Research On Multi-band Frequency Source Based On MIPS

With the development of radio,people continue to in-depth research on frequency sources,and research is not limited to single-structure frequency sources.Compared with the phase-locked loop,the hybrid frequency source has high flexibility and can cope with complex application scenarios.This article uses dual PLL technology to achieve multi-band output through mixing.The output frequency of the hybrid frequency source is higher than that of the DDS,and the output step is smaller than that of the PLL.The dual phase-locked loop mixing PLL can achieve both wide-band output and small stepping.Compared with the PLL fractional frequency division,the in-band spurs generated by the phase truncation are smaller.The MIPS architecture processor is good at network data transmission and data processing.The processor with MIPS core not only meets the requirements of low power consumption,super computing power and control ability,but also compatible with most of the current general peripheral devices for developers to use.The Open WRT operating system has support for MIPS architecture processors.It can quickly realize the sample of network integration equipment software and exchange data with general-purpose computers.At the same time,the cross-platform QT software integrated development environment makes software development complete and simple.This article briefly introduces the basic structure of the frequency source(phase detector,low-pass filter,voltage-controlled oscillator,mixer,etc.),and analyzes the transfer function of the phase-locked loop,focusing on the output of the phase-locked loop noise.On the basis of the above analysis,a frequency synthesizer based on MIPS dual phase-locked loop mixing is finally realized.The research of this paper is mainly divided into the following three parts:(1)Frequency source module design and physical debugging analysis.(2).Comprehensive design and physical debugging analysis of power supply module and MIPS core processor control module.(3).A computer software of QT platform compiling and each communication interface driver design and debugging analysis.The main power supply of the control system adopts 15 V power supply to provide different levels of working voltage for the radio frequency module and control board.The output frequency range of the frequency source is 100MHz?12GHz,and the frequency resolution is better than 100 MHz.The output frequency is composed of four frequency bands: 100MHz?2GHz,2GHz?4GHz,4GHz?8GHz,8GHz?12GHz,and each frequency band is realized by radio frequency switch.The maximum output power is 11 d Bm,the maximum spurious suppression is 63 d Bc,and the optimal phase noise is 91 d Bc/Hz@10kHz.