{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,19]],"date-time":"2026-02-19T06:22:21Z","timestamp":1771482141256,"version":"3.50.1"},"reference-count":35,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2022,1,26]],"date-time":"2022-01-26T00:00:00Z","timestamp":1643155200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Natural Science Foundation of China (NSFC) Project","award":["12073012"],"award-info":[{"award-number":["12073012"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>A multi-frequency Global Navigation Satellite System (GNSS) provides greater opportunities for positioning and navigation applications, particularly the BeiDou Global Navigation Satellite System (BDS-3) satellites. However, multi-frequency signals import more pseudorange channels, which introduce more multi-channel Differential Code Biases (DCBs). The satellite and receiver DCBs from the new BDS-3 signals are not clear. In this study, 9 DCB types of the new BDS-3 signals from 30-days Multi-GNSS Experiment (MGEX) observations are estimated and investigated. Compared with the DCB values provided by the Chinese Academy of Science (CAS) products, the mean bias and root mean squares (RMS) error of new BDS-3 satellite DCBs are within \u00b10.20 and 0.30 ns, respectively. The satellite DCBs are mostly within \u00b10.40 ns with respect to the product of the Deutsches Zentrum f\u00fcr Luft- und Raumfahrt (DLR). The four sets of constructed closure errors and their mean values are within \u00b10.30 ns and \u00b10.15 ns, respectively. The mean standard deviation (STD) of the estimated satellite DCBs is less than 0.10 ns. In particular, our estimated satellite DCBs are more stable than DCB products provided by CAS and DLR. Unlike satellite DCBs, the receiver DCBs have poor compliance and show an obvious relationship with the geographic latitude when compared to the CAS products. The STDs of our estimated receiver DCBs are less than 1.00 ns. According to different types of receiver DCBs, the distribution of STDs indicates that the coefficient of the ionospheric correction has an influence on the stability of the receiver DCBs under the ionosphere with the same accuracy level. In addition, the type of receiver shows no regular effects on the stability of receiver DCBs.<\/jats:p>","DOI":"10.3390\/rs14030594","type":"journal-article","created":{"date-parts":[[2022,1,27]],"date-time":"2022-01-27T04:49:51Z","timestamp":1643258991000},"page":"594","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Variation Characteristics of Multi-Channel Differential Code Biases from New BDS-3 Signal Observations"],"prefix":"10.3390","volume":"14","author":[{"given":"Qiqi","family":"Shi","sequence":"first","affiliation":[{"name":"Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 200030, China"},{"name":"University of Chinese Academy of Sciences, Beijing 100049, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5108-4828","authenticated-orcid":false,"given":"Shuanggen","family":"Jin","sequence":"additional","affiliation":[{"name":"Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 200030, China"},{"name":"School of Remote Sensing and Geomatics Engineering, Nanjing University of Information Science and Technology, Nanjing 210044, China"},{"name":"School of Surveying and Land Information Engineering, Henan Polytechnic University, Jiaozuo 454000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,1,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"863","DOI":"10.1016\/j.asr.2014.02.007","article-title":"GNSS-Reflectometry: Forest canopies polarization scattering properties and modeling","volume":"54","author":"Wu","year":"2014","journal-title":"Adv. Space Res."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1139","DOI":"10.1007\/s10712-016-9385-z","article-title":"Terrestrial Water Storage Anomalies Associated with Drought in Southwestern USA from GPS Observations","volume":"37","author":"Jin","year":"2016","journal-title":"Surv. Geophys."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1701","DOI":"10.1016\/j.asr.2020.12.011","article-title":"Introduction to global short message communication service of BeiDou-3 navigation satellite system","volume":"67","author":"Li","year":"2021","journal-title":"Adv. Space Res."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1186\/s43020-019-0006-0","article-title":"Basic performance and future developments of BeiDou global navigation satellite system","volume":"1","author":"Yang","year":"2020","journal-title":"Satell. Navig."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"16","DOI":"10.1186\/s43020-020-00014-y","article-title":"PPP models and performances from single- to quad-frequency BDS observations","volume":"1","author":"Jin","year":"2020","journal-title":"Satell. Navig."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.jastp.2018.02.006","article-title":"Assessment of the NeQuick-2 and IRI-Plas 2017 models using global and long-term GNSS measurements","volume":"170","author":"Okoh","year":"2018","journal-title":"J. Atmos. Sol.-Terr. Phys."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"102","DOI":"10.1007\/s00190-020-01437-w","article-title":"A multi-frequency and multi-GNSS method for the retrieval of the ionospheric TEC and intraday variability of receiver DCBs","volume":"94","author":"Li","year":"2020","journal-title":"J. Geod."},{"key":"ref_8","unstructured":"Montenbruck, O., Hauschild, A., and Steigenberger, P. (2014, January 27\u201329). Differential code bias estimation using multi-GNSS observations and global ionosphere maps. Proceedings of the 2014 International Technical Meeting of the Institute of Navigation, San Diego, CA, USA."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"125","DOI":"10.1007\/s10291-018-0788-9","article-title":"Evaluation of three ionospheric delay computation methods for ground-based GNSS receivers","volume":"22","author":"Chen","year":"2018","journal-title":"GPS Solut."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"1670","DOI":"10.1016\/j.asr.2018.11.020","article-title":"Calibration errors in determining slant Total Electron Content (TEC) from multi-GNSS data","volume":"63","author":"Li","year":"2019","journal-title":"Adv. Space Res."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1919","DOI":"10.1007\/s11430-012-4454-8","article-title":"Extraction of line-of-sight ionospheric observables from GPS data using precise point positioning","volume":"55","author":"Zhang","year":"2012","journal-title":"Sci. China Earth Sci."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1007\/s00190-019-01332-z","article-title":"On the application of the raw-observation-based PPP to global ionosphere VTEC modeling: An advantage demonstration in the multi-frequency and multi-GNSS context","volume":"94","author":"Liu","year":"2019","journal-title":"J. Geod."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"19","DOI":"10.1007\/s00190-018-1135-1","article-title":"A modified carrier-to-code leveling method for retrieving ionospheric observables and detecting short-term temporal variability of receiver differential code biases","volume":"93","author":"Zhang","year":"2019","journal-title":"J. Geod."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"68","DOI":"10.1007\/s10291-021-01102-5","article-title":"Ionospheric VTEC and satellite DCB estimated from single-frequency BDS observations with multi-layer mapping function","volume":"25","author":"Su","year":"2021","journal-title":"GPS Solut."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"325","DOI":"10.1109\/TAES.1987.310829","article-title":"Ionospheric Time-Delay Algorithm for Single-Frequency GPS Users","volume":"AES-23","author":"Klobuchar","year":"1987","journal-title":"IEEE Trans. Aerosp. Electron. Syst."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1856","DOI":"10.1016\/j.jastp.2008.01.015","article-title":"A new version of the NeQuick ionosphere electron density model","volume":"70","author":"Nava","year":"2008","journal-title":"J. Atmos. Sol.-Terr. Phys."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"55","DOI":"10.1002\/navi.292","article-title":"The BeiDou global broadcast ionospheric delay correction model (BDGIM) and its preliminary performance evaluation results","volume":"66","author":"Yuan","year":"2019","journal-title":"NAVIGATION-J. Inst. Navig."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"19","DOI":"10.1186\/s43020-021-00050-2","article-title":"Status of CAS global ionospheric maps after the maximum of solar cycle 24","volume":"2","author":"Li","year":"2021","journal-title":"Satell. Navig."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"56","DOI":"10.1016\/j.asr.2020.09.011","article-title":"ESA UGI (Unified-GNSS-Ionosphere): An open-source software to compute precise ionosphere estimates","volume":"67","author":"Nava","year":"2021","journal-title":"Adv. Space Res."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"1010","DOI":"10.1080\/10020070412331344711","article-title":"A generalized trigonometric series function model for determining ionospheric delay","volume":"14","author":"Yuan","year":"2004","journal-title":"Prog. Nat. Sci."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"1671","DOI":"10.1016\/j.asr.2017.01.011","article-title":"The Multi-GNSS Experiment (MGEX) of the International GNSS Service (IGS)\u2014Achievements, prospects and challenges","volume":"59","author":"Montenbruck","year":"2017","journal-title":"Adv. Space Res."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"309","DOI":"10.1007\/s00190-015-0874-5","article-title":"Estimation of differential code biases for Beidou navigation system using multi-GNSS observations: How stable are the differential satellite and receiver code biases?","volume":"90","author":"Xue","year":"2016","journal-title":"J. Geod."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"1405","DOI":"10.1016\/j.asr.2020.05.019","article-title":"Estimation of the DCB for the BDS-3 new signals based on BDGIM constraints","volume":"66","author":"Zhu","year":"2020","journal-title":"Adv. Space Res."},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Li, M., and Yuan, Y. (2021). Estimation and Analysis of BDS2 and BDS3 Differential Code Biases and Global Ionospheric Maps Using BDS Observations. Remote Sens., 13.","DOI":"10.3390\/rs13030370"},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Wang, Q., Jin, S., Yuan, L., Hu, Y., Chen, J., and Guo, J. (2020). Estimation and Analysis of BDS-3 Differential Code Biases from MGEX Observations. Remote Sens., 12.","DOI":"10.3390\/rs12010068"},{"key":"ref_26","first-page":"448","article-title":"Estimation and analysis of the multi-frequency and multi-channel DCB for BDS-3","volume":"50","author":"Deng","year":"2021","journal-title":"Acta Geod. Cartogr. Sin."},{"key":"ref_27","doi-asserted-by":"crossref","unstructured":"Leick, A., Rapoport, L., and Tatarnikov, D. (2015). GPS Satellite Surveying, John Wiley & Sons.","DOI":"10.1002\/9781119018612"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"541","DOI":"10.1007\/s10291-012-0279-3","article-title":"M_DCB: Matlab code for estimating GNSS satellite and receiver differential code biases","volume":"16","author":"Jin","year":"2012","journal-title":"GPS Solut."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"871","DOI":"10.1016\/j.asr.2013.01.008","article-title":"Estimation of GPS instrumental biases from small scale network","volume":"54","author":"Ma","year":"2014","journal-title":"Adv. Space Res."},{"key":"ref_30","unstructured":"Schaer, S. (1999). Mapping and Predicting the Earth\u2019s Ionosphere Using the Global Positioning System, Astronomical Institute, University of Berne."},{"key":"ref_31","unstructured":"Schaer, S., Gurtner, W., and Feltens, J. (1998, January 9\u201311). IONEX: The ionosphere map exchange format version 1. Proceedings of the IGS AC workshop, Darmstadt, Germany."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"209","DOI":"10.1007\/s00190-015-0867-4","article-title":"Determination of differential code biases with multi-GNSS observations","volume":"90","author":"Wang","year":"2016","journal-title":"J. Geod."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"259","DOI":"10.5194\/angeo-34-259-2016","article-title":"Assessment of BeiDou differential code bias variations from multi-GNSS network observations","volume":"34","author":"Jin","year":"2016","journal-title":"Ann. Geophys."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"33499","DOI":"10.1038\/srep33499","article-title":"Global Ionospheric Modelling using Multi-GNSS: BeiDou, Galileo, GLONASS and GPS","volume":"6","author":"Ren","year":"2016","journal-title":"Sci. Rep."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"1840","DOI":"10.1007\/S11434-015-0911-Z","article-title":"Characterization of multi-GNSS between-receiver differential code biases using zero and short baselines","volume":"60","author":"Zhang","year":"2015","journal-title":"Sci. Bull."}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/14\/3\/594\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T22:08:24Z","timestamp":1760134104000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/14\/3\/594"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,1,26]]},"references-count":35,"journal-issue":{"issue":"3","published-online":{"date-parts":[[2022,2]]}},"alternative-id":["rs14030594"],"URL":"https:\/\/doi.org\/10.3390\/rs14030594","relation":{},"ISSN":["2072-4292"],"issn-type":[{"value":"2072-4292","type":"electronic"}],"subject":[],"published":{"date-parts":[[2022,1,26]]}}}