This paper proposes a new technique, namely Phase bias-based Small Grid Model (PSGM), to derive absolute ionospheric vertical total electron content (VTEC) with observations of Global Navigation Satellite System Earth Observation Network of Japan (GEONET). The proposed technique deals with the phase observations alone without handling the pseudoranges, which reduces the noise in VTEC estimation. A new parameter, the arc bias ( B arc ), is introduced to combine the phase ambiguities and differential phase biases. To solve B arc , equations are constructed under the assumption that the VTEC is identical in the same 0.1° × 0.1° grid. The performance of PSGM is evaluated with the observations in solar maximum year 2014. The root mean square error (RMSE) of PSGM is 0.40 TECU in average, the maximum RMSE is 0.73 TECU and the minimum RMSE is 0.26 TECU. The fitting accuracy of the VTEC results is improved compared with most of the existing methods.

中文翻译：

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使用 GEONET 进行高精度 VTEC 推导

本文提出了一种新技术，即基于相位偏置的小网格模型 (PSGM)，通过日本全球导航卫星系统地球观测网络 (GEONET) 的观测得出绝对电离层垂直总电子含量 (VTEC)。所提出的技术仅处理相位观测而不处理伪距，这降低了 VTEC 估计中的噪声。引入了一个新参数，即电弧偏置 (B arc ) 来组合相位模糊度和微分相位偏置。为了求解 B arc ，在假设 VTEC 在相同的 0.1° × 0.1° 网格中相同的情况下构建方程。PSGM的性能通过2014年太阳活动极大年的观测进行评估。PSGM的均方根误差（RMSE）平均为0.40 TECU，最大RMSE为0.73 TECU，最小RMSE为0.26 TECU。