The Application And Optimization Methods For Network Interface In Digital TV STB

Based on DVB-C, cable digital television is in the process of the overall translation in China. With the rapid translation, there will be more and more complex problems.The most prominent one is the complex and ever-changing DVB-C network environment in old city districts and rural areas. So the problem of how to choose a suitable and optimize design for high-frequency tuner that can continuously improve the Network Interface of the STB and adapt to different regions of complex network environment will be faced to all digital television STB designers.This paper mainly focuses on the high-frequency module of DVB-C STB,research has two objectives: ensure high-frequency full- frequency consistently and improve the ability of front-end set-top box interface to anti-jamming.The paper chooses the QAMi5516 and STx5105 system of ST Micro as a research platform, and chooses the LG-TDCH-Z001F and PHILIPS-CU1216LS as the research objects. By reserching on both hardware circuit and driver program of the Network Interface of STB,the author analyzed and put forward a scheme that can optimize the performance of the high-frequency tuner.In the aspect of hardware circuit, the topic mainly researched on the electromagnetic interference, electromagnetic radiation and PCBLayout of Network Interface circuit. As for the software, the topic mainly researched on the driver program and embedded operating system of high-frequency tuner. By reserching on carrier recovery,the author solve the contradiction between frequency capture range and sweep precision. To research on both software and hardware, the paper conludes various problems which should be noticed and different methods of optimizing the performance of Network Interface of the applications of high-frequency tuner.Finally,the author alleged the methods to improve the capacity of anti-disturbance for STB Network Interface.