{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T03:38:38Z","timestamp":1760240318482,"version":"build-2065373602"},"reference-count":38,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2019,5,9]],"date-time":"2019-05-09T00:00:00Z","timestamp":1557360000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the open fund project from Aerospace Science and Technology","award":["105HKTG2019102002"],"award-info":[{"award-number":["105HKTG2019102002"]}]},{"name":"the open fund project from State Key Laboratory of Geographic Information Engineering","award":["SKLGIE2017-Z-2-3"],"award-info":[{"award-number":["SKLGIE2017-Z-2-3"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper presents a method of ground target detection using reflected signals of BeiDou satellites. The phase difference information, which is the output of the phase-lock loop (PLL) in the tracking process, is an important observation in this technique. The geometric relationships between the specular point of different BeiDou satellites and the target are established. In addition, the detection and false alarm probability are also analyzed. In order to verify the reliability of the method, an experiment in the suburb area of Beijing was completed. The target was placed in the coverage area of the left-handed circular polarization (LHCP) antenna for two time periods (10\u201320 s and 40\u201355 s). By observing the phase difference in BeiDou reflected signals in the presence of a target, it was found that the changing trend was in good agreement with the target placement time periods. In the second experiment, the target moved east and west at a speed of 0.5 m\/s, and the range of motion was 6 m. During the acquisition of the BeiDou reflection signal, the target passed through the antenna 14 times. The performance of target detection with different parameters was observed by extracting in-phase (I) branch component data, phase difference information, and the carrier-to-noise ratio (CNR) of five BeiDou reflected signals. The experimental results allowed three conclusions to be drawn as follows: (1) The target detection performance of the three parameters has a certain relationship with the altitude angle and the azimuth angle of the satellite; (2) target motion direction information can be reflected in the change of the satellite I branch component data; (3) The CNR information of different satellite reflected signals varies greatly when the target moves, which is quite different from that of the first experimental target when it is stationary. Thus, the feasibility of target detection using BeiDou reflection signal was demonstrated through these two experiments.<\/jats:p>","DOI":"10.3390\/s19092163","type":"journal-article","created":{"date-parts":[[2019,5,9]],"date-time":"2019-05-09T11:22:35Z","timestamp":1557400955000},"page":"2163","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Performance Analysis of Ground Target Detection Utilizing Beidou Satellite Reflected Signals"],"prefix":"10.3390","volume":"19","author":[{"given":"Chaoqun","family":"Gao","sequence":"first","affiliation":[{"name":"School of Electronic and Information Engineering, Beihang University, Beijing 100191, China"}]},{"given":"Dongkai","family":"Yang","sequence":"additional","affiliation":[{"name":"School of Electronic and Information Engineering, Beihang University, Beijing 100191, China"}]},{"given":"Xuebao","family":"Hong","sequence":"additional","affiliation":[{"name":"School of Electronic and Information Engineering, Beihang University, Beijing 100191, China"}]},{"given":"Bo","family":"Wang","sequence":"additional","affiliation":[{"name":"School of Electronic and Information Engineering, Beihang University, Beijing 100191, China"}]},{"given":"Bo","family":"Zhang","sequence":"additional","affiliation":[{"name":"School of Electronic and Information Engineering, Beihang University, Beijing 100191, China"}]}],"member":"1968","published-online":{"date-parts":[[2019,5,9]]},"reference":[{"key":"ref_1","first-page":"71","article-title":"Land Geophysical Parameters Retrieval Using the Interference Pattern GNSS-R Technique","volume":"49","author":"Camps","year":"2010","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_2","first-page":"1","article-title":"Assessment of CYGNSS Wind Speed Retrieval Uncertainty","volume":"99","author":"Ruf","year":"2018","journal-title":"IEEE J. Sel. Top. Appl. Earth Obs. Remote Sens."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"2017","DOI":"10.3390\/rs2082017","article-title":"Towards sea ice remote sensing with space detected GPS signals: Demonstration of technical feasibility and initial consis- tency check using low resolution sea ice information","volume":"2","author":"Gleason","year":"2010","journal-title":"Remote Sens."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"8369","DOI":"10.1002\/2017GL074513","article-title":"First spaceborne phase altimetry over sea ice using TechDemoSat-1 GNSS-R signals","volume":"44","author":"Li","year":"2017","journal-title":"Geophys. Res. Lett."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"2854","DOI":"10.1109\/TGRS.2017.2785343","article-title":"Revisiting the GNSS-R Waveform Statistics and Its Impact on Altimetric Retrievals","volume":"56","author":"Li","year":"2018","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"4992","DOI":"10.1109\/TGRS.2013.2286257","article-title":"Consolidating the Precision of Interferometric GNSS-R Ocean Altimetry Using Airborne Experimental Data","volume":"52","author":"Cardellach","year":"2014","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_7","first-page":"2110","article-title":"An Algorithm for Sea-Surface Wind Field Retrieval From GNSS-R Delay-Doppler Map","volume":"11","author":"Chen","year":"2014","journal-title":"Geophys. Res. Lett."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"3924","DOI":"10.1109\/TGRS.2013.2278151","article-title":"Using DDM Asymmetry Metrics for Wind Direction Retrieval From GPS Ocean-Scattered Signals in Airborne Experiments","volume":"52","author":"Valencia","year":"2014","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_9","first-page":"2028","article-title":"Stationary L-band radiometry for seasonal measurements of soil moisture","volume":"13","author":"Zavorotny","year":"2006","journal-title":"IEEE Int. Symp. Geosci. Remote Sens."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"4730","DOI":"10.1109\/JSTARS.2016.2588467","article-title":"Sensitivity of GNSS-R Spaceborne Observations to Soil Moisture and Vegetation","volume":"9","author":"Camps","year":"2016","journal-title":"IEEE J. Sel. Top. Appl. Earth Obs. Remote Sens."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"425","DOI":"10.1109\/JSTARS.2014.2341581","article-title":"Dual Antenna Space-Based GNSS-R Ocean Surface Mapping: Oil Slick and Tropical Cyclone Sensing","volume":"8","author":"Chen","year":"2015","journal-title":"IEEE J. Sel. Top. Appl. Earth Obs. Remote Sens."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"122","DOI":"10.1016\/j.rse.2012.05.012","article-title":"Characterization of dry-snow sub-structure using GNSS reflected signals","volume":"124","author":"Cardellach","year":"2012","journal-title":"Remote Sens. Environ."},{"key":"ref_13","first-page":"4743","article-title":"First Dual-Band Multiconstellation GNSS-R Scatterometry Experiment Over Boreal Forests From a Stratospheric Balloon","volume":"10","author":"Camps","year":"2016","journal-title":"IEEE J. Sel. Top. Appl. Earth Obs. Remote Sens."},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Carreno-Luengo, H., Lowe, S., Zuffada, C., Esterhuizen, S., and Ovesigharan, S. (2017, January 23\u201328). GNSS-R from the SMAP and CyGNSS missions: Application to polarimetric scatterometry and ocean altimetry. Proceedings of the 2017 IEEE International Geoscience and Remote Sensing Symposium (IGARSS), Fort Worth, TX, USA.","DOI":"10.1109\/IGARSS.2017.8128130"},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Carreno-Luengo, H., Lowe, S., Zuffada, C., Esterhuizen, S., and Ovesigharan, S. (2017). Spaceborne GNSS-R from the SMAP mission: First assessment of polarimetric scatterometry over land and cryosphere. Remote Sens., 9.","DOI":"10.3390\/rs9040362"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"2652","DOI":"10.1109\/TGRS.2015.2504242","article-title":"First Results of a GNSS-R Experiment from a Stratospheric Balloon Over Boreal Forests","volume":"54","author":"Camps","year":"2016","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_17","first-page":"2112","article-title":"Phase Altimetry with Dual Polarization GNSS-R over Sea Ice","volume":"50","author":"Fabra","year":"2012","journal-title":"IEEE J. Sel. Top. Appl. Earth Obs. Remote Sens."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"2911","DOI":"10.3390\/s130302911","article-title":"Experimental Study on the Precise Orbit Determination of the BeiDou Navigation Satellite System","volume":"13","author":"He","year":"2013","journal-title":"Sensors"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"129","DOI":"10.1007\/s10291-014-0374-8","article-title":"Multipath analysis of code measurements for BeiDou geostationary satellites","volume":"19","author":"Wang","year":"2015","journal-title":"GPS Solut."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"4130","DOI":"10.1109\/JSTARS.2015.2446684","article-title":"Feasibility of Code-Level Altimetry Using Coastal BeiDou Reflection (BeiDou-R) Setups","volume":"8","author":"Zhang","year":"2015","journal-title":"IEEE J. Sel. Top. Appl. Earth Obs. Remote Sens."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"4720","DOI":"10.1109\/JSTARS.2016.2523126","article-title":"Initial Results of Typhoon Wind Speed Observation Using Coastal GNSS-R of BeiDou GEO Satellite","volume":"9","author":"Li","year":"2016","journal-title":"IEEE J. Sel. Top. Appl. Earth Obs. Remote Sens."},{"key":"ref_22","unstructured":"Sun, J., Jiao, W., Wu, H., and Lu, M. (2014). Typhoon Wind Speed Observation Utilizing Reflected Signals from BeiDou GEO Satellites. China Satellite Navigation Conference (CSNC) 2014 Proceedings: Volume III, Springer."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"1656","DOI":"10.1109\/LGRS.2016.2600620","article-title":"Sea-State Observation Using Reflected BeiDou GEO Signals in Frequency Domain","volume":"13","author":"Wang","year":"2016","journal-title":"IEEE Geosci. Remote Sens. Lett."},{"key":"ref_24","first-page":"257","article-title":"Bohai coastal sea ice detection using BeiDou GEO satellite reflected signals","volume":"44","author":"Zhang","year":"2018","journal-title":"J. Beijing Univ. Aeronaut. Astronaut."},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Gao, H., Yang, D., Li, W., Wang, Q., Wang, F., and Yin, C. (2016, January 10\u201315). Detection of sea ice based on BeiDou-reflected signals. Proceedings of the 2016 IEEE International Geoscience and Remote Sensing Symposium, Beijing, China.","DOI":"10.1109\/IGARSS.2016.7730271"},{"key":"ref_26","first-page":"1134","article-title":"SVRM-assisted soil moisture retrieval method using reflected signal from BeiDou GEO satellites","volume":"42","author":"Yang","year":"2016","journal-title":"J. Beijing Univ. Aeronaut. Astronaut."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"2427","DOI":"10.1007\/s11430-015-0013-7","article-title":"Soil moisture estimation based on BeiDou Bl interference signal analysis","volume":"59","author":"Yan","year":"2016","journal-title":"Sci. China Earth Sci."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"5076","DOI":"10.1109\/JSTARS.2018.2882232","article-title":"Experimental Results About Traffic Flow Detection by Using GPS Reflected Signals","volume":"11","author":"Gao","year":"2018","journal-title":"IEEE J. Sel. Top. Appl. Earth Obs. Remote Sens."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"3768","DOI":"10.3390\/s140203768","article-title":"Implementation and performance of a GPS\/INS tightly coupled assisted PLL architecture using MEMS inertial sensors","volume":"14","author":"Tawk","year":"2014","journal-title":"Sensors"},{"key":"ref_30","doi-asserted-by":"crossref","unstructured":"Stevanovic, S., and Pervan, B. (2018). A GPS Phase-Locked Loop Performance Metric Based on the Phase Discriminator Output. Sensors, 18.","DOI":"10.3390\/s18010296"},{"key":"ref_31","doi-asserted-by":"crossref","unstructured":"Hofmann-Wellenhof, B., Lichtenegger, H., and Collins, J. (2001). Global Positioning System: Theory and Practice, Springer.","DOI":"10.1007\/978-3-7091-6199-9"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"29970","DOI":"10.3390\/s151229780","article-title":"Assessment of the Contribution of BeiDou GEO, IGSO, and MEO Satellites to PPP in Asia-Pacific Region","volume":"15","author":"Zhao","year":"2015","journal-title":"Sensors"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"1509","DOI":"10.1109\/LGRS.2013.2297697","article-title":"Partial Interferometric Processing of Reflected GNSS Signals for Ocean Altimetry","volume":"11","author":"Li","year":"2014","journal-title":"IEEE Geosci. Remote Sens. Lett."},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Motte, E., and Zribi, M. (2017). Optimizing Waveform Maximum Determination for Specular Point Tracking in Airborne GNSS-R. Sensors, 17.","DOI":"10.3390\/s17081880"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"639","DOI":"10.1109\/JSTARS.2017.2775647","article-title":"A New Approach to Determine the Specular Point of Forward Reflected GNSS Signals","volume":"111","author":"Southwell","year":"2018","journal-title":"IEEE J. Sel. Top. Appl. Earth Obs. Remote Sens."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"6007","DOI":"10.1109\/TGRS.2016.2579504","article-title":"A Statistical Model and Simulator for Ocean-Reflected GNSS Signals","volume":"54","author":"Garrison","year":"2016","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"537","DOI":"10.1109\/TGRS.2013.2242332","article-title":"Effects of Near-Surface Soil Moisture on GPS SNR Data: Development of a Retrieval Algorithm for Soil Moisture","volume":"52","author":"Chew","year":"2013","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"1104","DOI":"10.1016\/j.asr.2014.11.019","article-title":"Assessment of modernized GPS L5 SNR for ground-based multipath reflectometry applications","volume":"55","author":"Tabibi","year":"2015","journal-title":"Adv. Space Res."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/19\/9\/2163\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T12:50:37Z","timestamp":1760187037000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/19\/9\/2163"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2019,5,9]]},"references-count":38,"journal-issue":{"issue":"9","published-online":{"date-parts":[[2019,5]]}},"alternative-id":["s19092163"],"URL":"https:\/\/doi.org\/10.3390\/s19092163","relation":{},"ISSN":["1424-8220"],"issn-type":[{"type":"electronic","value":"1424-8220"}],"subject":[],"published":{"date-parts":[[2019,5,9]]}}}