Millimeter-Wave Multi-Channel Backscatter Communication and Ranging with an FMCW Radar

An, Shizhong; Bu, Xiangyuan; Wymeersch, Henk; Zirath, Herbert; He, Zhongxia Simon

doi:10.3390/s22197104

Cited by 2 publications

(1 citation statement)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The reason is that random signals are required for communication to convey information; however, deterministic signals are employed for sensing. For example, frequency-modulated continuous wave signals (Frequency-modulated continuous wave signals are used in radar applications) in combination with quadrature amplitude modulation (QAM) or frequency shift keying offer high sensing abilities with relatively simple transceiver design but suffer from low spectral efficiency [ 8 , 9 , 10 ]. On the other hand, 5G’s cyclic prefix (CP)-OFDM signals provide high spectral efficiency but exhibit relatively low sensing capabilities compared to their counterparts, frequency-modulated continuous wave signals [ 3 ].…”

Section: Introductionmentioning

confidence: 99%

Joint Method of Moments (JMoM) and Successive Moment Cancellation (SMC) Multiuser Time Synchronization for ZP-OFDM-Based Waveforms Applicable to Joint Communication and Sensing

Roshandeh

Mohammadkarimi

Ardakani

2023

Sensors

View full text Add to dashboard Cite

It has been recently shown that zero padding (ZP)-orthogonal frequency-division multiplexing (OFDM) is a promising candidate for 6G wireless systems requiring joint communication and sensing. In this paper, we consider a multiuser uplink scenario where users are separated in power domain, i.e., non-orthogonal multiple access (NOMA), and use ZP-OFDM signals. The uplink transmission is grant-free and users are allowed to transmit asynchronously. In this setup, we address the problem of time synchronization by estimating the timing offset (TO) of all the users. We propose two non-data-aided (NDA) estimators, i.e., the joint method of moment (JMoM) and the successive moment cancellation (SMC), that employ the periodicity of the second order moment (SoM) of the received samples for TO estimation. Moreover, the coding assisted (CA) version of the proposed estimators, i.e., CA-JMoM and CA-SMC, are developed for the case of short observation samples. We also extend the proposed estimators to multiuser multiple-input multiple-output (MIMO) systems. The effectiveness of the proposed estimators is evaluated in terms of lock-in probability under various practical scenarios. Simulation results show that the JMoM estimator can reach the lock-in probability of one for the moderate range of Eb/N0 values. While existing NDA TO estimators in the literature either offer low lock-in probability, high computational complexity that prevents them from being employed in MIMO systems, or are designed for single-user scenarios, the proposed estimators in this paper address all of these issues.

show abstract