FPGA-based INET Internet Radio Interface Extension Technology Research

MDS Inc. in the Tibet crisis prevention and emergency rescue project is a regionalprivate network (iNET) to establish a wireless information network system, used tosolve the communication problem monitoring points to3G signal coverage better. Butthe MDS iNET300series are equipped with interfaces can not meet the actual needs, soit is necessary to extend the existing iNET300interface, for this purpose the researchtopic of this article for the designed is FPGA-based network interface extensions.Through the research of interface converter at home and abroad, due to the use ofthe background and needs of different existing interface conversion and extensionproducts and interface conversion and expansion research can not meet the subjectrequirements, based on this research purpose of this subject launches for the topicdirection, different communication device interface tend to use differentcommunication protocols, different communication interface hindering thetransmission of data, an important way to solve this problem is the protocol conversion,the paper presents the design of a FPGA-based network interface expansion. In recentyears, with the FPGA increasing performance improvement and on-chip programmablesystem (System On Programmable Chip SOPC) technology continues to develop,SOPC for data conversion is a new way, The research content of this paper is thecombination of the Nios II soft-core processor, designed a configurable, universal, easyto transplant,iNET Internet radio interface expansion module.This paper In-depth research on multi-serial and Ethernet conversion systemarchitecture and key technologies designed, in the introductory section of this articledescribes the conversion and expansion of the existing different interfaces, surveyresearch of the domestic and foreign research situation and new trend of development, establish the content of the research projects and existing research innovation of thispaper. In the main part of this paper, Firstly the function and the technical problem ofextended design based on iNET Ethernet interface of FPGA are analyzed, introducedthe involved two interface protocol RS232and TCP/IP, analyze and compare the twokinds of protocols,and introduce the hardware system, including the the hardwareperipherals board and the development board as well as the hardware platformstructures and data link path flows. Then the two chapter introduces the softwaresystem of Ethernet interface design, Chapter III of the software programmingapplications and theory are introduced, including the introduction of the softwaredevelopment environment Quartus II, ModelSim, SOPC Builder, Eclipse, developed aMultiport Serial conversion module communication protocol based on MODBUS-RTU,introduced the adaptive algorithm related theories, and to explore and study the serialmodule self-adaptive bandwidth to achieve on its basis, and finally describes thenetwork interface extensible software design architecture, the whole design is dividedinto two modules, respectively is com_fifo serial port module and nios_LAN_UARTserial port Ethernet switching module, namely, Provides a theoretical basis for the nextelaborated based on the SOPC network interface extension designed to achieve. Thefourth chapter is specific network interface extension design software to achieve, andthen introduced the serial Ethernet converter module data conversion, and then from theinterface realization of proprietary chip ENC28J60, function and control of theMAX232soft core structures,build for soft-core configuration CPU, SDRAM,EPCS,JATG peripheral circuits to generate the soft-core, based on combination ofEthernet and serial communication protocol TCP/IP and RS232achieve a NiosIIsoft-core processor under Embedded Serial Ethernet network interface convertermodule development. In order to achieve multi-serial and Ethernet conversion, torealize multi-serial modules are studied, the entire module is divided into the mainserial transmission module and the main serial receiver module, combined with theadaptive algorithm, realize the adaptive bandwidth throttling between themulti-serialport with a single serial port data conversion. Finally,do the testing frommodule and system aspects of the Network expansion module, verify the function of thesubject and the possibility of realization.