基于以太网的射电天文制冷接收机的监视系统

An Ethernet-based Monitoring System of Cryogenic Receivers on a Radio Telescope

制冷接收机是射电望远镜的核心设备,它是否正常工作直接决定望远镜观测的效果。制冷接收机的制冷温度和杜瓦真空度是反映接收机是否正常工作的最重要、最直接的指标之一。因此实现制冷接收机制冷温度和杜瓦真空度的远程实时监控,及时了解接收机是否正常工作对保证射电望远镜正常运行、提高观测效率有重要意义。为乌鲁木齐天文站25m射电望远镜1.3cm制冷接收机研制的一套基于单片机和以太网的数据采集和数据传输的远程监视系统,实现了制冷接收机制冷温度和杜瓦真空度的远程实时监控。该系统采用了美国ATMEL公司生产的8位单片机AVR ATmega16、Microchip Technology公司生产的ENC28J60以及MAXIM公司生产的MAX7219,实现对射电天文制冷接收机制冷温度和杜瓦真空度的数据采集,并利用以太网传输数据实现了远程实时监控接收机的制冷状态。阐述了以太网数据采集及远程监控电路的设计原理及其实现方法。该系统首次在国内大型射电望远镜上实现了对制冷接收机工作状态的远程实时监控,对于保证乌鲁木齐天文站25m射电望远镜1.3cm波段的观测效果有重要作用。

A cryogenic receiver is a key equipment on a radio telescope. The temperature of cryogenic receiver and the vacuum level of its dewar are two important factors for measuring whether the receiver works properly and thus whether the radio telescope functions normally. Therefore, it is necessary to monitor the temperature and vacuum level of the cryogenic receiver. We designed and made a remote-monitoring system for a new 1.3cm dual polarization cryogenic receiver, which will be installed on the 25m radio telescope of the Urumqi Station. This paper describes the method of how to design and make this system. The monitoring system is controlled by a single-chip microcomputer. The system acquires data, transfers data, and remotely monitors the radio astronomical receiver via an ethernet. The microcomputer, ethernet controller, and drive circuit of the system are the 8-bit MCU AVR ATmegal6, ENC28J60, and MAX7219,respectively. The system monitors the cryogenic receiver by reading its temperature and vacuum level of dewar. This system includes the network interface circuit, microcontroller circuits, RAM memory circuit, and EEPROM memory circuit. Overall, the system achieves remote real-time monitoring of the working status of a cryogenic receiver on a large radio telescope for the first time in China. It is particularly important for ensuring the effective observation with the 25m radio telescope at the Urumqi Station through 1.3cm wavelength bands.