Outdoor Magnetic Field Spatial Characterization Dataset Using a Quantum Magnetometer, Toronto (2025)

This dataset contains preprocessed outdoor magnetic field measurements collected using an SBQuantum SBQDM quantum magnetometer (optically pumped atomic magnetometer) at three outdoor locations in Toronto, Canada, during August–September 2025. Measurement Sites and Grid Configuration Measurements were conducted at Smythe Park (primary site), Scotiabank Road, and Toronto City Hall. At Smythe Park, data were collected across a 5×5 grid (1 m spacing, 25 points) over 10 repeated sessions under varying temporal and environmental conditions. At the two urban sites, a 2×3 grid (1 m spacing, 6 points) was used for a single session each. Data Format Each CSV file corresponds to one grid location and contains a continuous time-series recording of approximately 38 seconds. Each file includes three-axis magnetic field components (Bx, By, Bz) and the Euclidean magnitude (B_norm) as output by the vendor acquisition software. A total of 262 CSV files are included across 12 sessions. Preprocessing Thirteen anomalous samples with |B_norm| > 2×10⁶ nT were excluded prior to analysis. These samples correspond to sensor temperature-compensation transients and do not represent ambient field conditions. No other filtering or smoothing was applied. The manufacturer-provided static offset values (Ox, Oy, Oz) were subtracted from each axis component to compute the corrected magnetic flux density magnitude used in the associated study. Intended Use This dataset supports reproducibility of the analyses reported in the associated manuscript: Oh, C.-G. & Sultana, A., "Outdoor Magnetic Field Spatial Characterization Using a Quantum Magnetometer for GNSS-Complementary Positioning," IEEE Sensors Journal (under review), 2026. Analysis scripts are provided in the companion repository. Keywords quantum magnetometer, magnetic fingerprinting, outdoor magnetic field, spatial characterization, GNSS-complementary positioning, temporal stability, Toronto