In this paper, we consider a downlink cell-free massive multi-input multi-output (mMIMO) system, assuming few-bit analog-digital converters (ADCs) and digital-analog converters (DACs) are implemented at the access points (APs). Leveraging on the linear additive quantization noise model (AQNM), we derive a tight approximate rate expression, which provides insights into the impacts of the imperfect quantization error and channel estimation error. Thanks to the trackable result, we quantitatively compare the performance differences between the two quantization models, namely the AQNM and the Bussgang theorem. In particular, the AQNM can offer analytical tractability for few-bit quantization while the Bussgang theorem only characterizes 1-bit quantization since the multi-bit quantization under the Bussgang theorem is difficult to deal with. Simulation results show that under the same 1-bit quantization, the rate performance with the Bussgang theorem is roughly identical to the case of the AQNM.
Cell-Free Massive MIMO with Few-bit ADCs/DACs: AQNM versus Bussgang
2020-05-01
168055 byte
Conference paper
Electronic Resource
English
TITELSTORY: ADCs und DACs im Detail
British Library Online Contents | 2007
Bussgang Deconvolution for Texture Synthesis and Classification
British Library Conference Proceedings | 2003
|Digital Compensation of Bandwidth Limitations for High-Speed DACs and ADCs
British Library Online Contents | 2016
|