna control unit 20, a receiving unit 30, a step track tracking processing unit 40, an orbital element estimation processing unit 50, and a display unit 60.

  The receiving antenna 10 is a receiving antenna that can measure radio waves from an orbiting satellite (not shown). The shape and type of the antenna are arbitrary depending on the object to be measured, the purpose of measurement, and the like, but a parabolic antenna that can receive weak radio waves from a satellite and has a sufficient aperture size is desirable.

  The antenna control unit 20 has a mechanism for tracking the satellite, and directs the antenna 10 in the direction instructed by the step track tracking processing unit 40. The antenna control unit 20 has a driving speed performance sufficient to track the orbiting satellite. Have.

  The receiving unit 30 acquires a reception level from a received signal from the receiving antenna 10 and has performances such as a frequency range and sensitivity sufficient to receive a radio wave from an orbiting satellite.

  FIG. 2 shows an overall processing flow in the above configuration. In step 11, a step track tracking process for tracking the orbiting satellite is performed. A radio wave from the satellite is received, the direction of the antenna 10 is controlled, the direction in which the satellite radio wave that is converted from moment to moment is measured, and recorded together with the measurement time. Step track tracking is a method in which the direction in which the reception level is maximized while controlling the antenna directivity direction is the direction in which satellite radio waves arrive. In step 12, the trajectory element estimation processing unit 50 performs a trajectory element estimation process. In step 13, the trajectory element estimation result is displayed.

  Next, the trajectory element estimation process that characterizes the present invention will be described with reference to the trajectory element estimation process flow shown in FIG. 3 and the conceptual diagram shown in FIG.

  First, in step 101, the trajectory element has a plurality of parameters, and designates a range for generating a uniform random number for each. First, the parameters of the trajectory elements are estimated by specifying a wide range and gradually narrowing down. Generate trajectory element parameters in the specified generation range. As shown in FIG. 4A, the orbital element parameters include an AZ angle, an EL angle, and a time when the orbiting satellite S is viewed from the measurement position.

  In step 102, an error amount between the estimated satellite direction calculated using the generated orbital element is calculated from the measured arrival direction of the satellite radio wave and the measured time information.

  Step 101 and step 102 are repeated a preset number of times.

  In step 103, the trajectory element having the smallest error amount among the error amounts calculated in step 101 and step 102 is detected. An example is shown in FIG. In FIG. 4B, the horizontal axis represents AZ and the vertical axis represents EL, and the measurement result and the estimation calculation result are sequentially compared at a predetermined time, and the trajectory element is determined so that the error is minimized.

  In step 104, the range in which uniform random numbers are generated is narrowed in the vicinity of the orbital element that has the smallest error amount, and steps 101 to 103 are repeated. Finally, the trajectory element with the smallest error amount is output as the estimation result.

  As described above, according to the orbiting satellite orbit element estimation device having the above-described configuration, the orbital element can be estimated only from the information on the direction and time when the radio wave from the orbiting satellite is measured.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

It is a block diagram which shows roughly the structure of the orbiting satellite orbit element estimation apparatus in connection with one Embodiment of this invention. It is a flowchart which shows the flow of the whole process of the apparatus shown in FIG. It is a flowchart which shows the flow of the orbital element estimation process of the apparatus shown in FIG. It is a conceptual diagram for demonstrating the trajectory element estimation process shown in FIG.

Explanation of symbols

10 ... receiving antenna,
20: Antenna control unit,
30 ... Step track processing unit,
40 ... orbital element estimation processing unit,
50: Display unit.

Claims (2)

Receiving means for receiving radio waves from the orbiting satellite;
A tracking control processing unit for tracking a satellite orbit that changes from time to time from the received signal of the receiving means by a step track tracking method and recording a trajectory of the orbiting satellite together with time information;
The orbital element of the orbiting satellite is estimated based on the tracking measurement result, and the orbital element is such that the error between the tracking measurement result and the direction at the measurement time calculated by the estimated orbital element is minimized. Orbital element estimation processing means for estimating the orbital satellite orbital element estimation device. Receiving radio waves from the orbiting satellite, tracking the satellite trajectory that changes from moment to moment from this received signal by the step track tracking method, and recording the trajectory passed by the orbiting satellite along with time information,
When estimating the orbital element of the orbiting satellite based on the measurement result of the tracking, the orbital element is set such that an error between the measurement result of the tracking and the azimuth at the measurement time calculated by the estimated orbital element is minimized. An orbiting satellite orbital element estimation method characterized by estimating.

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