SATELLITE SIGNAL RECEIVING APPARATUS AND ANTENNA PATTERN ADJUSTING METHOD THEREOF
20170315239 · 2017-11-02
Inventors
Cpc classification
G01S19/23
PHYSICS
H01Q3/44
ELECTRICITY
International classification
Abstract
A satellite signal receiving apparatus and an antenna pattern adjusting method thereof are provided. A coupling relationship between a main antenna and a plurality of pattern adjustment antennas is adjusted to thereby adjust an angle of the antenna pattern so that the average intensity of satellite signals attributed to target satellites and received by an antenna array is higher than a first preset intensity.
Claims
1. A satellite signal receiving apparatus, comprising: an antenna array for receiving satellite signals from a plurality of satellites, the antenna array comprising: a main antenna for radiating an antenna pattern; and at least a pattern adjustment antenna for being coupled with the antenna pattern to adjust an angle of the antenna pattern; and a control unit coupled to the at least a pattern adjustment antenna to calculate an average intensity of satellite signals of a plurality of target satellites, determine whether the average intensity is lower than a first preset intensity, and adjust a coupling relationship between the main antenna and the at least a pattern adjustment antenna if the average intensity is lower than the first preset intensity, so as to adjust the angle of the antenna pattern so that the average intensity of satellite signals attributed to the target satellites and received by the antenna array is higher than the first preset intensity.
2. The satellite signal receiving apparatus of claim 1, wherein the control unit selects from the satellites a plurality of candidate satellites having satellite signal intensity higher than a threshold intensity and calculates an average angle of elevation of the candidate satellites.
3. The satellite signal receiving apparatus of claim 2, wherein the control unit calculates the average intensity of satellite signals of the plurality of satellites and adds the calculated average intensity of satellite signals of the satellites to a second preset intensity to obtain the threshold intensity.
4. The satellite signal receiving apparatus of claim 2, wherein the control unit determines whether the average angle of elevation is smaller than a threshold angle and, if the average angle of elevation is not smaller than the threshold angle, does not adjust the angle of the antenna pattern.
5. The satellite signal receiving apparatus of claim 4, wherein the threshold angle is 60 degrees.
6. The satellite signal receiving apparatus of claim 4, wherein, if the average angle of elevation is smaller than the threshold angle, the control unit selects one of the plurality of candidate satellites, with the selected candidate satellite ranking N.sup.th by satellite signal intensity so that the satellite signal intensity of the selected candidate satellite is regarded as a standard intensity, and the control unit determines whether the standard intensity is higher than the threshold intensity so that, if the standard intensity is higher than the threshold intensity, the control unit selects some of the plurality of candidate satellites and regards the selected candidate satellites as the target satellites, with the selected candidate satellites ranking first through N.sup.th by satellite signal intensity, respectively, wherein N is a positive integer.
7. The satellite signal receiving apparatus of claim 1, wherein, if the average intensity is not lower than the first preset intensity, the control unit stops adjusting the coupling relationship between the main antenna and the at least a pattern adjustment antenna and, after a predetermined period of time has passed, keeps calculating the average intensity of satellite signals of the satellites.
8. The satellite signal receiving apparatus of claim 1, wherein the control unit determines whether the average intensity corresponding to each adjusted antenna pattern is lower than the first preset intensity, stops adjusting the coupling relationship between the main antenna and the at least a pattern adjustment antenna if the average intensity corresponding to each adjusted antenna pattern is lower than the first preset intensity, and keeps calculating the average intensity of satellite signals of the satellites after a predetermined period of time has passed.
9. The satellite signal receiving apparatus of claim 1, further comprising a plurality of switches coupled between the at least a pattern adjustment antenna and a ground, respectively, so that the control unit controls ON states of the switches to adjust the coupling relationship between the main antenna and the at least a pattern adjustment antenna.
10. An antenna pattern adjusting method, comprising the steps of: calculating an average intensity of satellite signals of a plurality of target satellites; determining whether the average intensity is lower than a first preset intensity; and adjusting a coupling relationship between the main antenna and the at least a pattern adjustment antenna if the average intensity is lower than the first preset intensity, to thereby adjust an angle of the antenna pattern so that the average intensity of the satellite signals attributed to the target satellites and received by the antenna array is higher than the first preset intensity.
11. The antenna pattern adjusting method of claim 10, further comprising the steps of: selecting a plurality of candidate satellites having satellite signal intensity higher than a threshold intensity from a plurality of satellites; and calculating an average angle of elevation of the plurality of candidate satellites relative to a pattern of the antenna array.
12. The antenna pattern adjusting method of claim 11, further comprising the steps of: calculating the average intensity of satellite signals of the satellites; and adding the calculated average intensity of satellite signals of the plurality of satellites to a second preset intensity to obtain the threshold intensity.
13. The antenna pattern adjusting method of claim 11, further comprising the steps of: determining whether the average angle of elevation is smaller than a threshold angle; and not adjusting the angle of the antenna pattern if the average angle of elevation is not smaller than the threshold angle.
14. The antenna pattern adjusting method of claim 13, wherein the threshold angle is 60 degrees.
15. The antenna pattern adjusting method of claim 13, further comprising the steps of: selecting one of the plurality of candidate satellites if the average angle of elevation is smaller than the threshold angle, wherein the selected candidate satellite ranks N.sup.th by satellite signal intensity so that the satellite signal intensity of the selected candidate satellite is regarded as a standard intensity; and determining whether the standard intensity is higher than the threshold intensity and selecting some of the candidate satellites and regarding the selected candidate satellites as the target satellites, wherein the selected candidate satellites rank first through N.sup.th by satellite signal intensity, respectively, if the standard intensity is higher than the threshold intensity, wherein N is a positive integer.
16. The antenna pattern adjusting method of claim 10, further comprising the steps of: stopping the adjustment of the coupling relationship between the main antenna and the at least a pattern adjustment antenna if the average intensity is not lower than the first preset intensity; determining whether a predetermined period of time has passed; and calculating the average intensity of satellite signals of the satellites continuously if a predetermined period of time has passed.
17. The antenna pattern adjusting method of claim 10, further comprising the steps of: determining whether the average intensity corresponding to each adjusted antenna pattern is lower than the first preset intensity; stopping the adjustment of the coupling relationship between the main antenna and the at least a pattern adjustment antenna if the average intensity corresponding to each adjusted antenna pattern is lower than the first preset intensity; determining whether a predetermined period of time has passed; and calculating the average intensity of satellite signals of the satellites continuously if a predetermined period of time has passed.
18. The antenna pattern adjusting method of claim 10, wherein the step of adjusting the coupling relationship between the main antenna and the at least a pattern adjustment antenna entails controlling the coupling relationship between the at least a pattern adjustment antenna and a ground.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0025]
[0026]
[0027]
[0028]
[0029]
[0030]
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0031]
[0032] The embodiment depicted by
[0033] The main antenna 202 and the pattern adjustment antennas 204-1, 204-2, 204-3, 204-4 are described in this embodiment for exemplary sake only. Therefore, the implementation of the main antenna 202 and the pattern adjustment antennas 204-1, 204-2, 204-3, 204-4 is not restricted to this embodiment.
[0034] In addition, the target satellites are selected in a manner described below. The control unit 106 compares the intensity of satellite signals of satellites with a threshold intensity and then selects from the satellites a plurality of candidate satellites having satellite signal intensity higher than the threshold intensity. The threshold intensity is the sum of the average intensity attributed to the satellite signals of all the satellites and calculated by the control unit 106 and a second preset intensity, wherein the second preset intensity is, for example, 0.5 dB, but the present invention is not limited thereto, nor is the way of configuring the threshold intensity limited by the present invention. Furthermore, the control unit 106 calculates the average azimuth angle and the average angle of elevation of the candidate satellites. The average azimuth angle and the average angle of elevation are for use in estimating the adjusted angle of the antenna pattern. The average angle of elevation is also for use in determining whether to adjust the pattern of the antenna array. For instance, the control unit 106 determines whether the average angle of elevation is smaller than a threshold angle, so as to not adjust the angle of the antenna pattern if the average angle of elevation is not smaller than the threshold angle, or adjust the angle of the antenna pattern if the average angle of elevation is smaller than the threshold angle.
[0035]
[0036]
TABLE-US-00001 TABLE 1 satellite satellite angle of azimuth signal ID elevation angle intensity Number (degree) (degree) (dB) satellite 1 18 50 180 32 satellite 2 193 49 210 36 satellite 3 42 65 340 39 satellite 4 10 50 100 28 satellite 5 24 50 300 35 satellite 6 12 80 335 44 satellite 7 25 65 220 40 satellite 8 21 25 40 30 satellite 9 14 85 280 37 satellite 10 20 50 100 38 satellite 11 15 60 10 41 satellite 12 22 10 282 29
[0037] The angle of elevation is observed by an user (located at the center) facing the satellite. The azimuth angle is calculated with reference to the North. For example, a satellite at the North has an azimuth angle of 0 degree. The control unit 106 compares the intensity of satellite signals of satellites with a threshold intensity (such as 36 dB, but the present invention is not limited thereto) and then selects from satellites 1˜12 a plurality of candidate satellites, such as satellites 3, 6, 7, 9, 10, 11, having satellite signal intensity higher than the threshold intensity. The control unit 106 calculates the average azimuth angle and the average angle of elevation of the candidate satellites (satellites 3, 6, 7, 9, 10, 11) and determines whether to adjust the pattern of the antenna array.
[0038] The angle of the antenna pattern is adjusted in a manner described below. The control unit 106 selects one of the candidate satellites, wherein the selected candidate satellite ranks N.sup.th by satellite signal intensity so that the satellite signal intensity of the selected candidate satellite is regarded as the standard intensity, where N is a positive integer. The control unit 106 determines whether the standard intensity is higher than the threshold intensity. If the control unit 106 determines that the standard intensity is higher than the threshold intensity, the control unit 106 selects some of the candidate satellites and regarding the selected candidate satellites as the target satellites, wherein the selected candidate satellites rank first through N.sup.th by satellite signal intensity, respectively (i.e., selecting the top N satellites with the highest satellite signal intensity and regarding them as target satellites.) For example, referring to
[0039] If the control unit 106 is already well informed of the antenna pattern angle corresponding to the coupling relationship between the main antenna and the pattern adjustment antenna, the control unit 106 will adjust the coupling relationship between the main antenna and the pattern adjustment antenna according to the average azimuth angle and the average angle of elevation which are already calculated, and in consequence the pattern of the antenna array will be adjusted to an angle corresponding to the average azimuth angle and the average angle of elevation. If the control unit 106 does not record the antenna pattern angle corresponding to the coupling relationship between the main antenna and the pattern adjustment antenna, the control unit 106 enables the coupling relationship between the main antenna and the pattern adjustment antenna to switch from one to one in turn so as to find the most appropriate antenna pattern angle and thereby attain the satisfactory satellite signal intensity. For example, in the embodiment depicted by
[0040] If the average intensity of the satellite signals of target satellites is not lower than the first preset intensity, it means that the current angle of the antenna pattern of the antenna array does not require any adjustment so that it is advisable to stop adjusting the coupling relationship between the main antenna and the pattern adjustment antenna, calculate the average intensity of the satellite signals of the satellites anew after a predetermined period of time has passed, and calculate the threshold intensity, so as to keep determining whether to adjust the angle of the antenna pattern, wherein the predetermined period of time is, for example, 300 seconds, but the present invention is not limited thereto. Furthermore, the control unit 106 determines whether the average intensity corresponding to each adjusted antenna pattern is lower than the first preset intensity. If the average intensity corresponding to each adjusted antenna pattern is lower than the first preset intensity, the control unit 106 will stop adjusting the coupling relationship between the main antenna and the pattern adjustment antenna, keep calculating the average intensity of the satellite signals of satellites after a predetermined period of time has passed, calculate the threshold intensity anew, and select new candidate satellites and target satellites, so as to adjust the angle of the antenna pattern. Hence, if it is impossible to adjust and attain the antenna pattern angle corresponding to the target satellites, the control unit 106 will be prevented from adjusting the angle of the antenna pattern continuously and thus incurring calculation-related costs. Therefore, instances of unnecessary adjustment-related attempts can be minimized by adjusting the angle of the antenna pattern only after the satellites have spent a predetermined period of time moving to different relative positions.
[0041]
[0042] For example, in the embodiment depicted by
[0043]
[0044] In this embodiment, upon determination that the average intensity of the satellite signals of target satellites is not lower than the first preset intensity or upon determination that the average intensity of the satellite signals of target satellites, which each adjusted antenna pattern corresponds to, is lower than the first preset intensity, the adjustment of the coupling relationship between the main antenna and the pattern adjustment antenna stops, and the process flow of the antenna pattern adjusting method goes to step S506-10 to determine whether a predetermined period of time has passed. In this embodiment, if a predetermined period of time has passed, the process flow of the antenna pattern adjusting method will go back to step S602 to calculate the threshold intensity anew, select new target satellites, and adjust the angle of the antenna pattern accordingly. Hence, the control unit 106 is prevented from adjusting the angle of the antenna pattern continuously and thus incurring calculation-related costs. Therefore, instances of unnecessary adjustment-related attempts can be minimized by adjusting the angle of the antenna pattern only after the satellites have spent a predetermined period of time moving to different relative positions. The predetermined period of time is, for example, 300 seconds, but the present invention is not limited thereto.
[0045] In conclusion, according to embodiments of the present invention, a coupling relationship between a main antenna and a plurality of pattern adjustment antennas is adjusted to thereby adjust the angle of an antenna pattern so that the average intensity of satellite signals attributed to target satellites and received by an antenna array is higher than a first preset intensity, so as to effectively ensure the signal reception quality of an antenna for use with a satellite signal receiving apparatus.
[0046] Although the present invention is disclosed above by embodiments, the embodiments are not restrictive of the present invention. Any persons skilled in the art can make some changes and modifications to the embodiments without departing from the spirit and scope of the present invention. Accordingly, the legal protection for the present invention should be defined by the appended claims.