WO1998039818A1 - A method and an apparatus for calibrating a phased array antenna - Google Patents
A method and an apparatus for calibrating a phased array antenna Download PDFInfo
- Publication number
- WO1998039818A1 WO1998039818A1 PCT/SE1998/000389 SE9800389W WO9839818A1 WO 1998039818 A1 WO1998039818 A1 WO 1998039818A1 SE 9800389 W SE9800389 W SE 9800389W WO 9839818 A1 WO9839818 A1 WO 9839818A1
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- antenna
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q3/00—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system
- H01Q3/26—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system varying the relative phase or relative amplitude of energisation between two or more active radiating elements; varying the distribution of energy across a radiating aperture
- H01Q3/267—Phased-array testing or checking devices
Definitions
- the invention relates to a method of calibrating a phased array antenna as well as to an apparatus for calibrating a phased array antenna.
- the spacing between the antenna elements is such that the period of the array factor extends outside the visible re -g&i*on of + 90°.
- the object of the invention is to eliminate the problems caused by sidelobes that
- the apparatus which comprises a control unit which is adapted to calibrate the antenna at at least two different scan angles. By calibrating the antenna at at least two different scan angles, it will be possible to reach the regions that need to be sidelobe-corrected.
- Fig. 1 schematically illustrates an embodiment of a phased a ⁇ -ay antenna according to the invention
- Fig. 2 is a flow diagram of a first method according to the invention of calibrating the antenna in Fig. 1, and
- Fig. 3 is a flow diagram of a second embodiment of the method according to the invention.
- Fig. 1 schematically illustrates an embodiment of a phased a ⁇ ay antenna 1 according to the invention.
- the antenna in a manner known per se, comprises a plurality of antenna elements 2. It is to be understood that, as an alternative, the antenna may equally well be made up of a number of subarrays comprising at least two antenna elements each (not shown).
- Each antenna element 2 (or suba ⁇ ay) is separately controlled by a transmit/receive modul (TR ) 3.
- TR transmit/receive modul
- the TRMs 3 are adapted to receive control commands from a control unit 4 which is common to all TRMs 4.
- the antenna 1 is of the type in which the spacing d between the antenna elements 2 is ⁇ ⁇ /2, ⁇ being the wavelength in vacuum of the antenna 1.
- a first embodiment of a method according to the invention of calibrating a phased a ⁇ ay antenna relative to a desired antenna pattern will be described.
- the antenna may be of the type illustrated in Fig. 1 or of any other type of phased a ⁇ ay antennas. For reasons of simplicity, the method will be described in connection with the antenna 1 shown in Fig. 1.
- the method illustrated by the flow diagram in Fig. 2 comprises a number of steps 20-28.
- step 20 excitations of the antenna elements 2 in Fig. 1, co ⁇ esponding to a desired antenna pattern are set.
- step 21 the antenna 1 in Fig. 1 is set to a first desired scan angle, e.g. 0°.
- step 22 the antenna pattern produced by the antenna 1 under the control of the control unit 4 with basic settings of amplitude and phase in the TRMs 3, is determined at the scan angle set in step 21.
- step 23 it is checked whether or not the differences between the antenna pattern determined in step 22 and the desired antenna pattern are within predete ⁇ nined limits.
- step 24 the excitations of the antenna elements 2 are calculated, in a manner known per se, from the antenna pattern produced by the antenna 1.
- step 25 differences between the excitations of the antenna elements 2 calculated in step 24 and the excitations set in step 20 in correspondence to the desired antenna pattern, are calculated.
- step 26 signals co ⁇ esponding to the differences calculated in step 25, are generated to coirect the control of the antenna elements 2 to produce a corrected antenna pattern in step 22.
- step 23 This loop of steps is repeated until the answer is "Yes” in step 23, i.e. until the differences between the antenna pattern dete ⁇ nined in step 22 and the desired antenna pattern, are within predete ⁇ nined limits.
- step 27 in accordance with the invention, it is checked whether or not the antenna 1 has been calibrated at a second desired scan angle.
- step 28 the antenna 1 is set to a second scan angle, e.g. +30°, and steps 22- 26 are repeated for that second scan angle until the answer is "Yes" in step 23. It is advantageous to control the antenna elements to produce the initial antenna pattern at the second scan angle with the final TRM settings for the first scan angle.
- step 27 it is again checked whether or not the antenna 1 has been calibrated at a second desired scan angle.
- the dete ⁇ nination of the antemia pattern in step 22 can be made either through direct measurement at the location in space where the desired pattern is defined or through measurement at another location and a subsequent transformation to the location of the desired pattern, e.g. near-field to far-field transformation and vice versa.
- the near- field pattern of the antenna is measured, and the measured near-field pattern is transformed to the location of the desired antenna pattern, e.g. the far-field. Then, the near-field pattern transformed to the far-field, is compared with the desired far-field antenna pattern.
- the calculations of the excitations in step 24 can be made starting from either directly measured antenna patterns or the transformed antenna patterns.
- the near-field pattern of the anterma is measured, the measured near-field pattern is transfo ⁇ ned to the location of the desired antenna pattern, e.g. the far-field, and near-field pattern transformed to the far-field is transformed from the far-field back to the antenna elements.
- the flow diagram in Fig. 3 comprises steps 30 - 36.
- step 30 excitations of the antenna elements 2 co ⁇ esponding to the desired antenna pattern, are set in the same manner as in step 20 in Fig. 2.
- step 31 the antenna elements 2 are controlled by the control unit 4 in Fig. 1 to produce an antenna pattern with initial TRM settings of amplitude and phase at a first and a second scan angle, e.g. +30° and -30°, respectively.
- steps 32' and 32" these two antenna patterns, produced at the first and the second scan angle, respectively, are dete ⁇ nined.
- step 33 it is checked whether or not the differences between the antenna patterns determined in steps 32' and 32", respectively, and the desired antenna pattern are within predetermined limits.
- antenna elements 2 are calculated for the respective scan angle, in a manner known
- step 35 the excitation differences calculated in steps 34' and 34" are compiled in
- differences may e.g. be fo ⁇ ned.
- step 36 the differences compiled in step 35 are converted into co ⁇ ection signals
- step 31 The loop of steps 31 - 36 is then repeated for one or more coirected antenna patterns
- step 27 in Fig. 2. the calibration process continues with step 31 in Fig. 3 as
Abstract
A phased array antenna (1) having separately controllable, regularly space antenna elements (2), the spacing (d) between the antenna elements (2) being such that the period of the array factor of the antenna (1) extends outside the visible region of the antenna (1), is calibrated in that the antenna elements (2) are controlled by a control unit (4) to produce an antenna pattern corresponding to a desired antenna pattern within predetermined limits at at least two different scan angles.
Description
A METHOD AND AN APPARATUS FOR CALIBRATING A PHASED
ARRAY ANTENNA
TECHNICAL FIELD The invention relates to a method of calibrating a phased array antenna as well as to an apparatus for calibrating a phased array antenna.
BACKGROUND OF THE INVENTION
To avoid grating-lobes at large scan angles in phased array antennas having separately controllable (amplitude and phase), regularly spaced antenna elements, the spacing between the antenna elements is such that the period of the array factor extends outside the visible re -g&i*on of + 90°.
When such an anterma is calibrated with respect to sidelobes, most often the antenna pattern for a single scan angle is used as starting data. A calibration at a scan angle of 0° will result in that the sidelobes will be essentially eliminated within the visible region at this scan angle. However, there are still uncontrolled sidelobes outside the visible region which, upon scanning, will "migrate" into the antenna pattern.
SUMMARY OF THE INVENTION
The object of the invention is to eliminate the problems caused by sidelobes that
"migrate" into the antenna pattern upon scanning.
This is attained by the method according to the invention by calibrating the antenna at at least two different scan angles.
This object is also attained by the apparatus according to the invention which comprises a control unit which is adapted to calibrate the antenna at at least two different scan angles.
By calibrating the antenna at at least two different scan angles, it will be possible to reach the regions that need to be sidelobe-corrected.
BRIEF DESCRIPTION OF THE DRAWINGS The invention will be described more in detail below with reference to the appended drawings, on which
Fig. 1 schematically illustrates an embodiment of a phased aπ-ay antenna according to the invention,
Fig. 2 is a flow diagram of a first method according to the invention of calibrating the antenna in Fig. 1, and
Fig. 3 is a flow diagram of a second embodiment of the method according to the invention.
PREFERRED EMBODIMENTS Fig. 1 schematically illustrates an embodiment of a phased aπay antenna 1 according to the invention. In the embodiment shown, the antenna 1, in a manner known per se, comprises a plurality of antenna elements 2. It is to be understood that, as an alternative, the antenna may equally well be made up of a number of subarrays comprising at least two antenna elements each (not shown). Each antenna element 2 (or subaπay) is separately controlled by a transmit/receive modul (TR ) 3. The TRMs 3 are adapted to receive control commands from a control unit 4 which is common to all TRMs 4.
The antenna 1 is of the type in which the spacing d between the antenna elements 2 is < λ/2, λ being the wavelength in vacuum of the antenna 1.
As indicated above in the introductory portion, with a spacing d < λ/2 between the antenna elements 2, there will still be uncontrolled sidelobes outside the visible region when the antenna is calibrated at a single scan angle, which sidelobes will appear when the antenna is scanned.
With reference to the flow diagram in Fig. 2, a first embodiment of a method according to the invention of calibrating a phased aιτay antenna relative to a desired antenna pattern, will be described. The antenna may be of the type illustrated in Fig. 1 or of any other type of phased aιτay antennas. For reasons of simplicity, the method will be described in connection with the antenna 1 shown in Fig. 1.
To anyone skilled in the art, it should be apparent that calibrations of antennas can be caπied out in transmitting mode as well as in receiving mode of the antenna. In fact, some antennas are calibrated in both transmitting and receiving modes with different criteria.
The method illustrated by the flow diagram in Fig. 2 comprises a number of steps 20-28.
In step 20, excitations of the antenna elements 2 in Fig. 1, coιτesponding to a desired antenna pattern are set.
In step 21, the antenna 1 in Fig. 1 is set to a first desired scan angle, e.g. 0°.
In step 22, the antenna pattern produced by the antenna 1 under the control of the control unit 4 with basic settings of amplitude and phase in the TRMs 3, is determined at the scan angle set in step 21.
In step 23, it is checked whether or not the differences between the antenna pattern determined in step 22 and the desired antenna pattern are within predeteπnined limits.
If the answer is "No", in step 24, the excitations of the antenna elements 2 are calculated, in a manner known per se, from the antenna pattern produced by the antenna 1.
In step 25, differences between the excitations of the antenna elements 2 calculated in step 24 and the excitations set in step 20 in correspondence to the desired antenna pattern, are calculated.
In step 26, signals coπesponding to the differences calculated in step 25, are generated to coirect the control of the antenna elements 2 to produce a corrected antenna pattern in step 22.
This loop of steps is repeated until the answer is "Yes" in step 23, i.e. until the differences between the antenna pattern deteπnined in step 22 and the desired antenna pattern, are within predeteπnined limits.
Then, in step 27, in accordance with the invention, it is checked whether or not the antenna 1 has been calibrated at a second desired scan angle.
In the present process, the answer is "No".
Then, in step 28, the antenna 1 is set to a second scan angle, e.g. +30°, and steps 22- 26 are repeated for that second scan angle until the answer is "Yes" in step 23. It is advantageous to control the antenna elements to produce the initial antenna pattern at the second scan angle with the final TRM settings for the first scan angle.
In step 27, it is again checked whether or not the antenna 1 has been calibrated at a second desired scan angle.
Now, the answer is "Yes" and the calibration process is terminated.
In accordance with the invention, the deteπnination of the antemia pattern in step 22 can be made either through direct measurement at the location in space where the desired pattern is defined or through measurement at another location and a
subsequent transformation to the location of the desired pattern, e.g. near-field to far-field transformation and vice versa.
In a prefeired embodiment, the near- field pattern of the antenna is measured, and the measured near-field pattern is transformed to the location of the desired antenna pattern, e.g. the far-field. Then, the near-field pattern transformed to the far-field, is compared with the desired far-field antenna pattern.
Likewise, in accordance with the invention, the calculations of the excitations in step 24 can be made starting from either directly measured antenna patterns or the transformed antenna patterns.
In a prefeιτed embodiment, the near-field pattern of the anterma is measured, the measured near-field pattern is transfoπned to the location of the desired antenna pattern, e.g. the far-field, and near-field pattern transformed to the far-field is transformed from the far-field back to the antenna elements.
With reference to the flow diagram in Fig. 3, a second embodiment of the method according to the invention of calibrating a phased airay antenna, e.g. the antenna 1 in Fig. 1, relative to a desired antenna pattern, will be described.
The flow diagram in Fig. 3 comprises steps 30 - 36.
In step 30, excitations of the antenna elements 2 coπesponding to the desired antenna pattern, are set in the same manner as in step 20 in Fig. 2.
In step 31, the antenna elements 2 are controlled by the control unit 4 in Fig. 1 to produce an antenna pattern with initial TRM settings of amplitude and phase at a first and a second scan angle, e.g. +30° and -30°, respectively.
In steps 32' and 32", these two antenna patterns, produced at the first and the second scan angle, respectively, are deteπnined.
In step 33, it is checked whether or not the differences between the antenna patterns determined in steps 32' and 32", respectively, and the desired antenna pattern are within predetermined limits.
If the answer is "Yes", the calibration process is teπninated.
If the answer is "No", in steps 34' and 34", on the one hand, the excitations of the
antenna elements 2 are calculated for the respective scan angle, in a manner known
per se as above in step 24 in Fig. 2, from the antenna patterns deteπnined in steps
32' and 32", and, on the other hand, the differences between the calculated
excitations and the excitations set in step 30 in coπespondence to the desired
antenna pattern, are calculated as above in step 25 in Fig. 2. Thus, steps 24 and 25
in Fig. 2 have been combined in steps 34' and 34" in Fig. 3.
In step 35, the excitation differences calculated in steps 34' and 34" are compiled in
a predeteπnined manner. The complex and, possibly, the weighted average of the
differences may e.g. be foπned.
In step 36, the differences compiled in step 35 are converted into coπection signals
to coπect the control of the antenna elements 2 to produce a coirected antenna
pattern in step 31.
The loop of steps 31 - 36 is then repeated for one or more coirected antenna patterns
until it is detected in step 33, that the differences between the antenna patterns
determined in steps 32' and 32", respectively, and the desired antenna pattern, are
within predeteπnined limits.
As above, when the answer is "Yes" in step 33, the calibration process is
terminated.
In a third embodiment (not illustrated) of the calibration method according to the
invention, the calibration methods illustrated in Figs. 2 and 3 are combined as
described below.
When the answer is "Yes" to the question in step 23 in Fig. 2, instead of continuing
with step 27 in Fig. 2. the calibration process continues with step 31 in Fig. 3 as
indicated by the airow in Fig. 2.
Thus, in this embodiment of the calibration method according to the invention,
calibration is cairied out at three different scan angles, e.g. 0°, +30°, and -30°
Calibrating the antenna at at least two different scan angles will eliminate the risk of
uncontrolled sidelobes "migrating" into the antenna pattern when the anterma is
scanned.
Claims
1. A method of calibrating a phased aπay antenna ( 1 ) having separately controllable, regularly spaced antenna elements (2), the spacing (d) between the antenna elements (2) being such that the period of the airay factor of the antenna (1) extends outside the visible region of the antenna (1 ), characterized by controlling the antenna elements (2) to produce an antenna pattein coiresponding to a desired antenna pattein within predetermined limits at at least two different scan angles.
2. The method according to claim 1 , characterized by the steps of a) controlling the antemia elements (2) to produce an antenna pattein at a first scan angle, b) determining whether or not the differences between the antenna pattern produced in step a) and the desired antenna pattern are within said predetermined limits, c) if the differences between the antenna pattern produced in step a) and the desired antenna pattern are not within said predeteπnined limits, calculating the excitations of the antenna elements (2) from the antenna pattein produced in step a), d) calculating the differences between the excitations calculated in step c) and excitations coπesponding to the desired antenna pattein, e) supplying the differences calculated in step d) as excitation coirections to control the antenna elements (2) to produce a coirected antenna pattern, f) repeating steps a) - e) until the differences between the antenna pattein produced in step a) and the desired antenna pattein are within said predetermined limits, g) when the differences between the antenna pattern produced in step a) and the desired antemia pattein are within said predetermined limits, controlling the antenna elements (2) to produce an antenna pattern at a second scan angle, and h) repeating steps b) - f). i) terminating the calibration.
3. The method according to claim 2, characterized in that the antenna pattern at said second scan angle in step g) is produced using the excitations of the antenna elements coiresponding to the coirected antenna pattein which, within said predetermined limits, coiresponds to the desired antenna pattein.
4. The method according to claim 1. characterized by the steps of a) controlling the antenna elements (2) to produce at least two antenna patterns at different scan angles, b) deteirriining whether or not the differences between the respective antenna patterns produced in step a) and the desired antenna pattein are within said predetermined limits, c) if the differences between the respective antenna patterns produced in step a) and the desired antenna pattern are not within said predeteπnined limits, calculating the excitations of the antenna elements (2) from the respective antenna patterns produced in step a), d) calculating the difference between the excitations calculated in step c) and excitations coiresponding to the desired antenna pattern, e) compiling the differences calculated in step d) for the respective antenna pattern, f) supplying the differences compiled in step d) as excitation coπections to control the antenna elements (2) to produce respective coirected antenna patterns, g) repeating steps b) - f) until the differences between the respective antenna patterns produced in step a) and the desired antenna pattein are within said predetermined limits, h) teirninating the calibration.
5. The method according to claim 1, characterized by the steps of a) controlling the antenna elements (2) to produce an antenna pattein at a first scan angle, b) determining whether or not the differences between the antenna pattein produced in step a) and the desired antenna pattein are within said predeteπnined limits, c) if the differences between the antenna pattein produced in step a) and the desired antenna pattern are not within said predeteπnined limits, calculating the excitations of the antenna elements (2) from the antenna pattern produced in step a), d) calculating the differences between the excitations calculated in step c) and excitations coiresponding to the desired antenna pattein, e) supplying the differences calculated in step d) as excitation coirections to control the antenna elements (2) to produce a coirected antenna pattern, f) repeating steps a) - e) until the differences between the antenna pattern produced in step a) and the desired antemia pattein are within said predetermined limits, g) when the differences between the antenna pattern produced in step a) and the desired antenna pattein are within said predeteπnined limits, controlling the antenna elements (2) to produce at least two antenna patterns at scan angles different from said first scan angle, h) determining whether or not the differences between the respective antenna patterns produced in step g) and the desired antenna pattein are within said predetermined limits, i) if the differences between the respective antenna patterns produced in step g) and the desired antenna pattern are not within said predetermined limits, calculating the excitations of the antemia elements (2) from the respective antenna patterns produced in step g), j) calculating the difference between the excitations calculated in step i) and excitations coiresponding to the desired antenna pattern, k) compiling the differences calculated in step j) for the respective antenna pattern, 1) supplying the differences compiled in step k) as excitation coirections to control the antenna elements (2) to produce respective coirected antenna patterns, m) repeating steps g) - 1) until the differences between the respective antenna patterns produced in step g) and the desired antenna pattein are within said predetermined limits, n) terminating the calibration.
6. The method according to any one of claims 2 - 5. characterized in that the step of determining whether or not the differences between the antenna pattern produced and the desired antenna pattein are within said predeteπnined limits, comprises the steps of measuring the near-field pattern of the antenna, transfoπning the measured near-field pattern to the location of the desired antenna pattern, and comparing the transformed near-field pattern with the desired antenna pattein.
7. The method according to any one of claims 2 - 5, characterized in that the step of calculating the excitations of the antenna elements from the antenna pattern produced, comprises the steps of measuring the near-field pattern of the antenna, transforming the measured near-field pattein to the location of the desired antenna pattern, and transforming the π-ansfoimed near-field pattein from the location of the desired antenna pattein back to the antenna elements.
8. An apparatus for calibrating a phased airay antenna (1) having separately controllable, regularly spaced antenna elements (2), the spacing (d) between the antenna elements (d) being such that the period of the airay factor of the antenna (1) extends outside the visible region of the antenna ( 1), characterized by a control unit (4) for controlling the antenna elements (2) to produce an antenna pattern coπesponding to a desired antenna pattein within predetermined limits at at least two different scan angles.
9. The apparatus according to claim 8, characterized in that the control unit (4) is adapted to carry out the steps of a) controlling the antenna elements (2) to produce an antemia pattein at a first scan angle, b) determining whether or not the differences between the antenna pattein produced in step a) and the desired antenna pattein are within said predetermined limits, c) if the differences between the antenna pattern produced in step a) and the desired antenna pattein are not within said predeteπnined limits, calculating the excitations of the antenna elements (2) from the antenna pattern produced in step a), d) calculating the differences between the excitations calculated in step c) and excitations coiresponding to the desired antenna pattein, e) supplying the differences calculated in step d) as excitation coirections to control the antenna elements (2) to produce a coirected antenna pattein, f) repeating steps a) - e) until the differences between the antenna pattein produced in step a) and the desired antenna pattern are within said predetermined limits, g) when the differences between the antenna pattein produced in step a) and the desired antenna pattern are within said predetermined limits, conu-olling the antenna elements (2) to produce an antenna pattein at a second scan angle, and h) repeating steps b) - f), i) terminating the calibration.
10. The apparatus according to claim 9, characterized in that the control unit (4) is adapted to control the antenna elements (2) to produce the antenna pattern at said second scan angle in step g) using the excitations coiresponding to the coirected antenna pattein which, within said predeteπnined limits, coiresponds to the desired antenna pattein.
11. The apparatus according to claim 8, characterized in that the control unit (4) is adapted to cany out the steps of a) controlling the antenna elements (2) to produce at least two antenna patterns at different scan angles, b) deteimining whether or not the differences between the respective antenna patterns produced in step a) and the desired antenna pattern are within said predetermined limits, c) if the differences between the respective antenna patterns produced in step a) and the desired antenna pattern are not within said predeteπnined limits, calculating the excitations of the antenna elements (2) from the respective antenna patterns produced in step a), d) calculating the difference between the excitations calculated in step c) and excitations coiresponding to the desired antenna pattern, e) compiling the differences calculated in step d) for the respective antenna pattern, f) supplying the differences compiled in step d) as excitation coirections to control the antenna elements (2) to produce respective corrected antenna patterns, g) repeating steps b) - f) until the differences between the respective antenna patterns produced in step a) and the desired antenna pattern are within said predetermined limits, h) terminating the calibration.
12. The apparatus according to claim 8, characterized in that the control unit (4) is adapted to cany out the steps of a) controlling the antenna elements (2) to produce an antenna pattern at a first scan angle, b) determining whether or not the differences between the antenna pattern produced in step a) and the desired antenna pattern are within said predetermined limits, c) if the differences between the antenna pattein produced in step a) and the desired antenna pattein are not within said predeteπnined limits, calculating the excitations of the antenna elements (2) from the antenna pattein produced in step a), d) calculating the differences between the excitations calculated in step c) and excitations coπesponding to the desired antenna pattein, e) supplying the differences calculated in step d) as excitation coirections to control the antenna elements (2) to produce a coirected antenna pattern, f) repeating steps a) - e) until the differences between the antenna pattein produced in step a) and the desired antenna pattein are within said predeteπnined limits, g) when the differences between the antenna pattein produced in step a) and the desired antenna pattein are within said predetermined limits, controlling the antenna elements (2) to produce at least two antenna patterns at scan angles different from said first scan angle, h) deteimining whether or not the differences between the respective antenna patterns produced in step g) and the desired antenna pattein are within said predeteπnined limits, i) if the differences between the respective antenna patterns produced in step g) and the desired antenna pattern are not within said predeteπnined limits, calculating the excitations of the antenna elements (2) from the respective antenna patterns produced in step g), j) calculating the difference between the excitations calculated in step i) and excitations coiresponding to the desired antenna pattein, k) compiling the differences calculated in step j) for the respective antenna pattern, 1) supplying the differences compiled in step k) as excitation coirections to control the antenna elements (2) to produce respective coirected antenna patterns, m) repeating steps g) - 1) until the differences between the respective antenna patterns produced in step g) and the desired antenna pattern are within said predetermined limits, n) terminating the calibration.
13. The apparatus according to any of claims 9 - 12. characterized in that the control unit (4) is adapted to cany out the step of deteimining whether or not the differences between the antenna pattein produced and the desired antenna pattein are within said predeteimined limits, by measuring the near-field pattern of the antenna, transforming the measured near- field pattein to the location of the desired antenna pattern, and comparing the transfoimed near-field pattein with the desired antenna pattein.
14. The apparatus according to any of claims 9 - 12, characterized in that the control unit (4) is adapted to cairy out the step of calculating the excitations of the antenna elements from the antenna pattein produced, by measuring the near-field pattern of the antenna, transfoiniing the measured near-field pattein to the location of the desired antenna pattein, and transfoiniing the transformed near-field pattern from the location of the desired antenna pattern back to the antenna elements.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| AU66444/98A AU6644498A (en) | 1997-03-07 | 1998-03-04 | A method and an apparatus for calibrating a phased array antenna |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| SE9700826-2 | 1997-03-07 | ||
| SE9700826A SE508958C2 (en) | 1997-03-07 | 1997-03-07 | Method and apparatus for calibrating a phase controlled array antenna |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| WO1998039818A1 true WO1998039818A1 (en) | 1998-09-11 |
Family
ID=20406067
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| PCT/SE1998/000389 WO1998039818A1 (en) | 1997-03-07 | 1998-03-04 | A method and an apparatus for calibrating a phased array antenna |
Country Status (3)
| Country | Link |
|---|---|
| AU (1) | AU6644498A (en) |
| SE (1) | SE508958C2 (en) |
| WO (1) | WO1998039818A1 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1309104A1 (en) * | 2000-07-14 | 2003-05-07 | Sanyo Electric Co., Ltd. | Calibration device, adaptive array device, calibration method, program recording medium and program |
| GB2384914A (en) * | 2002-02-01 | 2003-08-06 | Roke Manor Research | Antenna array calibration device |
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| US5432523A (en) * | 1993-08-20 | 1995-07-11 | The United States Of America As Represented By The Secretary Of The Air Force | Elliptical near field test facility |
| WO1995034103A1 (en) * | 1994-06-03 | 1995-12-14 | Telefonaktiebolaget Lm Ericsson | Antenna array calibration |
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| EP0752736A1 (en) * | 1995-07-07 | 1997-01-08 | General Electric Company | A method and apparatus for remotely calibrating a phased array system used for satellite communication |
| EP0762541A2 (en) * | 1995-08-29 | 1997-03-12 | Siemens Aktiengesellschaft | Device for calibrating and testing transmit/receive moduls in an active electronically phased array antenna |
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- 1997-03-07 SE SE9700826A patent/SE508958C2/en not_active IP Right Cessation
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- 1998-03-04 WO PCT/SE1998/000389 patent/WO1998039818A1/en active Application Filing
- 1998-03-04 AU AU66444/98A patent/AU6644498A/en not_active Abandoned
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| US5229776A (en) * | 1991-12-05 | 1993-07-20 | Allied-Signal Inc. | Method for field monitoring of a phased array microwave landing system far field antenna pattern employing a near field correction technique |
| US5546090A (en) * | 1991-12-12 | 1996-08-13 | Arraycomm, Inc. | Method and apparatus for calibrating antenna arrays |
| US5477229A (en) * | 1992-10-01 | 1995-12-19 | Alcatel Espace | Active antenna near field calibration method |
| US5432523A (en) * | 1993-08-20 | 1995-07-11 | The United States Of America As Represented By The Secretary Of The Air Force | Elliptical near field test facility |
| WO1995034103A1 (en) * | 1994-06-03 | 1995-12-14 | Telefonaktiebolaget Lm Ericsson | Antenna array calibration |
| EP0752736A1 (en) * | 1995-07-07 | 1997-01-08 | General Electric Company | A method and apparatus for remotely calibrating a phased array system used for satellite communication |
| EP0762541A2 (en) * | 1995-08-29 | 1997-03-12 | Siemens Aktiengesellschaft | Device for calibrating and testing transmit/receive moduls in an active electronically phased array antenna |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1309104A1 (en) * | 2000-07-14 | 2003-05-07 | Sanyo Electric Co., Ltd. | Calibration device, adaptive array device, calibration method, program recording medium and program |
| EP1309104A4 (en) * | 2000-07-14 | 2009-12-16 | Sanyo Electric Co | Calibration device, adaptive array device, calibration method, program recording medium and program |
| GB2384914A (en) * | 2002-02-01 | 2003-08-06 | Roke Manor Research | Antenna array calibration device |
| GB2384914B (en) * | 2002-02-01 | 2004-06-23 | Roke Manor Research | Antenna calibration |
Also Published As
| Publication number | Publication date |
|---|---|
| SE9700826L (en) | 1998-09-08 |
| SE9700826D0 (en) | 1997-03-07 |
| SE508958C2 (en) | 1998-11-16 |
| AU6644498A (en) | 1998-09-22 |
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