eprintid: 708
rev_number: 7
eprint_status: archive
userid: 4
dir: disk0/00/00/07/08
datestamp: 2016-03-14 16:12:52
lastmod: 2016-03-14 16:12:52
status_changed: 2016-03-14 16:12:52
type: thesis
metadata_visibility: show
creators_name: Biniam, D.
title: Quantized pulse splitting with optimized time-steps for secure communication in time-modulated linear arrays

ispublished: pub
subjects: MEA
full_text_status: public
keywords: Evolutionary Optimization, Array Synthesis, Time Modulated Arrays.
abstract: In the last years, time-modulated arrays (TMAs) have gained a growing interest since they overcome some classical drawbacks of the amplitude-weight control by arbitrarily shaping the radiated pattern by means of the modulation of the static excitations with a set of radiofrequency (RF) switches. Nevertheless, two main problems have limited the consideration of this type of array in the past: the necessity to use reliable RF switches operating at high frequency, and the generation of unwanted harmonics, the so called sideband radiation (SR), which represent a loss in term of radiated power. The new generation of RF switches thanks to the recent advance in nano-technologies are able to satisfy the operative requirements; moreover, the use of global optimization algorithms have shown that the problem of the sideband radiation can be properly handled.
In the recent years, time-modulated arrays have been studied by a new perspective in which part of the sideband radiation is exploited for useful purposes. In this framework, this project is aimed to propose a novel synthesis technique for security applications based on a customized version of the genetic algorithms. More in detail, the modified-GA developed in literature will be exploited to determine suitable pulse sequences (with quantized/splitted on-time) to keep fixed the instantaneous directivity during the modulation period, in order to nullify the sideband radiation (SR) along the direction of the desired signal and to exploit the SR to encrypt the signal radiated in the sidelobe region.

date: 2015-09-25
date_type: completed
institution: University of Trento
department: ELEDIA Research Center @ DISI
thesis_type: masters
referencetext: [1]	P. Rocca, L. Poli, G. Oliveri, and A. Massa, "A multi-stage approach for the synthesis of sub-arrayed time modulated linear arrays," IEEE Trans. Antennas Propag., vol. 59, no. 9, pp. 3246-3254, Sep. 2011.
[2]	L. Poli, P. Rocca, G. Oliveri, and A. Massa, "Harmonic beamforming in time-modulated linear arrays," IEEE Trans. Antennas Propag., vol. 59, no. 7, pp. 2538-2545, Jul. 2011.
[3]	P. Rocca, L. Poli, G. Oliveri, and A. Massa, "Adaptive nulling in time-varying scenarios through time-modulated linear arrays," IEEE Antennas Wireless Propag. Lett., vol. 11, pp. 101-104, 2012.
[4]	P. Rocca, L. Poli, and A. Massa, "Instantaneous directivity optimization in time-modulated array receivers," IET Microwaves, Antennas & Propagation, vol. 6, no. 14, pp. 1590-1597, Nov. 2012.
[5]	L. Poli, P. Rocca, and A. Massa, "Sideband radiation reduction exploiting pattern multiplication in directive time-modulated linear arrays," IET Microwaves, Antennas & Propagation, vol. 6, no. 2, pp. 214-222, 2012.
[6]	L. Poli, P. Rocca, G. Oliveri, and A. Massa, "Adaptive nulling in time-modulated linear arrays with minimum power losses," IET Microwaves, Antennas & Propagation, vol. 5, no. 2, pp. 157-166, 2011.
[7]	L. Poli, P. Rocca, L. Manica, and A. Massa, "Time modulated planar arrays - Analysis and optimization of the sideband radiations," IET Microwaves, Antennas & Propagation, vol. 4, no. 9, pp. 1165-1171, 2010.
[8]	L. Poli, P. Rocca, L. Manica, and A. Massa, "Pattern synthesis in time-modulated linear arrays through pulse shifting," IET Microwaves, Antennas & Propagation, vol. 4, no. 9, pp. 1157-1164, 2010.
[9]	P. Rocca, L. Poli, G. Oliveri, and A. Massa, "Synthesis of time-modulated planar arrays with controlled harmonic radiations," Journal of Electromagnetic Waves and Applications, vol. 24, no. 5/6, pp. 827-838, 2010.
[10]	L. Manica, P. Rocca, L. Poli, and A. Massa, "Almost time-independent performance in time-modulated linear arrays," IEEE Antennas Wireless Propag. Lett., vol. 8, pp. 843-846, 2009.
[11]	P. Rocca, L. Manica, L. Poli, and A. Massa, "Synthesis of compromise sum-difference arrays through time-modulation," IET Radar, Sonar & Navigation, vol. 3, no. 6, pp. 630-637, 2009.
[12]	L. Poli, P. Rocca, G. Oliveri, and A. Massa, "Failure correction in time-modulated linear arrays," IET Radar, Sonar & Navigation, vol. 8, no. 3, pp. 195-201, 2014. 
[13]	P. Rocca, G. Oliveri, and A. Massa, "Differential Evolution as applied to electromagnetics," IEEE Antennas Propag. Mag., vol. 53, no. 1,  pp. 38-49, Feb. 2011.

citation:   Biniam, D.  (2015) Quantized pulse splitting with optimized time-steps for secure communication in time-modulated linear arrays.  Masters thesis, University of Trento.   
document_url: http://www.eledia.org/students-reports/708/1/Abstract.A606.pdf