The Key Technology Analyses and Researches of the Sparse Array in VHF Band in Radio Astronomy

VHF (Very High Frequency) band is one of important observation bands in Radio astronomy field. In this band, we usually use the array to form phased array telescope. In another hand, sparse array has more space resolution and lower side lobe level comparing with the regular array. Furthermore, based on array integrated optimization algorithms, we can effectively form the main beam and reject the Maximum side lobe levels and far side lobe levels. In this paper, at first, we review the development and research status of VHF sparse array in radio astronomy filed and analyze difficulties. The second, we promote a pipeline for sparse array building. The first step is constructing the optical elements configuration based on some optimization algorithms. And then, we promote a signal processing structure based on high performance computing severs and FPGA (Field Programmable Gate Array) SOPC (System On Programmable Chip) platform. In this platform, taking advantage of strong computing capability, in the GPU embedded in severs can compute the weighting parameters of different elements and different frequency channels. And then, transmitting these parameters through the high-speed bus and delivery them to each element in FPGA SOPC.We also analyze the data rate with multi-beams that can transmit the weighting parameters in real-time. This work can provide a technical base for future large-scale VHF array building.