Low Phase Noise Millimeter-wave Point-frequency Source

For modern microwave and millimeter wave systems, the performance of the system mostly depends on the quality of the sources. Sources have many performance specifications, but the phase noise is one of the most important. The phase noise is in close relationship with the performance of system, for this reason, the low phase noise source is widely used in system to optimize its performance.In this dissertation, a low phase noise millimeter wave point frequency source is studied. The source works at Ka band, and consists of a dielectric resonator oscillator(DRO) and frequency multiplying circuit. A low noise DRO works at Ku band is designed, then, the output signal is multiplied to Ka band by the frequency multiplying circuit, which includes an amplifier, 3 filters, a frequency doubler and a microstrip-waveguide transition. The advantage of the plan is that the source has low phase noise, and is easy to realize, meanwhile, the cost is low.In this dissertation, the basic theory of low phase noise millimeter wave source based on DRO is described at first. The basic theory of signal generation, dielectric resonator oscillator, the couple model of dielectric resonator and microstrip line, the phase noise of source, the linear model of phase noise, amplifier and filter are briefly reviewed.The design proposal of low phase noise millimeter wave point frequency source based on DRO is presented. Then, the design of buffer amplifier, filters, frequency doubler and microstrip-waveguide transition are discussed in detail.The test results of the source indicate that the output frequency is 27.508GHz, the phase noise is -82dBc/Hz@10kHz offset, the output power is 10.11dBm. According to the analysis of these results, the suggestion of improvements in the future is put forward.