Bridging 5G and 6G: a low-complexity dual-band mmWave down-converter mixer (28/73 GHz) for 6G

A dual-band mixer capable of receiving signals in both the 5G band (n257) and a candidate 6G band (E-band) is designed and simulated using a 0.1 µm GaAs pHEMT from the UMS PH10 PDK. The device incorporates a dual-band ratrace coupler and an active FET mixer. The dual-band rat-race coupler is specifically designed to operate at 28 GHz and 73 GHz, enabling the mixer to function across both bands. The mixer achieves a conversion gain of 2.6 dB at 28 GHz and 1.1 dB at 73 GHz. The LO leakage to the IF port is measured at less than -32 dB at 28 GHz and -38 dB at 73 GHz. Additionally, the mixer demonstrates a IP1dB of -8 dBm and an IIP3 of 1.2 dBm at 28 GHz with power consumption of 6.9 mW while at 73 GHz, it achieves a IP1dB of -3 dBm and an IIP3 of 5.4 dBm with power consumption of 12.6 mW. The performance of the mixer shows promising results in both mmWave frequency bands, making it a suitable candidate for future 6G radio architectures.