Low Power and Reduced Hardware UWB Beamformers for Future 5G Communications

Abstract

We present a novel hybrid beamforming architecture for high speed 5G technologies. The architecture combines several new concepts to achieve significant hardware and cost reduction for large antenna arrays. Specifically, we employ an on-site code division multiplexing scheme to group several antenna elements into a single analog-to-digital converter (ADC). This approach significantly reduces analog hardware and power requirements by a factor of 8 to 32. Additionally, we employ a novel analog frequency independent beamforming scheme to eliminate phase shifters altogether and allow for coherent combining at the analog front-end. This approach avoids traditional phase-shifter-based approaches typically associated with bulky and inefficient components. Preliminary analysis shows that for an array of 800 elements, as much as 97% reduction in cost and power is achieved using the hybrid beamformer as compared to conventional beamformer systems.

Cross-Mixing Hybrid Beamformer for Wideband Apertures

“…2. Compared to [17], [27], each element cross-mixes with the opposite element via a separate mixer to avoid information loss. Also, our proposed design removes phase-locked loops [28] to significantly reduce hardware requirements and improve stability.…”

“…As such, this approach is limited to analog beamforming topologies. Conversely, cross-mixing elements preserves the phase delays between sub-arrays, and hence can be used with hybrid beamforming configurations [17].…”