| The modern communication system’s unit part is the modulation and demodulation system, with the rise of the digital modulation system, which in the digital communication system is digital baseband modulation and demodulation technology. The modulation technology of the fourth generation mobile communication system is based on the OFDM technology. OFDM modulation system has variety advantages such as high trans- mission rate, high utilization rate of frequency band, anti falls ability and resistance to intersymbol interference. Bur the shortcomings of OFDM system gradually exposed: the rectangular window out of band fade is very slow, the inter carrier interference is significant under the influence of frequency offset and the cyclic prefix result in low spectrum efficiency, etc. With the imminent development of a new generation mobile communication system, we urgent need a new modulation technology to solve these problems.Bank Multi Carrier Filter(FBMC) technology is considered as the fifth generation mobile communication system alternative modulation method, raise more and more concern. Its anti ICI ablity is very good which can well solve the sub-carrier orthogonality need of OFDM system. It does not need use the CP to against the ISI, which makes the spectrum efficiency improved significantly. And With the combination of offset quadrature amplitude modulation(OQAM) makes adjacent sub carrier interference decline further. This thesis mainly research FBMC technique and implementation。Firstly the thesis introduced the basic principle of multicarrier system, and lead to the principle of OFDM modulation and FBMC modulation and their respective characte- ristics are introduced. On this basis, introduces the basic principle of FBMC modulation, and the characteristics of the prototype filter and design requirements and its difficulty.FBMC system the first difficulty lies in its hardware realization problem, due to the complexity of the modulation scheme, computing a substantial increase in the relative amount of OFDM systems, in order to solve this problem, the system realization structure were studied in detail in this thsis, and put forward a hardware implementation structure which is close to the calculation amount of the OFDM modulation system,which is polyphase network structure. The other difficulty is can not completely eliminate the adjacent sub carrier interference. Academic circles at present use OQAM modulation to avoid the interference of adjacent subcarriers.On this basis, this thsis analyzes the sub carrier interference of FBMC system and introduces the principle of OQAM modulation and the advantages of this technology combin with FBMC. Although OQAM modulation solved the FBMC system subcarrier interference problems, but it brings pilot algorithm and equalizer design a great challenge.This thsis put forward two kinds of pilot algorithm design schemes-- auxiliary pilot algorithm method and the adjacent carrier nulling method. The former method needs additional complexity and memory resources to complete the auxiliary pilot calculate, and the latter will consume a certain spectrum resources. In this thsis, two kinds of schemes were implemented with detailed analysis of simulation. But the design of the equalizer is not directly related to the modulation scheme, this thsis dosen’t discussed in detail.This thesis Simulate and critically analyze the fbmc system performance, in anti noise, frequency offset, timing offset ability and compared with OFDM system, And conclusion that the FBMC system is better than the OFDM system in the countermeasure against the above channel interference, and then analyzes the spectrum efficiency and the computational complexity of the FBMC system, and makes a quantitative comparison with the OFDM system.Finally, the hardware implementation of the FBMC simulation system structure analysis in the stupid Xilinx company K7 series XC7K325 T chip, given the resource consumption situation and implementation of error rate analysis. |
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