Page 365 - Complete Wireless Design

Support Circuit Design

364 Chapter Eight

Figure 8.34 A reactive 50-ohm splitter/combiner for low loss.

significantly lower bandwidth (around 20 percent) than a resistive design,
since it is reactive.
50
1. L .
4.4 f
1
2. C .
445 f
3. C 2 C.
2
4. R 2 Z 100 ohms.
IN
90 degree LC power splitter (Fig. 8.35). This circuit is similar to the above split-
ter, but has a 90 degree phase difference between its two output ports. It also
possesses a 20 percent bandwidth.

1. R 50 ohms.
R
2. L .
2 f
1
3. C .
1
2 fR

1
4. C 0.5
2 2 fR
Resistive splitter/combiner (Fig. 8.36). This simple resistive splitter is extreme-
ly wideband, but has a high insertion loss (6 to 7 dB) and low isolation between
ports (same level as the insertion loss).
50
1. R .
3

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