A compact SiGe BiCMOS four-way differential power divider/combiner

Differential transmission lines are a fundamental building block in many modern Monolithic Microwave Integrated Circuit (MMIC) architectures. One of the crucial functions required in these devices is the ability to divide or combine the signal in the differential mode i.e. without employing Baluns on the input and output ports. This work presents a compact four-way differential power divider/combiner implemented in a SiGe BiCMOS technology. The proposed power divider/combiner has a size of only 65×65 μm2 and it occupies only two metal layers making this device well suited for highly dense MMIC such as those employed in long-range automotive radar applications operating at the frequency of 77 GHz. Simulated results show a return loss of 31.24 dB and insertion losses of 1.7 dB for all transmitting paths.