28 research outputs found
Sub-Nyquist Channel Estimation over IEEE 802.11ad Link
Nowadays, millimeter-wave communication centered at the 60 GHz radio
frequency band is increasingly the preferred technology for near-field
communication since it provides transmission bandwidth that is several GHz
wide. The IEEE 802.11ad standard has been developed for commercial wireless
local area networks in the 60 GHz transmission environment. Receivers designed
to process IEEE 802.11ad waveforms employ very high rate analog-to-digital
converters, and therefore, reducing the receiver sampling rate can be useful.
In this work, we study the problem of low-rate channel estimation over the IEEE
802.11ad 60 GHz communication link by harnessing sparsity in the channel
impulse response. In particular, we focus on single carrier modulation and
exploit the special structure of the 802.11ad waveform embedded in the channel
estimation field of its single carrier physical layer frame. We examine various
sub-Nyquist sampling methods for this problem and recover the channel using
compressed sensing techniques. Our numerical experiments show feasibility of
our procedures up to one-seventh of the Nyquist rates with minimal performance
deterioration.Comment: 5 pages, 5 figures, SampTA 2017 conferenc
Radar Imaging Based on IEEE 802.11ad Waveform
The extension to millimeter-wave (mmWave) spectrum of communication frequency
band makes it easy to implement a joint radar and communication system using
single hardware. In this paper, we propose radar imaging based on the IEEE
802.11ad waveform for a vehicular setting. The necessary parameters to be
estimated for inverse synthetic aperture radar (ISAR) imaging are sampled
version of round-trip delay, Doppler shift, and vehicular velocity. The delay
is estimated using the correlation property of Golay complementary sequences
embedded on the IEEE 802.11ad preamble. The Doppler shift is first obtained
from least square estimation using radar return signals and refined by
correcting the phase uncertainty of Doppler shift by phase rotation. The
vehicular velocity is determined from the estimated Doppler shifts and an
equation of motion. Finally, an ISAR image is formed with the acquired
parameters. Simulation results show that it is possible to obtain recognizable
ISAR image from a point scatterer model of a realistic vehicular setting.Comment: 6 pages, 6 figures, and accepted for 2020 IEEE Global Communications
Conference (GLOBECOM
Distributed Radar-aided Vehicle-to-Vehicle Communication
Establishing high-rate vehicle-to-vehicle (V2V) linkswith narrow beamwidth is challenging due to the varying networktopology. A too narrow beam may miss the intended receiver,while a too broad beam leads to SNR loss. We propose toharness the high accuracy of radar detections to establish V2V links. In particular, we develop a distributed method where eachvehicle associates local radar detections with GPS informationcommunicated by nearby vehicles. The method relies on thetransformation of relative to global coordinates, the definition ofa suitable metric, and solving an optimal assignment problem. Wedemonstrate that the proposed approach avoids time-consumingchannel estimation and provides high SNR, under the conditionthat reliable relative and absolute location information is present
Radar-assisted Predictive Beamforming for Vehicle-to-Infrastructure Links
In this paper, we propose a radar-assisted predictive beamforming design for
vehicle-to-infrastructure (V2I) communication by relying on the joint sensing
and communication functionalities at road side units (RSUs). We present a novel
extended Kalman filtering (EKF) framework to track and predict kinematic
parameters of the vehicle. By exploiting the radar functionality of the RSU we
show that the communication beam tracking overheads can be drastically reduced.
Numerical results have demonstrated that the proposed radar-assisted approach
significantly outperforms the communication-only feedback based technique in
both the angle tracking and the downlink communication.Comment: 6 pages, 3 figures, accepted by IEEE ICC 2020. arXiv admin note:
substantial text overlap with arXiv:2001.0930