Ionospheric currents have widely been investigated by using magnetic measurements from low-Earth orbiting satellites. However, the assumptions of deriving currents from the magnetic measurements have not always been well considered. In this study we performed a detailed analysis of the ionospheric radial current (IRC) and inter-hemispheric field-aligned current (IHFAC) estimates at equatorial and low latitudes derived from the single-satellite and dual-spacecraft (dual-SC) approaches of European Space Agency (ESA's) Swarm constellation. Data considered cover a 5-year period, from 17 April 2014 to 16 April 2019. We found for most of the cases, the IRCs and IHFACs derived from both approaches show consistent latitudinal profiles. However, there are several cases with discrepancy exceeding 5 nA/m 2 between two approaches. On average, the diurnal variations of IHFACs from both approaches agree well with each other for all seasons. But the amplitudes of single-satellite results reach only about 70% of those from the dual-SC. This difference is attributed to the fact that only the magnetic field By component is utilized in the single-satellite approach, while both B_x and B_y components are considered in the dual-SC approach. Above the magnetic equator, the IRCs derived from single-satellite approach show clear tidal signatures, while such signature cannot be found in the IRCs from dual-SC approach. We interpret these tidal-signature of IRCs as spurious results, caused by equatorial electrojet contributions to the ΔBy component. The dual-SC derived IRCs show notable differences between ascending and descending orbits. Such differences might be due to a violation of the assumed perfect calibration of Swarm A and C. We suggest a systematic spacecraft-fixed bias in the along-track magnetic field component (B_x) between Swarm A and C. B_y interpreting the IRC differences, we obtain bias values of ΔB_x reaching 1 nT. Our results reveal that ionospheric currents are better ch
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