关键词 : 多路信号复用 数字复接 基带发信系统
Abstract
Baseband system model for transmitting information of multi_channel signal multiplexing usually is composed of two components, digital signal multiplexing unit and HDB3_encoder unit. digital signal multiplexing unit mainly is composed of timing generator and information coding receiver which can switch signal. HDB3_encoder unit mainly is composed of inserting_V part, patching_B part and the part which can switch unipolar signal to bipolar signal.
In the past the development of design, as no new FPGA/CPLD devices and the corresponding software, therefore, the digital communication circuit is very difficult to develop, that require long designing cycle, significantly restrict its use and popularize, however, in pace with microelectronics and computer software technology development, now researcher can use new FPGA/CPLD devices to design arbitrary digital circuit that they want to realize, greatly increasing the efficiency of the development.
This design project for graduation was to use VHDL to describe a baseband system for transmitting information of four_channel signal multiplexing by programming, and then download to FPGA device, only that, the chip of system for transmitting information of multi_channel signal multiplexing will be realize successfully.
Keywords: multi_channel signal multiplexing,digital multiplexer,baseband system for transmitting information