Design Of Multi-channel Microwave Synthesizer

Microwave frequency synthesizer is one of the key components of today’s modern electronic systems, that many modern electronic systems performance directly depend on the indicators of microwave synthesizer。Therefore, the design of high-performance microwave frequency synthesizer is an important research direction.In this paper, the source of the subject is a radar transceiver module system project. We need to design multi-channel microwave frequency synthesizer to meet the needs of multi-channel LO signals from transceiver modules. The multi-channel microwave frequency synthesizer conprises of two parts, one of them is the multi-channel phase-locked frequency synthesizer, and the other one is the high-speed frequency hopping synthesizer based on DDS. Multi-channel phase-locked frequency synthesizer comprises more than 20 phase-locked loops, the point frequency outputs are controlled by the switch circuit. The lowest output frequency is 2GHz, and the highest output frequency is 12.4GHz. High-speed frequency hopping synthesizer adopts the DDS and PLL mixed frequency synthesizer scheme, which contains four output frequency signals of C-band.Firstly, paper gives out an overview of the frequency synthesizer technology and describes the status of the frequency synthesizer development, describes the theoretical knowledge of frequency synthesis technology which this paper involved, including the PLL and DDS circuit structures, indicators and analysis.Then, paper elaborates each design process of the multi-channel phase-locked frequency synthesizer,includes devices planning, the simulation of loop filter, MCU control module, power module and switching control module.The high-speed frequency hopping synthesizer achieves by DDS and PLL mixing scheme. The design of DDS module, frequency multiplication module, local oscillator module and mixer output module are elaborated in detail.Finally, we give out the view of circuits and the test results of the multi-channel phase-locked frequency synthesizer and high-speed PLL frequency hopping synthesizer.The test results meet the expected targets.