Near-field focusing using phased arrays with dynamic polarization control

Phased arrays in near-field communication allow the transmitter to focus wireless signals in a small region around the receiver. Proper focusing is achieved by carefully tuning the phase shifts and the polarization of the signals transmitted from the phased array. In this paper, we study the impact of polarization on near-field focusing and...

InFocus: A spatial coding technique to mitigate misfocus in near-field LoS beamforming

Phased arrays, commonly used in IEEE 802.11ad and 5G radios, are capable of focusing radio frequency signals in a specific direction or a spatial region. Beamforming achieves such directional or spatial concentration of signals and enables phased array-based radios to achieve high data rates. Designing beams for millimeter wave and terahertz...

Structured Sensing Matrix Design for In-sector Compressed mmWave Channel Estimation

Fast millimeter wave (mmWave) channel estimation techniques based on compressed sensing (CS) suffer from low signal-to-noise ratio (SNR) in the channel measurements, due to the use of wide beams. To address this problem, we develop an in-sector CS-based mmWave channel estimation technique that focuses energy on a sector in the angle domain....

Physical Layer Defense against Eavesdropping Attacks on Low-Resolution Phased Arrays

Eavesdropping attacks are a severe threat to millimeter-wave (mmWave) networks that use low-resolution phased arrays. Although directional beamforming in mmWave phased arrays provides natural defense against eavesdropping, the use of low-resolution phase shifters induces energy leakage into unintended directions. This energy leakage can be...

Adaptive and Fast Combined Waveform-Beamforming Design for MMWave Automotive Joint Communication-Radar

Millimeter-wave (mmWave) joint communication-radar (JCR) will enable high data rate communication and high-resolution radar sensing for applications such as autonomous driving. Prior JCR systems that are based on the mmWave communications hardware, however, suffer from a limited angular field-of-view and low estimation accuracy for radars due...

Learning-aided joint time-frequency channel estimation for 5G new radio

In this paper, we propose a learning-aided signal processing solution for channel estimation in 5G new radio (NR). Channel estimation is an important algorithm for baseband modem design. In 5G NR, estimating the channel is challenging due to two reasons. First, the pilot signals are transmitted over a small fraction of the available time...