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As the demand of astronomical observation rising, the telescope systems are becoming more and more complex. Thus, the observatory control software needs to be more intelligent, they have to control each instrument inside the observatory, finish the observation tasks autonomously, and report the information to users if needed. We developed a distributed autonomous observatory control framework named Remote Autonomous Control System 2nd, RACS2 to meet these requirements. The RACS2 framework uses decentralized distributed architecture, instrument control software and system service such as observation control service are implemented as different components. The communication between components is implemented based on a high-performance serialization library and a light-weighted messaging library.The interfaces towards python and Experimental Physics and Industrial Control System (EPICS) are implemented, so the RACS2 framework can communicate with EPICS based device control software and python-based software. Several system components including log, executor, scheduler and other modules are developed to help observation. Observation tasks can be programmed with python language, and the plans are scheduled by the scheduler component to achieve autonomous observation.A set of web service is implemented based on the FastAPI framework, with which user can control and manage the framework remotely.Based on the RACS2 framework, we have implemented the DATs telescope's observation system and the space object observation system.We performed remote autonomous observation and received many data with these systems., Comment: 22 pages, 16 figures

MARST (Multi-channel Antarctic Solar Telescope) aims to observe the Sun in multiple wavebands in Antarctica and will be China's first solar telescope in Antarctica. The telescope has two tubes, corresponding to Photosphere observation which uses 11 filters and Chromosphere observation in H{\alpha} waveband. The two tubes need to be coordinated to observe at the same time. The telescope will observe the Sun for a long time, so a self-guiding module is needed to improve sun tracking. Besides, performing solar specific flat-field exposure is necessary for analyzing. EPICS is introduced to control each hardware and an autonomous observation system based on RTS2 is designed under such demands. EPICS application modules are implemented for each device: telescope mount & focuser, filter wheel, H{\alpha} filter, dome with webcams, Andor CCD and PI CCD. We also integrate EPICS modules into RTS2 framework with an XML format configuration. To control these applications autonomously we have developed a RTS2 executor module where two plan classes are instantiated to control two sets of filters and CCDs, and to ensure only one could control the mount at the same time. Different types of observation plans are designed to describe different series of processes with different priorities. To improve sun tracking, we calculate the centroid of each image to get the offset, then apply the correction to the telescope during observation process. For frontend users, a GUI based on PyQt5 and QML is implemented and connects to rts2-httpd and rts2-proxy modules so that users can control devices, check images and get logs.

Tibet is known as the third pole of the earth, as high as the South Pole and North Pole. The Ngari (Ali) observatory in Tibet has the advantage of plenty of photometric night, low precipitable water vapor, high transmittance, good seeing. It is a good site, and promising to be one of the best place for infrared and submillimeter observations in the world. However, there is no data available for sky background brightness in such place, which restrict the astronomical development of the sites. In the near infrared band of J, H, Ks, a NIR sky brightness monitor (NISBM) is designed based on InGaAs photoelectric diode. By using the method of chopper modulation and digital lock-in amplifier processing, the SNR (Signal Noise Ratio), detectivity and the data acquisition speed of the device is greatly improved. For each band of J, H, Ks, an independent instrument is designed and calibrated in laboratory. The NISBM has been installed in Ngari observatory in July of 2017 and obtained the first data of NIR sky brightness at Ngari observatory., Comment: 19 pages,18 figures

The Near-infrared Sky Brightness Monitor (NIRBM) aims to measure the middle infrared sky background in Antarctica. The NIRBM mainly consists of an InGaAs detector, a chopper, a reflector, a cooler and a black body. The reflector can rotate to scan the sky with a field of view ranging from 0{\deg} to 180{\deg}. Electromechanical control and weak signal readout functions are accomplished by the same circuit, whose core chip is a STM32F407VG microcontroller. Considering the environment is harsh for humans in Antarctica, a multi-level remote control software system is designed and implemented. A set of EPICS IOCs are developed to control each hardware module independently via serial port communication with the STM32 microcontroller. The tornado web framework and PyEpics are introduced as a combination where PyEpics is used to monitor or change the EPICS Process Variables, functioning as a client for the EPICS framework. Tornado is responsible for the specific operation process of inter-device collaboration, and expose a set of interfaces to users to make calls. Considering the high delay and low bandwidth of the network environment, the tornado back-end is designed as a master-and-agent architecture to improve domestic user experience. The master node is deployed in Antarctic while multiple agent nodes can be deployed domestic. The master and agent nodes communicate with each other through the WebSocket protocol to exchange latest information so that bandwidth is saved. The GUI is implemented in the form of single-page application based on the Vue framework which communicates with tornado through WebSocket and AJAX requests. The web page integrates device control, data curve drawing, alarm display, auto observation and other functions together., Comment: Many revision were done after the submission, and the result in this paper may need more correction

The upgrade of ATLAS Liquid Argon Calorimeter (LAr) Phase-1 trigger requires high-speed, low-latency data transmission to read out the Lar Trigger Digitizer Board (LTDB). A dual-channel transmitter ASIC LOCx2 have been designed and produced. In order to ensure all the LOCx2 chips behave properly, a Quality Assurance needs to be conducted before assembly. The problem I was trying to solve in this project is to yield a clock signal with continuously adjustable frequency and phase offset to generate and control an eye diagram for the QA. By configuring the registers of an any-frequency generator IC, Si5338, the clock signal whose frequency range from 5MHz to 200 MHz have been properly produced. For the purpose of further development, a C-language based DLL which packs up the function of adjusting frequency and setting phase offset was designed and built, and several evaluation was performed to ensure the robustness of DLL.

A near-infrared (NIR) measurement based on digital orthogonal vector lock-in amplifier (LIA) is present in this paper. NIR sky background radiation is very weak. To detect the signals obscured by noise, the best way achieved is to use a chopper to modulate the detected signal and using a LIA to demodulate. The effect of 1/f noise of detector, dark current and other noises can be reduced to get sufficient signal-to-noise ratio (SNR). The orthogonal vector LIA can avoid the phase shift on the accuracy of measurement by two orthogonal components. In order to simplify the system, a digital algorithm is adopted to realize the LIA which is operated in a microcontroller with ARM cortex-M4. Data is obtained through ADC and the signal of detector is amplified and filtered. Then the phase sensitive detection (PSD), low-pass filter (LPF) and amplitude phase calculation are performed. The digital method can greatly simplify the circuit, and conveniently adjust the time constant of the LPF to realize the different equivalent noise bandwidth (ENB). The algorithm has the specification of high precision, flexible usage, simple implementation and low computation resource. By using this method, the weak infrared signal submerged by the noise can be obtained, which extremely improves the detection capability of the system.