Intelligent Wireless Image Transmission System

Along with the development of Wireless Communication Technology, there is higher and higher requirement on the video transmission, especially on the Broadband Intelligent Transport Systems. The purpose of this topic is in order to solve the problems that conventional video transmission systems have no characteristics of a large bandwidth and intelligence. So, there are greater research value and practical value on this topic.This topic describes the status of wireless image transmission system, firstly researches OFDM (Orthogonal Frequency Division Multiplexing), analyzes the synchronization technology of OFDM System, discusses their application of wireless image transmission and establishes the modulation of the transmission based on OFDM. Then it introduces the high-speed signal sampling theory, analyzes kinds of high-speed signal sampling modes such as band-pass sampling, parallel sampling and alternate sampling, quadrature sampling, equivalent sampling of the periodic signal and so on. At last it analyzes the aperture jitter, the impact on A/D conversion accuracy and the measures of reducing the aperture jitter. According to the analyses above, this system uses under-sampling methods. Basis for the requirements of intelligent wireless image transmission system, this topic designs the general framework of the system, then refines RF analog front-end receiver, establishes under-sampling down-conversion architecture. The system architecture designing of the broad receiver RF front-end is the main line, and then it researches and designs LNA, MIXER module, AGC module, BPF, phase-locked local oscillator source module respectively. It designs and produces every module with the latest design techniques and then debugs the circuits, at last makes it to meet the design requirements.