Design of Antennas for Handheld DVB-H ... - Lunds tekniska högskola

5 Measurements of antenna solution
Now when some different antenna prototypes have been built it is time to find out
how good they really are. Here you can read about how the measurements were
done, how accurate the measurements are and what performance the different
antenna prototypes have.
5.1 Anechoic chamber measurement
This chapter presents measurement results of our prototypes. The purposes are to
find out the efficiency and power gain for each prototype. The measurements are
made in Perlos 3D near field chamber.
5.1.1 Test set-up
All measurements presented in this chapter are made in an anechoic chamber.
Figure 5.1 shows a schematic view of the chamber. The antenna is mounted in the
centre of the chamber and is rotated in phi direction while the probes are sliding in
theta axis. Measurements are made for every tenth degree for both phi and theta.
5.1.2 Measurements
Figure 5.1. Schematic view of Perlos anechoic chamber.
Unfortunately Perlos chamber is not adapted for measurements at frequencies
lower than 700 MHz, therefore we determine the efficiency and the power gain
from a comparison with a reference antenna. All measurements presented are
rawdata.
As reference antennas we used four dipole antennas that we built ourselves, in
figure 5.2 one of the antennas is shown. Each of them was made for a 60 MHz
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