# An Observation Scheduling System for Radio Telescope Array
## 1 Introduction  
The Five-hundred-meter Aperture Spherical radio Telescope (FAST) [1], located at Pingtang, Guizhou, China, is currently the largest single-dish radio telescope in the world and almost approaches the sensitivity limits of single-dish radio telescopes [2, 3]. In the future, as we look ahead, developments in telescope array technology will significantly improve both sensitivity and spatial resolution, two crucial factors in astronomical observations. Presently, many radio telescope arrays are under construction or have already been completed and put into use internationally, such as the Canadian Hydrogen Intensity Mapping Experiment (CHIME) [4], the American Deep Synoptic Array (DSA) [5], and the Square Kilometer Array (SKA) radio telescope [6]. To ensure the smooth progress of radio astronomical observations, it is essential to accurately predict the visible time and relative position of the target at the telescope array that is required for an observation project. However, most existing software for predicting sources with different radio telescope arrays is either not publicly available or lacks completeness. Moreover, the problem of prioritizing multiple targets for observation remains unresolved. Additionally, given the varying samples (commonly referred to as \(uv\) coverage in radio astronomy) of the target in different array configurations, obtaining a radio telescope array layout with maximum coverage through numerical simulations is crucial. The \(uv\) coverage represents the coordinate points of \(u\) and \(v\) on the \(uv\) plane, which are determined by transforming the coordinates of the baselines of the telescope array. Here, the line connecting each pair of telescopes in the arrayis called a baseline. Therefore, developing a highly adaptable antenna array observation simulation system is of significant importance for radio astronomy observations. In astronomical observations, planning the observation of targets traditionally involves manually scheduling based on factors such as their rise and set times and the significance of the sources. This process can be time-consuming and resource-intensive. Currently, there is not a universally accepted software for simulating radio sources behavior, when people perform observations. Most of the existing software has successfully used sky coordinates as input to perform observations. However, they were independently developed, are not publicly available, and are tailored only to the specific array for which they were developed, requiring significant manual effort to create observation plans. The publicly available software is the source position predictor on the Parkes Observatory website ([[https://www.parkes.atnf.csiro.au/observing/utilities/coord.php/](https://www.parkes.atnf.csiro.au/observing/utilities/coord.php/)]([https://www.parkes.atnf.csiro.au/observing/utilities/coord.php/](https://www.parkes.atnf.csiro.au/observing/utilities/coord.php/)), accessed on 11 October 2024) and SCHED ([[https://pypi.org/project/pythonSCHED/](https://pypi.org/project/pythonSCHED/)]([https://pypi.org/project/pythonSCHED/](https://pypi.org/project/pythonSCHED/)), accessed on 11 October 2024) developed by the National Radio Astronomy Observatory (NRAO) in the United States. The Parkes software can only predict the elevation of a single target and cannot handle multiple sources simultaneously, while the SCHED software only provides trajectory prediction and lacks intelligent scheduling capabilities. Additionally, there are some non-public simulation software, such as the observation summary page for the 100-meter Effelsberg telescope ([https://eff100 mwiki.mpifr-bonn.mpg.de/doku.php/](https://eff100 mwiki.mpifr-bonn.mpg.de/doku.php/), accessed on 11 October 2024) in Germany and the Dynamic Scheduling System (DSS) [7] for the Green Bank Telescope (GBT) in the United States.