Every three years, the International VLBI Service for Geodesy and Astrometry (IVS) has carried out a continuous observing campaign (CONT) with the goal of demonstrating state-of-the art Very Long Baseline Interferometry (VLBI) observing since 2002. In 2017, the campaign was unique in two respects: three independent networks ran simultaneously and one of the networks was a demonstration of new VLBI Global Observing System (VGOS) technology. Two 14-station legacy station networks, CONT17-L1 and CONT17-L2 observed in S/X mode and the third network, CONT17-VGOS, consisted of five stations observing in VGOS broadband mode. We investigated the differences between Earth Orientation Parameters (EOPs) and scale parameters estimated from the simultaneous observing sessions of the three networks. Prior studies could not determine VLBI EOP precision or VLBI network biases within the VLBI technique. For CONT17, EOP (X-pole, Y-pole, and UT1) biases between the CONT17-L2 and CONT17-L1 networks were \(-11\pm 12\) \(\mu \)as, \(-19\pm 13\) \(\mu \)as, \(-1.1\pm 1.0\) \(\mu \)s, which are at the 1-sigma level. X-pole, Y-pole, and UT1 biases between the CONT17-VGOS and CONT17-L1 networks were \(-108\pm 24\) \(\mu \)as, \(-17\pm 23\) \(\mu \)as, \(1.4\pm 0.6\) \(\mu \)s. Three corner hat analysis of the CONT17-L1, CONT17-L2, and Global Navigation Satellite System (GNSS) series yielded X and Y polar motion precisions of CONT17-L1: 19.8 \(\mu \)as, 22.4 \(\mu \)as; CONT17-L2: 41.0 \(\mu \)as, 35.2 \(\mu \)as; GNSS: 19.8 \(\mu \)as, 15.0 \(\mu \)as. Session scale parameter precisions of the CONT17-L1 and CONT17-L2 networks based on the standard deviation of their respective scale series are 0.45 ppb and 0.30 ppb. Baseline length repeatabilities for each of the networks indicate that the length precision versus length of the VGOS network is about 0.4 ppb compared to 0.5 ppb for the CONT17-L2 network and 0.6 ppb for the CONT17-L1 network for baselines of length less than 10,000 km.

自 2002 年以来，国际 VLBI 大地测量和天体测量服务 (IVS) 每隔三年开展一次连续观测活动 (CONT)，目标是展示最先进的超长基线干涉测量 (VLBI) 观测。2017 年，该活动在两个方面是独一无二的：三个独立的网络同时运行，其中一个网络展示了新的 VLBI 全球观测系统 (VGOS) 技术。两个 14 站传统站网 CONT17-L1 和 CONT17-L2 以 S/X 模式观测，第三个网络 CONT17-VGOS 由 5 个以 VGOS 宽带模式观测的站组成。我们调查了地球定向参数 (EOP) 和从三个网络的同时观测会话估计的尺度参数之间的差异。先前的研究无法确定 VLBI 技术中的 VLBI EOP 精度或 VLBI 网络偏差。对于 CONT17，CONT17-L2 和 CONT17-L1 网络之间的 EOP（X 极、Y 极和 UT1）偏差为\(-11\pm 12\) \(\mu \) as, \(-19\pm 13\) \(\mu \) as, \(-1.1\pm 1.0\) \(\mu \) s ，它们处于 1-sigma 水平。CONT17-VGOS 和 CONT17-L1 网络之间的 X 极点、Y 极点和 UT1 偏差为\(-108\pm 24\) \(\mu \)，如\(-17\pm 23\) \( \mu \)作为，\(1.4\pm 0.6\) \(\mu \) s。CONT17-L1、CONT17-L2 和全球导航卫星系统 (GNSS) 系列的三角帽分析得出 CONT17-L1 的 X 和 Y 极坐标运动精度：19.8 \(\mu \) as, 22.4 \(\mu \ )作为；CONT17-L2：41.0 \(\mu \)作为，35.2 \(\mu \)作为；全球导航卫星系统：19.8\(\mu \)作为，15.0 \(\mu \)作为。CONT17-L1 和 CONT17-L2 网络的会话规模参数精度基于其各自规模系列的标准偏差为 0.45 ppb 和 0.30 ppb。每个网络的基线长度重复性表明，对于长度小于 10,000 公里的基线，VGOS 网络的长度精度与长度的关系约为 0.4 ppb，而 CONT17-L2 网络为 0.5 ppb，CONT17-L1 网络为 0.6 ppb .