RF Electronics Chapter 5: Frequency Mixers Page 154
2022, C. J. Kikkert, James Cook University, ISBN 978-0-6486803-9-0.
Figure 5.71. Comparison of Conversion gains for the 180 Hybrid mixers.
Figure 5.71 shows the conversion loss of the DBM using the Parallel line and Marchand
Balun and compares that with the conventional transformer based DBM of figure 5.31.
Figure 5.72. Microwave DBM down-conversion spectrum.
Figure 5.73 shows a comparison of the IF spectra, when using these mixers for down-
conversion. The signals below 1 GHz are nearly the same. The transformer based DBM
does not have any unwanted signals in the 1 – 3 GHz band. These mixers can also be used
for up-conversion. Figure 5.73 shows the mixer of figure 5.68 as an up-converter. The
resulting up-conversion loss is very similar to the conversion loss as down-converters for
the 3 mixers shown in figure 5.71. Figure 5.74 shows the RF spectrum of the Marchand
DBM used as an up-converter.
RF Electronics: Design and Simulation
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