1 research outputs found
Joint AGC and Receiver Design for Large-Scale MU-MIMO Systems Using Low-Resolution Signal Processing in C-RANs
Large-scale multi-user multiple-input multiple-output (MU-MIMO) systems and
cloud radio access networks (C-RANs) are considered promising technologies for
the fifth generation (5G) of wireless networks. In these technologies, the use
of low-resolution analog-to-digital converters (ADCs) is key for energy
efficiency and for complying with constrained fronthaul links. Processing
signals with few bits implies a significant performance loss and, therefore,
techniques that can compensate for quantization distortion are fundamental. In
wireless systems, an automatic gain control (AGC) precedes the ADCs to adjust
the input signal level in order to reduce the impact of quantization. In this
work, we propose the joint optimization of the AGC, which works in the remote
radio heads (RRHs), and a low-resolution aware (LRA) linear receive filter
based on the minimum mean square error (MMSE), which works in the cloud unit
(CU), for large-scale MU-MIMO systems with coarsely quantized signals. We
develop linear and successive interference cancellation (SIC) receivers based
on the proposed joint AGC and LRA MMSE (AGC-LRA-MMSE) approach. An analysis of
the achievable sum rates along with a computational complexity study is also
carried out. Simulations show that the proposed AGC-LRA-MMSE design provides
substantial gains in bit error rates and achievable information rates over
existing techniques.Comment: 9 figures, 14 pages. arXiv admin note: text overlap with
arXiv:1912.0628