Research Of Low-voltage Power Line Noise Generator

Low-voltage power line carrier communication is one of the solutions of the'last mile'problem. Because it can make use of the existing power grid to provide high-quality net connection service to the consumers. Many companies and organizations home and abroad are researching in the area. To develop a high-speed power line communication that suits the situation in China, there should be research on the noise features of our low-voltage power line grid. So designing a low-voltage power line noise generator is very important to the research of the low-voltage power line carrier communication environment.The design approach is to divide the USB-bus noise generator into two parts. One is noise generator, the other is USB interface.In the design of the noise generator, the AD9708 with highest dating speed at 100MSPS as the DA converter. Data register is a high-speed SRAM, controller of the noise generator is a CPLD. It largely upgrades the system performance. CPLD is particularly suitable for lab research and product in small or medium batch producing or developing.Its programmability has largely reduced the difficulty in designing and debugging. In this design, CPLD chip design and controller interface design is a key point. This paper uses the Altera's Max+plusâ…¡, verilog-HDL, applied the software-hardware combined programming to solve the problem.The noise generator is used as a basic USB device, uses the control transfer and interrupt transfer. USBN9604 is chosen to be the interface chip. It is comply with the USB1.1 protocol.Micro-controller is the bond between the two parts, it acts as the USB controller in one way, and communicates with CPLD in the other. C8051F231 is the micro-controller, it has the RISC and low power advantages. The micro-controller communicates with the CPLD in parallel method, and SPI with the USBN9604. In which the SPI greatly simplifies the hardware circuit.Having combined the noise generator and the USB bus, it fully takes the advantage of the USB bus, promotes the performance-cost ratio, and easier for application.