Hardware Design Of Spectrum Analysis And Phase Difference Measurement Equipment Based On Zero-IF

With the rapid development of radio technology,more and more radio equipment is widely used,therefore more and more wireless communication equipment will occupy more spectrum resources and aggravate the electromagnetic interference between signals.In order to ensure that wireless communication can be carried out normally,some modern communication devices also require the ability to monitor and analyze the communication spectrum in addition to meeting its own functional requirements.Using traditional desktop spectrum measurement equipment,the volume is slightly larger and the power consumption is higher.It is too wasteful to make a desktop spectrum measurement as a spectrum measurement module of a wireless communication device.Therefore,a low-power consumption,small size and scalable spectrum monitoring module is useful and marketable,which can meet requirements of some communication equipment.On the basis of spectrum measurement,the function of phase difference measurement is added.Phase difference is an important indicator to characterize the relationship between two signals.some parameters can be measured indirectly by measuring the phase difference,such as the frequency of the signal and the phase relationship of the input and output signals.The main research contents of this article are as follows:1.Firstly,we need determine the overall design plan according to the demand indicators,and make analysis on the design plans of each part of the overall plan.After analysis and demonstration,the receiver with zero-IF architecture is used as the RF front-end,and FPGA(field programmable gate array)is used as the baseband processor,and CPXI(Compact Peripheral Component Interconnect)is used as the data communication interface.2.According to the determined overall design plan,we can design and analyze the hardware circuit of the device.The main circuit design includes the radio frequency receiving unit circuit,FPGA and ARM control unit circuit,clock circuit,CPCI interface circuit and power supply circuit and so on.According to the CPCI bus specification,a standard 6U board is designed.3.We need analyze and design the hardware logic implementation of the device,and complete the relevant logic implementation within the FPGA.The main design logic includes the FFT(Fast Fourier Transform)algorithm for spectrum analysis,the Cordic(coordinate rotation digital calculation method)algorithm for phase angle calculation,and the CPCI data communication interface logic design for communication with the host computer.In addition,the configuration process and methods of the RF front-end are also analyzed and explained.Finally,by building a hardware test platform to verify and test the relevant parameter indicators.According to the test results to verify the feasibility and rationality of the subject's design scheme.In summary,the main research goal of this topic is to achieve spectrum analysis and phase difference measurement through a receiver with a zero-IF architecture.The spectrum analysis signal frequency can be up to 6GHz,and the maximum measurement bandwidth is 50MHz.The measurement range of the phase difference can cover-180~°~180~°,and we can test two signals at the same time.The equipment completed in this project has the advantages of small size,light weight,low power consumption,and strong scalability.