The small wavelength at millimeter wave (mmWave) allows to pack antenna arrays in a very small area enabling practical large-scale MIMO. However, wideband and high-precision analog-to-digital converters (ADCs) are very expensive and power-hungry. In this paper, we propose a mmWave MIMO communication system that employs simple one-bit ADCs at the receiver and MIMO precoding at the transmitter. One significant challenge associated with this system is efficient channel estimation based on one-bit quantized channel output. We propose a novel continuous-time channel estimator based on level-triggered sampling, a nonuniform sampling scheme that offers estimation performance similar to that of the estimator based on full-precision channel output. We also develop the transmitter precoding scheme that reduces the transmit peak-to-average power ratio (PAPR) and, at the same time, equalizes the antenna cross-talks so that receiver demodulation can be implemented simply by symbol-rate slicing. Extensive simulation results are provided to demonstrate the effectiveness of the proposed channel estimation and precoding techniques for mmWave systems.
['Ziyu Guo', 'Yasin Yilmaz', 'Xiaodong Wang']
Transmitter-Centric Channel Estimation and Low-PAPR Precoding for Millimeter-Wave MIMO Systems