Design And FPGA Realizaiton Of Link-22 Data Link Signal Generator

Link-22 data link is called “NATO improved Link-11 data chain”,it is a kind of anti interference chain of confidential data over the horizon communication through the relay system,can be in the water,surface of the water,land and air exchange between different platforms,real-time target tracking information transmission control command.Signal generator has very important application in communication,aerospace and electronic measurement field.It can be not only standard transmit signal but also correct signal or measurement signal for comparison.With the development of software radio,integrated circuit technique and extensive use of FPGA,the digital realization of the signal source has become a trend.The design of signal source has great improvement in aspects of precision,complexity or easy to modification.Link-22 data link uses RS coding,interleaving,QPSK modulation,8PSK modulation,MQAM modulation,frequency hopping and so on.This thesis analyzed the Link-22 data link based on the project of CLP XX,and completes the design,implementation and testing of the Link-22 data link signal source system according to the needs of the project.This thesis analyzes the standard and Link-22 data link protocol,including data link message type,package structure,F and FJ series of messages;the design and implementation of Link-22 data link encryption,encoding technology and block interleaving,32 bit encryption using pseudo random encryption,encoding technology using the provisions of the standard Link-22 data link RS(96,76)encoding,block interleaver with 8 rows and 12 columns;The slot encapsulation of Link-22 data link,including data link data symbols and symbol detection and frequency hopping package two mode;AD9957 inverter to realize multi modulation based on design,including shaping filter,three kinds of modulation: QPSK,8PSK,16 QAM,32QAM,64QAM;The design and Implementation of Link-22 data link technology and radio frequency hopping step,the radio frequency range 225-236 MHz,1MHz step;In the VS2012 compiler environment,the upper computer interface.Finally,I completed the output signal by using vector analyzer all test numbers and output signal of the successful demodulation.The measurement shows that all kinds of modulation EVM and all other project requirements are completed with high index.