The Research And Development Of Real-Time I/Q Baseband Signal Generator

This paper comes from breadthwise scientific research which is about "TheResearch of Real-Time IIQ baseband signal.generator". It is demanded to correspondwith the U7N8 options of RE signal generator of HP ESG-D Series.Real-Time I/Q baseband signal generator can follow up closely and be changedwith the requirement of digital communication standard. It offers two flexible structuresof baseband. It combines the style of modulation with the symbol rate and filter togenerate the digital modulation signal. This universal characteristic gives flexibility offollowing the high speed of the development of digital communication standards. TheTDMA module can be tested by only one equipment. Real-Time IIQ baseband signalgenerator sustains DECT, GSM and PHS communication standards. Data that thesestandards use is created by internal or offered by external.This paper discusses the theories and the princples of generating IIQ basebandsignal of various digital communication systems in detail. On the basis of this, FSK,PSK and QAM modulation signals of several TDMA digital communication systemshave been designed and realized by using reconfigurable technology of FPGA andadvanced EDA tools. The paper gives the constellation maps that have been got bymeasuring with oscilloscope. Three types of FIR digital filters have been realized byusing FPGA and their parameters can be changed by setting the relebant parts ofsoftware. It contributes to developing RE signal generator that accords with TDMAdigital communication system standards by ourselves. With communication enterprisedeveloping rapidly, the generator will have widely applications.The paper introduces FPGA and reconfigurable technology in brief. It gives thestandard frame structures, symbol rate, filter types and its parameters and modulationtypes of the baseband signal of PHS , GSM , DECT digital communicationsystems. Finally, the paper presents some problems that require to be solved andresearched in future.