Dual-Band 28- and 39-GHz Phased Arrays for Multistandard 5G Applications

This article presents a 32-element 28/39-GHz dual-band phased array for fifth-generation (5G) communication systems. The array is based on separate sets of SiGe transmit/ receive (Tx/Rx) beamformer chips to realize independent dual-beamforming capabilities at orthogonal linear polarizations. The beamformer chips are integrated with an
$8 \times 4$
dual-band stacked patch antenna array on a low-cost printed circuit board (PCB) and grouped together using two different Wilkinson networks to form two separate beamforming systems. The dual-band array demonstrates a measured effective isotropic radiated power (EIRP) of 40–42 dBm at the 28- and 39-GHz bands. The array is capable of scanning ±55° in the 28-GHz band and ±40° in the 39-GHz band, both in the azimuth plane. In simultaneous dual-frequency dual-beam operation with the 28-GHz band on the V-pol. and the 39-GHz band on the H-pol., spectrum measurement shows that the array has no visible intermodulation products between the 28- and 39-GHz beams. Also, complex modulation measurements with 64-QAM waveforms show < 3% error vector magnitude (EVM) at an EIRP of up to 36-dBm EIRP for both beams radiating together and without interference with each other. This work demonstrates the first millimeter-wave (mm-wave) 5G dual-band array and paves the way toward multistandard systems.