L-band Low Phase Noise 30w Ask Phase-locked Frequency-hopping Source Development

Frequency synthesis is the key technology of the radar and communication systems to get high-performance indicators. In order to achieve functions, many modern electronic devices and systems directly depend on the performance of the frequency synthesizer. Therefore, the design of the high-performance frequency synthesizer is an important research of the modern communication technologies.This article mainly introduces the scheme of designing an L-Band low phase noise hopping frequency synthesizer by using the principle of phase-lock-loop. Then according to the principle of ASK modulation and the design of power amplifier, a scheme of designing an ASK modulation and a power amplifier system is made, in order to achieve 30W power output.This article firstly describes the development of the frequency synthesis, and then introduces the working principle and basic parts of the PLL and the design method of the frequency synthesizer, gives the theory model of calculating the phase noise and spur. In the following, this article introduces the design theory of the modulation principle and power amplifier.In the last two chapters of this article, the design examples of an L-Band hopping frequency synthesizer based on STW81101 and an ASK modulation power amplification system are given. Then the phase noise, spur of the frequency synthesizer and the output power of the modulation power amplification system are tested. The result is satisfied and possesses some engineering significance.