Design And Implementation Of Multi-frequencies Image Acquisition System

Modern production and scientific research have made an ever-increasing demand for videoimage acquisition system. Traditional analog image transmission system features simple processingfunctionality, discrete-component construction, low reliability, poor debugging performance, and lowadaptivity to special requirements. Real-time image sampling system based on FPGA technology cancomplete the hardware and software designs for the whole system on a single-chip FPGA. Thesystem is of a high integration and a high performance price ratio, and is easy to upgrade. Still, imageacquisition, processing, storage, and display are realized by hardware logic, which gives full play tothe FPGA parallel processing capabilities, especially suitable for image acquisition system with highreal-time requirements.In this paper, we studied the image transmission system used in multiple aircraft imagetransmission system, is a module of analog and digital mixed image transmission system, on aircraftthe analog image transmitted, while at the ground station analog images transform into digital images.This not only ensure the real-time performance of the system, and can form a digital imagematrix.The new image acquisition system requires a ground station to receive multi-channel imagesignal in parallel. As the broad bandwidth of the system, the huge computation amount bringsforward a large challenge for the real-time implementation. Consequently, we focus on the design ofthe multi-frequency real-time image acquisition system and its FPGA implementation. The maincontents of this dissertation are summarized as follows.Firstly, in this paper, beginning from the consideration of the application of the image acquisitionsystem, the characteristics of multi-frequency system are analyzed. Then combined with the existinghardware platform, gives the whole design and its modular design of the project.Secondly, Based on the characteristics of the signal processing system, this paper puts forwardan improved under the multi-channel digital frequency conversion structure. On the premise of meetthe requirements of system index, the FPGA logic resources consumption is reduced greatly; then，the basic theory and the FPGA implementation structure of digital beam former are studied.Thirdly, studied of the key factors influencing the performances of video decoding, and proposed a FPGA implementation structure of digital video decoder. Beside, designed themulti-channel image data forwarding and caching scheme, and implemented on the existinghardware platform.