C-band Point Frequency Source

Microwave frequency source is needed for many communication, radar, electronic countermeasure, instrument, biomedicine projects and measurement applications. At the same time, its performance influences the whole capacity of a system directly. Stability of a frequency source is the key issue. Phase-locked loop is used, in which a short-term stability DRO combines with a long-term stability crystal oscillator, an output signal with high short-term and long-term stability is received ultimately. The dominating factor which influences the short-term stability is phase noise, that is stochastic frequency-modulated noise or phase-modulated noise. Improving short-term stability is interrelated with choice of devices and working state.Because of small bulk, high-Q, compactness, low cost and easily integration, dielectric resonator is becoming increasingly common over the entire microwave frequency range. As a strongpoint, dielectric resonator possesses two advantages, improving stability and reducing noise while maintaining its bulk fixedness, whenas metal cavity is not reachable. We adopt the means of phase-locked loop to design. At first, we theoretically analyze the working principles and the composes of phase-locked loop, then exhaustively discuss the design of dielectric resonator oscillator, low noise amplifier and power divider using EDA simulation software. On the base of the guide line, we adopt 100MHz crystal oscillator as the referenced source. The phase-locked loop is composed of ADF4106, VCO and LF. The phase noise and output power of measurement results are respectively-85 dBc/Hz@10kHz and 10 dBm. The dimension of the frequency souce is 79×80×20mm.The main contributions and creative points of this dissertation are as follows: (1) The low flicker noise transistor HBT, a common emitter configuration and a single de power supply are used. We analyze the theory of the varactor-tunable dielectric resonator oscillator. Design and optimization of the parallel feedback configuration are done using CST and ADS. (2) The low noise coefficient transistor FET, a common source configuration and a double electrical sources supplying power are used. Design and optimization of the single stage amplifer is done using ADS. (3) The simulation results and experimentation outcomes are compared and the reasons of resulting in windage are analyzed. The phase-locked dielectric resonator oscillator has the merits of simple configuration, high dependability, easy integration, small cubage, multifunction and etc.