A Hybrid Polarimetric Wide-Band Beam-former Architecture for 5G mm-Wave Communications

Beam-forming at millimeter wave frequencies (mmwave) is a key technology to fulfill the fifth generation (5G) high data rate requirements. In this paper, we describe a novel hybrid architecture for mm-wave beam-forming, which addresses the mm-wave specific propagation channel characteristics that are identified in recent measurement campaigns. This architecture leverages baseband processing both in analog and digital domain. By enabling multi-beam beam-forming and compensating the polarization mismatch, delay difference (of different beams) and optionally the Doppler shifts (depending on mobility) of the beams at the Tx, a coherent summation of the signals in different beams can be realized, allowing to maximize the signal-to-noise ratio (SNR) and reduce the Rx complexity. Simulations based on measured channels in a typical large indoor scenario have been used to sustain the effectiveness of the proposed beam-forming architecture.