The Differential Transform Domain Communication System Technology Research And Realization

Transform Domain Communication System(TDCS) modulate the wareform with channel information,it can resist diversified forms of interference effectively;TDCS make full use of idle spectrum without affect to other users,and solve the problem of spectrum resources shortage.With CCSK(Cyclic Code Shift Keying) modulation,TDCS take a base function which is similar to noise as the carrier of information,so it has high security. Due to the advantages mentioned above,TDCS has caused more and more concern in the general communication.In recent years,a lot of researches about TDCS have been done in domestic, however,there are few papers which are about the realization of it.In this paper,We will introduce the key technology of difference TDCS and realize it with Soft Defined Radio Development Platform(SDR DP) on the base of pre-researches. The main work of this paper can be divided into three parts:The first part introduce the structure of difference TDCS which is based on Orthogonal Frequency Division Multiplexing and simulate the performance of the system.The performance of two differential system are compared in AWGN(Additive White Gaussian noise) channel to select the appropriate implementations,in addition,we have discussed the effects of the raised cosine window to TDCS.The second part is about the implementation of TDCS.First of all,we disscuss the data port between DSP and FPGA.It indicate that VPBE can reach the highest rate of 12.8 Mbps under the condition that FPGA receive the continuous data stream and reach 64Mbps under the emergent mode.Secondly,we finished TDCS transceiver,receiver and FDD-TDCS(Frequency Division Duplexing) system on the SDR Develop Platform.In this step,we have solved many key problems and optimized the hardware resources of the system,finally the link of FDD-TDCS has consumed slice 53 percent of the SDR platform.The third part is about the performance test of difference TDCS,we have tested the power of SDR platform noise,the performamce of difference TDCS in the noise condition and the performamce of difference TDCS in the Jamming condition,and compared the result with simulation performance to improve our system.At last,we completed the demo system of TDCS anti-interference adaptively under the assistant of FH system.This paper provides implement scheme of TDCS which is based on OFDM technology with SDR platform and tested the performance of the system under the noise and jamming condition,and realize the reliable information transmission.This work have strong practical and reference value.on the other hand,it provided examples and experiences to researchers who work with SDR platform.