TY - JOUR
T1 - BER Reduction Using Partial-Elements Selection in IRS-UAV Communications With Imperfect Phase Compensation
AU - Jangsher, Sobia
AU - Al-Jarrah, Mohammad
AU - Al-Dweik, Arafat
AU - Alsusa, Emad
AU - Alouini, Mohamed-Slim
N1 - KAUST Repository Item: Exported on 2022-09-14
Acknowledgements: This work was supported by Khalifa University Competitive Internal Research Award, grant no. CIRA 2020-056.
PY - 2022/7/6
Y1 - 2022/7/6
N2 - This work considers minimizing the communications bit error rate (BER) of unmanned aerial vehicle (UAV) when assisted by intelligent reflecting surfaces (IRSs). By noting that increasing the number of IRS elements in the presence of phase errors does not necessarily improve the system’s BER, it is crucial to use only the elements that contribute to reducing such a parameter. To this end, we propose an efficient algorithm to select the elements that can improve BER. The proposed algorithm has lower complexity and comparable BER to the optimum selection process which is an NP-hard problem. The accuracy of the estimated phase is evaluated by deriving the probability distribution function (PDF) of the least-square (LS) channel estimator, and showing that the PDF can be closely approximated by the von Mises distribution at high signal-to-noise ratios (SNRs). The obtained analytical and simulation results show that using all the available reflectors can significantly deteriorate the BER, and thus, partial element selection is necessary. It is shown that, in some scenarios, using about 26% of the reflectors provides more than 10 fold BER reduction. The number of selected reflectors may drop to only 10% of the total elements. As such, the unassigned 90% of the elements can be allocated to serve other users, and the overhead associated with phase information is significantly reduced.
AB - This work considers minimizing the communications bit error rate (BER) of unmanned aerial vehicle (UAV) when assisted by intelligent reflecting surfaces (IRSs). By noting that increasing the number of IRS elements in the presence of phase errors does not necessarily improve the system’s BER, it is crucial to use only the elements that contribute to reducing such a parameter. To this end, we propose an efficient algorithm to select the elements that can improve BER. The proposed algorithm has lower complexity and comparable BER to the optimum selection process which is an NP-hard problem. The accuracy of the estimated phase is evaluated by deriving the probability distribution function (PDF) of the least-square (LS) channel estimator, and showing that the PDF can be closely approximated by the von Mises distribution at high signal-to-noise ratios (SNRs). The obtained analytical and simulation results show that using all the available reflectors can significantly deteriorate the BER, and thus, partial element selection is necessary. It is shown that, in some scenarios, using about 26% of the reflectors provides more than 10 fold BER reduction. The number of selected reflectors may drop to only 10% of the total elements. As such, the unassigned 90% of the elements can be allocated to serve other users, and the overhead associated with phase information is significantly reduced.
UR - http://hdl.handle.net/10754/678145
UR - https://ieeexplore.ieee.org/document/9816032/
U2 - 10.1109/TAES.2022.3188590
DO - 10.1109/TAES.2022.3188590
M3 - Article
SN - 2371-9877
SP - 1
EP - 11
JO - IEEE Transactions on Aerospace and Electronic Systems
JF - IEEE Transactions on Aerospace and Electronic Systems
ER -