2018/03/07 by Muhammed Faruk Gencel, Gencel, Muhammed Faruk, Maryam Eslami Rasekh +3 · 1 citation
Computer Science · Engineering · #Advanced MIMO Systems Optimization #Cooperative Communication and Network Coding #FOS: Computer and information sciences #Information Theory (cs.IT) #Millimeter-Wave Propagation and Modeling
paper · pdf · doi:10.48550/arxiv.1803.02877
openalex publication_date 2018/03/07 · openalex created_date 2022/10/04 · openalex updated_date 2026/07/28
We propose a concept system termed distributed base station (DBS), which\nenables distributed transmit beamforming at large carrier wavelengths to\nachieve significant range extension and/or increased downlink data rate,\nproviding a low-cost infrastructure for applications such as rural broadband.\nWe consider a frequency division duplexed (FDD) system, using feedback from the\nreceiver to achieve the required phase coherence. At a given range, N\ncooperating transmitters can achieve N2-fold increase in received power\ncompared to that for a single transmitters, and feedback-based algorithms with\nnear-ideal performance have been prototyped. In this paper, however, we\nidentify and address key technical issues in translating such power gains into\nrange extension via a DBS. First, to combat the drop in per-node SNR with\nextended range, we design a feedback-based adaptation strategy that is suitably\nrobust to noise. Second, to utilize available system bandwidth, we extend\nnarrowband adaptation algorithms to wideband channels through interpolation\nover OFDM subcarriers. Third, we observe that the feedback channel may become a\nbottleneck unless sophisticated distributed reception strategies are employed,\nbut show that acceptable performance can still be obtained with standard uplink\nreception if channel time variations are slow enough. We quantify system\nperformance compactly via outage capacity analyses.\n