Dual-band High Efficiency All-digital Transmitters

With the rapid development of information technology in recent years,the number of users of communication equipment keeps increasing,and the demand of communication business also becomes diversified,which puts forward higher requirements for the development of communication system.There are more and more transmission signal standards and modes,and the transmission frequency band keeps increasing,and the peak-to-average power ratio(PAPR)of the transmitted signal is also getting higher.In order to meet the needs of different communication scenarios,the physical layer of the communication system must be able to support the efficient simultaneous transmission of multi-frequency,multi-mode and multi-standard signals.However,in order to realize signal transmission between multiple frequency bands,traditional wireless analog communication system needs to design circuit boards for different frequency bands,which leads to the increase of equipment area and cost,and it is difficult to achieve flexible frequency conversion,poor reconfiguration and poor system efficiency.Therefore,it is of great significance to study and design a dual-band high-efficiency all-digital transmitters to satisfy the simultaneous transmission of multiple frequency band signals and improve the overall efficiency of the system.This paper takes this as the focus of research,and its main work is as follows:Firstly,the architecture of the existing Delta-Sigma modulator is introduced and analyzed,and a Delta-Sigma modulator that can simultaneously transmit dual-band signals is designed and optimized.In addition,on the basis of the multi-core delta-sigma modulator,a dual-band multi-core delta-sigma modulator based on the predictor is proposed to further reduce the impulse noise caused by the discontinuity between the data,which provides a design basis for the key modules of the all-digital transmitters.Secondly,a dual-band all-digital transmitter based on Delta-Sigma modulation is designed.The system can simultaneously transmit independent and controllable dual-band signals,and the transmission signals are not restricted by the signal standard and standard.At the same time,the design of multiphase interpolation filter,multiphase digital up-conversion and other modules,and the whole digital transmitter system link MATLAB simulation.The operating frequency of the whole digital transmitter system reaches 10 GHz,and any adjustable carrier frequency range is 0?5GHz.Thirdly,a dual-band all-digital transmitter based on outphasing architecture is designed to provide digital realization for the high-efficiency outphasing power amplifier transmitter architecture.Combined with the hardware implementation characteristics,the design and optimization of signal separation,multiphase modulation and other modules,and in MATLAB to carry out the full digital RF link simulation.Fourthly,the design scheme of two dual-band all-digital transmitters designed in this paper is implemented and tested on FPGA platform.The hardware description language Verilog is used to write and debug the whole data link processing of the all-digital transmitter respectively.After digital signal processing,baseband signals are output by the high-speed interface on the FPGA development board,and then tested on the instrument to verify the feasibility of the design.