Mitigation of radio frequency interferences (RFI) is crucial for improving the quality of collected radio observations. For the instruments working in the decimeter and meter ranges – LOFAR (LOw Frequency ARray) is a good example – RFI is particularly vexing thus the widest possible knowledge of man-made emissions in the vicinity of radio telescopes is highly desirable. The results of the measurements of RFI performed at the LOFAR PL612 station in Bałdy as well as the Radio Astronomical Observatory in Piwnice and the Astronomical Observatory and Astronomical Education Centre in Białków are shown and a comparative analysis has been carried out. Owing to this, solutions either to suppress RFI sources or to filter out undesirable signals in the spectra have been proposed. The results will be particularly important for the development of the LOFAR system and the extension of its usable waveband to the 10–30 MHz range. The presented measurement results also suggest the necessity to introduce a continuous RFI monitoring at LOFAR sites.

减轻无线电频率干扰 (RFI) 对于提高收集的无线电观测质量至关重要。对于在分米和米范围内工作的仪器——LOFAR（低频阵列）是一个很好的例子——RFI 尤其令人烦恼，因此非常需要尽可能广泛地了解射电望远镜附近的人造发射。显示了在 Bałdy 的 LOFAR PL612 站以及 Piwnice 的射电天文台和 Białków 的天文台和天文教育中心进行的 RFI 测量结果，并进行了比较分析。因此，已经提出了抑制 RFI 源或滤除频谱中不需要的信号的解决方案。这些结果对于 LOFAR 系统的开发和将其可用波段扩展到 10-30 MHz 范围尤为重要。所呈现的测量结果还表明有必要在 LOFAR 站点引入连续 RFI 监测。