A TDD Distributed MIMO Testbed Using a 1-Bit Radio-Over-Fiber Fronthaul Architecture

• DOI: 10.48550/arxiv.2403.17476
• Publication Date: 2024-03-26
• Authors: Lise Aabel; Sven Jacobsson; Mikael Coldrey; Frida Olofsson; Giuseppe Durisi; Christian Fager
• Keywords: Testbed

We present the uplink and downlink of a time-division duplex distributed multiple-input multiple-output (D-MIMO) testbed, based on 1-bit radio-over-fiber architecture, which is low-cost scalable. The proposed architecture involves central unit (CU) that equipped with digital-to-analog analog-to-digital converters, operating at 10 GS/s. CU connected to multiple single-antenna remote radio heads (RRHs) via optical fibers, over binary RF waveform transmitted. In uplink, generated RRHs by comparator, whose inputs are received signal suitably designed dither signal. downlink, bandpass sigma-delta modulation. Our measurement results show low error-vector magnitude (EVM) can be achieved in both despite sampling CU. Specifically, for point-to-point over-cable transmission between single user equipment (UE) RRH, we report, MBd using single-carrier 16QAM modulation, an EVM 3.3% 4.5% uplink. then consider 3 serving air 2 UEs, that, after over-the-air reciprocity calibration, zero-forcing precoder basis channel estimates CU, achieves 6.4% 10.9% UE 1 2, respectively. Finally, investigate ability support orthogonal frequency-division multiplexing (OFDM) waveforms, its robustness against in-band out-of-band interference.