Calibration errors on experimental slant total electron content (TEC) determined with GPS

摘要: The Global Positioning System (GPS) has become a powerful tool for ionospheric studies. In addition, corrections are necessary the augmentation systems required Navigation Satellite Systems (GNSS) use. Dual-frequency carrier-phase and code-delay GPS observations combined to obtain observables related slant total electron content (sTEC) along satellite-receiver line-of-sight (LoS). This observable is affected by inter-frequency biases [IFB; often called differential code (DCB)] due transmitting receiving hardware. These must be estimated eliminated from data in order calibrate experimental sTEC obtained observations. Based on analysis of single differences pairs co-located dual-frequency receivers, this research addresses two major issues: (1) assessing errors translated so-called levelling process, applied reduce ambiguities data; (2) short-term stability receiver IFB. conclusions achieved are: levelled systematic error, produced multi-path through procedure; IFB may experience significant changes during 1 day. magnitude both effects depends receiver/antenna configuration. Levelling found vary 1.4 units (TECU) 5.3 TECU. intra-day vaiations ranging 8.8 TECU were detected.