Millimeter-Wave Multi-Band Reconfigurable Differential Power Divider for 5G Communication

A differential four-way power divider for 24 to 30 GHz and a frequency reconfigurable differential four-way power divider for 24 to 30 GHz and 37 to 43.5 GHz are presented. The differential structure provides sound virtual grounds in a multiple-channel chip. Both circuits have a four-way Wilkinson power divider (WPD) configuration based on lumped elements that provide small chip sizes. The first one has a small core chip area of 0.09 mm
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, a small insertion loss of 0.93 to 1.94 dB, and the port-to-port isolation of 19.1 to 25.6 dB from 24 to 30 GHz. It has a small amplitude and phase differences at four outputs. The second one allows frequency-reconfigurable operation by switching inductances and capacitances to cover widely separated frequency bands (5G NR n257-n261 bands). In addition, switched capacitors (SCs) are inserted to resonate out the parasitic series inductances in isolation resistors at both bands of 24–30 GHz and 37–43.5 GHz. It has a core chip area of 0.168 mm
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, insertion losses of 1.65–1.89 dB at 24 to 30 GHz and 2.04–2.70 dB at 37 to 43.5 GHz, respectively. The port-to-port isolations are 23.4–37.6 dB at 24 to 30 GHz and 22.6–28.4 dB at 37 to 43.5 GHz.