TEST APPARATUS AND A METHOD OF TESTING OF AN ANTENNA

1 . A measurement apparatus for the measurement of a test antenna comprising:

a movable stand for supporting the test antenna,

a feed antenna having a plurality of radiating elements, wherein the movable stand is located at a predefined distance (d) from the feed antenna; and

an antenna feed system having a plurality of adjustment components for adjusting the phase and amplitude of a wave front from the plurality of radiating elements, such that at the distance (d) the wave front is substantially planar.

2 . The measurement apparatus of claim 1 , wherein the movable stand is rotatable around at least one axis.

3 . The measurement apparatus of claim 2 , wherein the at least one axis is one of a vertical axis or a horizontal axis.

4 . The measurement apparatus of claim 1 , wherein the antenna feed system has at least one of a plurality of phase element or delay elements connected to the radiating elements, for adjusting the phase of the wave front from the plurality of radiating elements.

5 . The measurement apparatus of claim 4 , wherein a delay distribution set by the plurality of phase element or delay elements is adjusted such that there is substantially no delay at least in a center portion of the feed antenna.

6 . The measurement apparatus of claim 1 , wherein the antenna feed system has a plurality of attenuators or gain elements connected to the radiating elements, for adjusting the amplitude of the wave front from the plurality of radiating elements.

7 . The measurement apparatus of claim 6 , wherein a power distribution set by the plurality of attenuators or gain elements is adjusted such that a power is substantially constant at least in a center portion of the feed antenna.

8 . The measurement apparatus of claim 1 , wherein the feed antenna comprises between 15 and 30 radiating elements.

9 . The measurement apparatus of claim 1 , whereby ones of the plurality of radiating elements comprises at least a pair of radiating elements for producing two orthogonal polarisation components.

10 . The measurement apparatus of claim 1 , whereby the plurality of radiating elements is arranged in a linear array.

11 . A method for the testing of a test antenna in a measurement apparatus comprising:

placing the test antenna at a movable stand of the measurement apparatus;

adjusting at least one of a phase, delay and amplitude of a plurality of radiating elements forming a feed antenna, to produce a substantially planar wave front at the movable stand, using a plurality of adjustment components for adjusting said at least one of a phase, delay and amplitude;

emitting a test signal by a feed antenna and receiving the test signal by the test antenna, to derive a reception pattern of the test antenna.

12 . A method for the testing of a test antenna in a measurement apparatus comprising:

placing the test antenna at a movable stand of the measurement apparatus;

adjusting at least one of phase, delay and amplitude of a wave front from a feed antenna comprising a plurality of radiating elements, to detect a substantially planar wave front at the movable stand, using a plurality of adjustment components for adjusting at least one of phase or delay;

emitting a test signal by the test antenna and receiving the test signal at the feed antenna to derive a radiation pattern of the test antenna.

13 . The method of claim 12 , wherein the test signal is generated with at least two orthogonal polarisations.

14 . The method of claim 12 , further comprising rotating the antenna about a horizontal axis and/or about a vertical axis.

15 . The method of claim 12 , further comprising setting a same first one of at least one of phase, delay and amplitude for a first group of radiating elements and a same second one of at least one of phase, delay and amplitude for a second group of radiating elements.

16 . Use of the measurement apparatus according to any claim 1 for testing an active antenna.