The high efficient architectures of VLBI wideband DBBC

The VLBI data acquisition backend plays an important role in the VLBI station. Recently, based on advances in digital hardware like ADC (Analog-to-Digital Conversion), DSP (Digital Signal Processing), FPGA (Field Programmable Gate Arrays) and so on, it has become practical to sample and digitally process the intermediate frequency signal directly. DBBC (Digital Base-Band Converters) will replace ABBC (Analog Base Band Converters) in the VLBI data acquisition backend. A wide band digital VLBI Digital Backend using poly-phase filter banks segments each 512MHz IF into 2n adjacent frequency channels spanning the 512MHz IF bandwidth, This paper analyzes the architectures of VLBI wideband DBBC and use a common deducing method to acquire an efficient architecture based DFT polyphase filter banks to realize wideband DBBC. the arithmetic operations and complexity is compared between the different architectures. A simulation model of poly-phase filter banks is designed. All the xperimental results show that the model is valid and practical.