{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,14]],"date-time":"2026-05-14T17:33:55Z","timestamp":1778780035630,"version":"3.51.4"},"reference-count":59,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2021,6,1]],"date-time":"2021-06-01T00:00:00Z","timestamp":1622505600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Pulse compression techniques are commonly used in linear frequency modulated (LFM) waveforms to improve the signal-to-noise ratios (SNRs) and range resolutions of pulsed radars, whose detection capabilities are affected by the sidelobes. In this study, a sidelobe reduction filter (SRF) was designed and implemented using software defined radio (SDR). An enhanced matched filter (EMF) that combines a matched filter (MF) and an SRF is proposed and was implemented. In contrast to the current commonly used approaches, the mathematical model of the SRF frequency response is extracted without depending on any iteration methods or adaptive techniques, which results in increased efficiency and computational speed for the developed model. The performance of the proposed EMF was verified through the measurement of four metrics, including the peak sidelobe ratio (PSLR), the impulse response width (IRW), the mainlobe loss ratio (MLR), and the receiver operational characteristics (ROCs) at different SNRs. The ambiguity function was then used to characterize the Doppler effect on the designed EMF. In addition, the detection of single and multiple targets using the proposed EMF was performed, and the results showed that it overcame the masking problem due to its effective reduction of the sidelobes. Hence, the practical application of the EMF matches the performance analysis. Moreover, when implementing the EMF proposed in this paper, it outperformed the common MF, especially when detecting targets moving at low speeds and having small radar cross-sections (RCS), even under severe masking conditions.<\/jats:p>","DOI":"10.3390\/s21113835","type":"journal-article","created":{"date-parts":[[2021,6,1]],"date-time":"2021-06-01T23:07:03Z","timestamp":1622588823000},"page":"3835","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Design and Implementation of an Enhanced Matched Filter for Sidelobe Reduction of Pulsed Linear Frequency Modulation Radar"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7697-6611","authenticated-orcid":false,"given":"Ahmed","family":"Azouz","sequence":"first","affiliation":[{"name":"Electrical Engineering Branch, Military Technical College, Kobry El-Kobba, Cairo 11766, Egypt"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6319-2877","authenticated-orcid":false,"given":"Ashraf","family":"Abosekeen","sequence":"additional","affiliation":[{"name":"Electrical Engineering Branch, Military Technical College, Kobry El-Kobba, Cairo 11766, Egypt"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sameh","family":"Nassar","sequence":"additional","affiliation":[{"name":"Mobile Multi-Sensor Systems Research Group, University of Calgary, Calgary, AB T2N 1N4, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8583-0366","authenticated-orcid":false,"given":"Mohamed","family":"Hanafy","sequence":"additional","affiliation":[{"name":"Electrical Engineering Branch, Military Technical College, Kobry El-Kobba, Cairo 11766, Egypt"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,6,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"825","DOI":"10.1109\/7.18654","article-title":"The early history of pulse compression radar-the history of pulse compression at Sperry Gyroscope Company","volume":"24","author":"Cooke","year":"1988","journal-title":"IEEE Trans. Aerosp. Electron. Syst."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"833","DOI":"10.1109\/7.18655","article-title":"The early history of pulse compression radar-the development of AN\/FPS-17 coded-pulse radar at Lincoln Laboratory","volume":"24","author":"Siebert","year":"1988","journal-title":"IEEE Trans. Aerosp. Electron. Syst."},{"key":"ref_3","unstructured":"Skonlik, M. (2008). Radar Handbook, McGraw\u2013Hill. [3rd ed.]."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"265","DOI":"10.1016\/j.ultras.2012.06.010","article-title":"Chirp excitation of ultrasonic guided waves","volume":"53","author":"Michaels","year":"2013","journal-title":"Ultrasonics"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"094901","DOI":"10.1063\/1.2976673","article-title":"Pulse compression approach to infrared nondestructive characterization","volume":"79","author":"Mulaveesala","year":"2008","journal-title":"Rev. Sci. Instrum."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"635","DOI":"10.1038\/nphoton.2014.111","article-title":"Truncated-correlation photothermal coherence tomography for deep subsurface analysis","volume":"8","author":"Kaiplavil","year":"2014","journal-title":"Nat. Photonics"},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Zhang, Y.X., Liu, Q.F., Hong, R.J., Pan, P.P., and Deng, Z.M. (2016). A Novel Monopulse Angle Estimation Method for Wideband LFM Radars. Sensors, 16.","DOI":"10.3390\/s16060817"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"2","DOI":"10.1109\/MAES.2016.160071","article-title":"Overview of radar waveform diversity","volume":"31","author":"Blunt","year":"2016","journal-title":"IEEE Aerosp. Electron. Syst. Mag."},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Richards, M.A., Scheer, J., Holm, W.A., and Melvin, W.L. (2010). Principles of Modern Radar, SciTech Publishing.","DOI":"10.1049\/SBRA021E"},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Seleym, A. (2016, January 19\u201321). Complementary phase coded LFM waveform for SAR. Proceedings of the 2016 Integrated Communications Navigation and Surveillance (ICNS), Herndon, VA, USA.","DOI":"10.1109\/ICNSURV.2016.7486346"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"2756","DOI":"10.1109\/TAES.2012.6237627","article-title":"Range sidelobes suppression in pulse-compression radar using Golay pairs: Some basic limitations for complex targets","volume":"48","author":"Galati","year":"2012","journal-title":"IEEE Trans. Aerosp. Electron. Syst."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"40","DOI":"10.1109\/MAES.2017.160113","article-title":"Complementary pair radar waveforms\u2013evaluating and mitigating some drawbacks","volume":"32","author":"Levanon","year":"2017","journal-title":"IEEE Aerosp. Electron. Syst. Mag."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"392","DOI":"10.1109\/TAES.2008.4517015","article-title":"Best-known autocorrelation peak sidelobe levels for binary codes of length 71 to 105","volume":"44","author":"Nunn","year":"2008","journal-title":"IEEE Trans. Aerosp. Electron. Syst."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"637","DOI":"10.1109\/TAES.1982.309276","article-title":"Linear frequency modulation derived polyphase pulse compression codes","volume":"5","author":"Lewis","year":"1982","journal-title":"IEEE Trans. Aerosp. Electron. Syst."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"996","DOI":"10.1109\/PROC.1984.12967","article-title":"A study of a class of detection waveforms having nearly ideal range-Doppler ambiguity properties","volume":"72","author":"Costas","year":"1984","journal-title":"Proc. IEEE"},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Vizitiu, I.C., Enache, F., and Popescu, F. (2014, January 22\u201324). Sidelobe reduction in pulse-compression radar using the stationary phase technique: An extended comparative study. Proceedings of the 2014 International Conference on Optimization of Electrical and Electronic Equipment (OPTIM), Bran, Romania.","DOI":"10.1109\/OPTIM.2014.6850932"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"119","DOI":"10.2528\/PIERC14010605","article-title":"Some aspects of sidelobe reduction in pulse compression radars using NLFM signal processing","volume":"47","author":"Vizitiu","year":"2014","journal-title":"Prog. Electromagn. Res."},{"key":"ref_18","unstructured":"Labitt, M. (1994). Obtaining Low Sidelobes Using Non-Linear FM Pulse Compression, Lincoln Laboratory, MIT. Technical Report."},{"key":"ref_19","unstructured":"Scholnik, D.P. (2000, January 4\u20138). Optimal filters for range-time sidelobe suppression. Proceedings of the 2000 10th European Signal Processing Conference, Tampere, Finland."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"2230","DOI":"10.1109\/TAES.2014.130362","article-title":"Polyphase-coded FM (PCFM) radar waveforms, part II: Optimization","volume":"50","author":"Blunt","year":"2014","journal-title":"IEEE Trans. Aerosp. Electron. Syst."},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Guan, C., Zhou, Z., and Zeng, X. (2019). Optimal Waveform Design Using Frequency-Modulated Pulse Trains for Active Sonar. Sensors, 19.","DOI":"10.3390\/s19194262"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"106411","DOI":"10.1016\/j.optlaseng.2020.106411","article-title":"On the application of an optimized Frequency-Phase Modulated waveform for enhanced infrared thermal wave radar imaging of composites","volume":"138","author":"Hedayatrasa","year":"2021","journal-title":"Opt. Lasers Eng."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"5637","DOI":"10.1109\/TII.2018.2834462","article-title":"Induction Infrared Thermography and Thermal-Wave-Radar Analysis for Imaging Inspection and Diagnosis of Blade Composites","volume":"14","author":"Yang","year":"2018","journal-title":"IEEE Trans. Ind. Inform."},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Levanon, N., and Mozeson, E. (2004). Radar Signals, John Wiley & Sons.","DOI":"10.1002\/0471663085"},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Poularikas, A.D. (1998). Handbook of Formulas and Tables for Signal Processing, CRC Press.","DOI":"10.1201\/9781420049701"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"1886","DOI":"10.1109\/TCSI.2018.2862868","article-title":"Pulse compression in nondestructive testing applications: Reduction of near sidelobes exploiting reactance transformation","volume":"66","author":"Burrascano","year":"2018","journal-title":"IEEE Trans. Circuits Syst. Regul. Pap."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"1745","DOI":"10.1016\/j.ultras.2014.03.007","article-title":"Coded waveforms for optimised air-coupled ultrasonic nondestructive evaluation","volume":"54","author":"Hutchins","year":"2014","journal-title":"Ultrasonics"},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Liu, M., Li, Z., and Liu, L. (2018). A Novel Sidelobe Reduction Algorithm Based on Two-Dimensional Sidelobe Correction Using D-SVA for Squint SAR Images. Sensors, 18.","DOI":"10.3390\/s18030783"},{"key":"ref_29","unstructured":"Mahafza, B.R. (2013). Radar Systems Analysis and Design Using MATLAB Third Edition, CRC Press."},{"key":"ref_30","unstructured":"Fam, A., and Sarkar, I. (2010). Mismatched Filter. (7,843,382), US Patent."},{"key":"ref_31","unstructured":"Baden, J., and Cohen, M. (1991, January 26\u201327). Optimal sidelobe suppression for biphase codes. Proceedings of the NTC\u201991-National Telesystems Conference Proceedings, Atlanta, GA, USA."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"1238","DOI":"10.1109\/TAES.2007.4383616","article-title":"Pulse Compression Sidelobe Reduction by Minimization of Lp-Norms","volume":"43","author":"Cilliers","year":"2007","journal-title":"IEEE Trans. Aerosp. Electron. Syst."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"2218","DOI":"10.1109\/TAES.2014.130361","article-title":"Polyphase-coded FM (PCFM) radar waveforms, part I: Implementation","volume":"50","author":"Blunt","year":"2014","journal-title":"IEEE Trans. Aerosp. Electron. Syst."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"1587","DOI":"10.1109\/TAES.2016.140556","article-title":"Mismatch filter design via convex optimization","volume":"52","author":"Kajenski","year":"2016","journal-title":"IEEE Trans. Aerosp. Electron. Syst."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"1087","DOI":"10.1109\/TAES.1971.310209","article-title":"Range sidelobe suppression for Barker codes","volume":"AES-7","author":"Rihaczek","year":"1971","journal-title":"IEEE Trans. Aerosp. Electron. Syst."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"673","DOI":"10.1109\/7.55562","article-title":"A new algorithm to optimize Barker code sidelobe suppression filters","volume":"26","author":"Hua","year":"1990","journal-title":"IEEE Trans. Aerosp. Electron. Syst."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"348","DOI":"10.1109\/TAES.2012.6129640","article-title":"Range sidelobe reduction filter design for binary coded pulse compression system","volume":"48","author":"Akbaripour","year":"2012","journal-title":"IEEE Trans. Aerosp. Electron. Syst."},{"key":"ref_38","doi-asserted-by":"crossref","unstructured":"Gini, F., Rangaswamy, M., and Base, H.A.F. (2008). Knowledge Based Radar Detection, Tracking, and Classification, John Wiley and Sons.","DOI":"10.1002\/9780470283158"},{"key":"ref_39","unstructured":"Gabriel, W.F. (1990, January 7\u201310). Superresolution techniques in the range domain. Proceedings of the IEEE International Conference on Radar, Arlington, VA, USA."},{"key":"ref_40","unstructured":"Gabriel, W.F. (1989, January 29\u201330). Superresolution techniques and ISAR imaging. Proceedings of the IEEE National Radar Conference, Dallas, TX, USA."},{"key":"ref_41","first-page":"66","article-title":"A recursive method for the resolution of wideband signals with substantially different intensities","volume":"23","author":"Abramovich","year":"1978","journal-title":"Radio Eng. Electron. Phys"},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"72","DOI":"10.1109\/TSP.2003.820075","article-title":"Effective CLEAN algorithms for performance-enhanced detection of binary coding radar signals","volume":"52","author":"Deng","year":"2004","journal-title":"IEEE Trans. Signal Process."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"572","DOI":"10.1109\/TAES.2006.1642573","article-title":"Adaptive pulse compression via MMSE estimation","volume":"42","author":"Blunt","year":"2006","journal-title":"IEEE Trans. Aerosp. Electron. Syst."},{"key":"ref_44","doi-asserted-by":"crossref","unstructured":"Blunt, S.D., and Higgins, T. (2007, January 17\u201320). Achieving real-time efficiency for adaptive radar pulse compression. Proceedings of the 2007 IEEE Radar Conference, Waltham, MA, USA.","DOI":"10.1109\/RADAR.2007.374201"},{"key":"ref_45","doi-asserted-by":"crossref","unstructured":"Henke, D., McCormick, P., Blunt, S.D., and Higgins, T. (2015, January 10\u201315). Practical aspects of optimal mismatch filtering and adaptive pulse compression for FM waveforms. Proceedings of the 2015 IEEE Radar Conference (RadarCon), Arlington, VA, USA.","DOI":"10.1109\/RADAR.2015.7131167"},{"key":"ref_46","doi-asserted-by":"crossref","unstructured":"Li, C.X., Guo, M.F., and Zhao, H.F. (2020). An Iterative Deconvolution-Time Reversal Method with Noise Reduction, a High Resolution and Sidelobe Suppression for Active Sonar in Shallow Water Environments. Sensors, 20.","DOI":"10.3390\/s20102844"},{"key":"ref_47","doi-asserted-by":"crossref","unstructured":"Azouz, A., Ghanem, S., Horn, A., and Elbardawiny, A. (2018, January 3\u20135). A New Sidelobe Cancellation Method for LFM Radars. Proceedings of the 11th International Conference on Electrical Engineering (ICEENG), Cairo, Egypt.","DOI":"10.21608\/iceeng.2018.30132"},{"key":"ref_48","doi-asserted-by":"crossref","unstructured":"Azouz, A., Eldemiry, A., Horn, A., and Gaafar, A. (2018, January 3\u20135). New SAR Algorithm for Sidelobe Reduction in Range direction. Proceedings of the 11th International Conference on Electrical Engineering (ICEENG), Cairo, Egypt.","DOI":"10.21608\/iceeng.2018.30138"},{"key":"ref_49","doi-asserted-by":"crossref","unstructured":"Azouz, A. (2020, January 7\u20139). Novel Sidelobe cancellation for Compound-Barker Combined with LFM or Polyphase Waveform. Proceedings of the 2020 12th International Conference on Electrical Engineering (ICEENG), Cairo, Egypt.","DOI":"10.1109\/ICEENG45378.2020.9171777"},{"key":"ref_50","doi-asserted-by":"crossref","unstructured":"Azouz, A. (2019, January 29\u201330). A Modified-Matched Filter for Square Length Polyphase Codes for One Sample per Phase Code. Proceedings of the 2019 15th International Computer Engineering Conference (ICENCO), Cairo, Egypt.","DOI":"10.1109\/ICENCO48310.2019.9027443"},{"key":"ref_51","doi-asserted-by":"crossref","unstructured":"Azouz, A. (2019, January 29\u201330). A Modified-Matched Filter for Square Length Polyphase Codes for K Sample per Phase Code. Proceedings of the 2019 15th International Computer Engineering Conference (ICENCO), Cairo, Egypt.","DOI":"10.1109\/ICENCO48310.2019.9027443"},{"key":"ref_52","doi-asserted-by":"crossref","unstructured":"Azouz, A. (2020, January 7\u20139). General Sidelobe Cancellation for All Waveform of Pulsed Radars. Proceedings of the 2020 12th International Conference on Electrical Engineering (ICEENG), Cairo, Egypt.","DOI":"10.1109\/ICEENG45378.2020.9171709"},{"key":"ref_53","doi-asserted-by":"crossref","unstructured":"Higgins, T., Blunt, S.D., and Gerlach, K. (2009, January 4\u20138). Gain-constrained adaptive pulse compression via an MVDR framework. Proceedings of the 2009 IEEE Radar Conference, Pasadena, CA, USA.","DOI":"10.1109\/RADAR.2009.4977011"},{"key":"ref_54","first-page":"3","article-title":"Digital processing of synthetic aperture radar data","volume":"1","author":"Cumming","year":"2005","journal-title":"Artech House"},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"102","DOI":"10.1109\/TAES.1982.309210","article-title":"Analysis of some modified cell-averaging CFAR processors in multiple-target situations","volume":"AES-18","author":"Weiss","year":"1982","journal-title":"IEEE Trans. Aerosp. Electron. Syst."},{"key":"ref_56","doi-asserted-by":"crossref","unstructured":"Yang, R., Li, H., Li, S., Zhang, P., Tan, L., Gao, X., and Kang, X. (2018). High-Resolution Microwave Imaging, Springer.","DOI":"10.1007\/978-981-10-7138-6"},{"key":"ref_57","doi-asserted-by":"crossref","unstructured":"Liu, G., Zhang, X., and Meng, J. (2019). A Small Ship Target Detection Method Based on Polarimetric SAR. Remote Sens., 11.","DOI":"10.3390\/rs11242938"},{"key":"ref_58","doi-asserted-by":"crossref","first-page":"97","DOI":"10.1007\/s10948-018-4928-9","article-title":"The self-biased circulator: Ferrite materials design and process considerations","volume":"32","author":"Harris","year":"2019","journal-title":"J. Supercond. Nov. Magn."},{"key":"ref_59","doi-asserted-by":"crossref","first-page":"193","DOI":"10.2528\/PIERC15041301","article-title":"Design of offset dual-reflector antennas for improving isolation level between transmitter and receiver antennas","volume":"57","author":"Kong","year":"2015","journal-title":"Prog. Electromagn. Res. C"}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/21\/11\/3835\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T06:09:53Z","timestamp":1760162993000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/21\/11\/3835"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,6,1]]},"references-count":59,"journal-issue":{"issue":"11","published-online":{"date-parts":[[2021,6]]}},"alternative-id":["s21113835"],"URL":"https:\/\/doi.org\/10.3390\/s21113835","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,6,1]]}}}