Example measurement Sample Clauses

Example measurement. ‌ JINST 12 In the right diagrams of figure 3 the measured VEL components |Hφ |, |Hθ,hor| and |Hθ,vert| at the output of the LPDA LNA as a function of the zenith angle Θ at 55 MHz are shown. In the left drawings the respective antenna orientations are visible. The antenna response pattern reveals the following features. For the VEL component |Hφ |, the LPDA is most sensitive in the zenith direction. The pattern shows a side lobe at around 65◦. For |Hθ,hor| the most sensitive direction is the zenith while at larger zenith angles the sensitivity is strongly reduced. At the zenith the components |Hφ | and |Hθ,hor| are equal which is expected as the antenna orientations are identical. The fluctuations in |Hθ,hor| are larger than those in |Hφ | due to the larger dependencies on the octocopter rotations. When flying towards the antenna, any acceleration causes a rotation around the pitch angle (figure 2) which does not influence |Hφ |. However, for both meridional subcomponents the pitch angle already changes the transmitting antenna orientation (figure 3). Therefore, it influences both measurements. In comparison to the other components |Hθ,vert| is much smaller. Therefore, the LPDA is marginally sensitive to such a signal polarization especially at vertical incoming directions. All these results are frequency dependent. T10005