Polyphase based wideband digital adjacent SSB converter of IF signal

In radio interferometry, the image and baseline sensitivity are specific to the antenna - its effective collecting area, the antenna system noise and the observing bandwidth. Obviously, the sensitivity can be improved by a larger total observing bandwidth if the collection area and noise of receiver systems remain the same. Currently, ADC sampling rate in the wideband digital backend has reached more than 4 GHz, but the high-speed digital transmission and real-time signal processing are still the bottlenecks in the broadband processing. This paper analyzes the architectures of wide band adjacent SSB converter. It presents a common deducing method for over-sampling, multirate signal processing to generate a digital SSB signal, based on the decimation structure of a real bandpass signal, to acquire an efficient architecture based on DFT polyphase filter banks, which segments each IF into 2 n adjacent frequencies to USB and LSB channels. This leads to a hardware-efficient implementation of continuous spectrum observation which can greatly reduce the hardware complexity and improve the utilization of hardware resources. A simulation model of this architecture of poly-phase filter banks is designed and implemented using MATLAB.