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

4.3 Folded dipole antenna
Figure 4.2. Dipole antenna.
The first antenna type that was realized was the folded dipole antenna, shown in
figure 4.2. This type of antenna was chosen because it is simple to build and is
primarily used in the same frequency bands as DVB-T is transmitted. With 600
MHz as centre frequency it can be decided that the length of the dipole antenna
should be 235 mm. The antenna impedance should be 50 Ω, to transform the
antenna impedance to this a balun was constructed by a coaxial cable. With 600
MHz as centre frequency and a coaxial cable, with known material parameter
(α=0.66), the balun should be 165 mm. For equations see figure 4.3. The coaxial
cable was connected with the SMA outlet as shown in figure 4.3.
Figure 4.3. Dipole antenna dimensions.
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