A Dual-Band Out-of-Phase Power Divider

This letter proposes a novel out-of-phase power divider that operates at two arbitrary frequencies. Because of the use of the balanced transmission line, namely the double-sided parallel-strip line (DSPSL), the out-of-phase feature between the two output ports can be made frequency-independent. The power divider employs three lumped components (an inductor L, a capacitor C and a resistor R) in serial connection to achieve isolation between the two output ports. The design equations are derived using the odd-mode and even-mode analysis. Experimental results show that good matching, isolation and amplitude balance are simultaneously achievable for both of the two operating frequency bands.