Design And Implementation Of Pc-based Digital Tuner Test System

Measurement technology has its history such as Analog Instrument, Component divided Instrument, Digital Display Instrument, Intellectualized Instrument, Auto-measurement System and Virtual Instrument assumably. Analog Instrument, Component divided Instrument, Digital Display Instrument are traditional instrument which have come through a long development time. Correspondingly Intellectualized Instrument, Auto-measurement System and Virtual Instrument are called modern measurement system which develop with the development of microelectronic technology and computer technology. Especially since 1970s Auto-measurement System and Virtual Instrument have the character of autoimmunization, intelligentization and can be programmed, they are set up by general hardware platform which consist of computer and instrument hardware and software. They intenerate traditional instrument's hardware and the function of measurement and testing and calculating based on the function of computer software and hardware. So, with the development of computer technology and measurement technology, the technology of measurement and control have a fast progress, and the instrument of measurement and control improve as intelligentization, miniaturization and network. The popularization of computer make it possible that PC instrument progress fast which have a wide appliance field, and it is becoming a fashion and direction.At the same time, with the development of digital video technology, DVB have become some necessary technology during which TV enterprise step from time of analogs to digital. DVB is a system by digital communication, in which digital tuner is one of main component. So the capability of digital tuner wound influence the effect of DVB receiver. It is necessary to inspect all sorts of specification of digital tuner. And it is possibility and have wide appliance field to build a digital tuner measurement system which have complete function, is simple to operate and economical based on PC which have been used widely.It's a mature technology that Virtual Instrument measure some parameter in PC technology. However, with the development of technology and practical demand, it is necessary that a measurement system is multi-task system, but a finishing Virtual Instrument for some task is limited, it is difficult to embed additional task into the system. We design a measurement system based on PC in PC directly. The system connect IIC bus of digital tuner and parallel port of PC with interface circuit. Software keep communications between tuner and PC, control tuner working, monitor the status of tuner, and evaluate the tuner's input and output to measure the capability of tuner such as BER and AGC etc.