Hardware Correlator Development at SHAO

摘要

Very Long Baseline Interferometry (VLBI) is an important radio astronomy technology, it has high spatial resolution, is widely used in deep space probes high precision measurements. Correlator is the VLBI core data pre-processing equipment, is a complex high speed signal processing system. In recent years, with the development of the Field Programmable Gate Array (FPGA) technology, a lot of high performance digital signal processing platforms based on FPGA chip have appear. In Shanghai astronomical observatory, we have designed a series of hardware correlators based on FPGA and used in Chinese lunar project Chang'E 1, Chang'E 2, Chang'E 3 and Chang'E 5T1 mission. In the following lunar project and further Mars project in China, multiple orbits spacecraft tracking will be widely used, the tracking will be more complex. But because of the limitation of the hardware platform, the real time processing speed and precision is limited, can not meet the requirements of the following up Chinese Lunar project and further Mars project. Recently with the cooperations with Joint Institute for VLBI in European (JIVE), a high performance processing platform called Uniboard is developed. The next generation hardware correlator based on Uniboard has designed in Shanghai astronomical observatory. The project designed a real time high resolution multiple orbit correlator based on Uniboard platform, and has participated in several observations, it will be used in Chang'E 4 mission which is plan to launch this year. The project also plan to get experience for designing the cost effective low power next generation hardware correlator and research the spectral line VLBI, pulsar and deep space exploration data processing technology.