毫米波段注入锁定同步带宽展宽技术研究

【作者】 游建良；

【导师】 唐小宏；

【作者基本信息】 电子科技大学 ， 电磁场与微波技术， 2006， 硕士

【摘要】 注入锁定技术具有稳频、放大、调制等特性,已被广泛应用于微波毫米波以及更高频段通信和相控阵系统中的小信号恢复、频率同步、功率合成、相位调制等。这种电路结构简单、成本低廉,但其可靠入锁与噪声抑制性能之间的矛盾影响了系统的稳定性和可靠性。本文旨在寻求合适的方案解决注入锁定存在的入锁可靠性难题,实现同步带宽的展宽,使其应用系统稳定可靠,同时结构简单、成本低廉。文章首先介绍了注入锁定同步带宽计算的不同方法,进行了优缺点的比较,并从分析模型的角度阐释了这些方法计算出的同步带宽的不同之处;然后对注入锁定同步带宽展宽技术展开了讨论,阐述了不同展宽技术的特点。在此基础上,结合注入锁定和环路锁相原理,在毫米波频率源中引入了一种新型的展宽带宽的电路结构――环路注入锁定锁相电路(ILPLL)。文章详尽分析了此电路在展宽带宽方面的特性和相噪的优越性,设计了Ka波段腔体结构形式的ILPLL电路并验证了其特性。由ILPLL电路特性的推导得出:注入锁定带宽不仅跟开环时的注锁带宽有关,而且与混频特性、环路增益以及环路相位变化相关联,可以通过调节环路的参数得到所需带宽;相噪特性主要由环路传输因子决定,可以通过调节环路滤波得到比开环注入锁定相噪更优的特性。经过实验验证,设计的Ka波段ILPLL电路的锁定带宽拓展了2.5倍以上,最大处达到9倍左右;相噪与开环注锁相比降低了4dBc@1KHz,且可以通过调节环路滤波和注入功率来降低噪声。本文特色在于成功地实现了Ka波段腔体结构ILPLL电路,大大拓展了注锁同步带宽,电路噪声得到优化,而且电路结构相对简单、成本较低廉,有较广泛的应用前景。更多还原

【Abstract】 The injection-locking technology, characterized by the frequency stabilization, amplification, modulation and etc, has been widely used in the small-signal recovery, frequency synchronization, power synthesis, phase modulation and etc in the microwave, millimeter wave and higher frequency range communication and phased-array systems. Though this kind of circuit has a simple structure and a low cost, the conflict between the reliability of locking and the noise reduction influences the stability and reliability of the system. The thesis aims at finding a proper proposal to solve the difficult issue regarding the reliability of locking and make the system become stable and reliable and in the meantime, simple-structured and low-cost.The paper firstly introduces the various calculation methods of injection-locking bandwidth, compares their merits and demerits and from the perspective of the model analysis illustrates the differences of the bandwidths calculated by these methods. On such a basis, the injection-locking range improvement technology is discussed and the features of various locking range improvement technologies are elaborated. And the new circuit structure for improving the locking range, that is, injection-locked phase-locked loop circuit (ILPLL) is introduced into the millimeter wave circuit. The paper analyzes in detail the characteristics of this circuit in the aspect of locking range improvement and its merits in the aspect of phase noise, and designs the ILPLL circuit in the form of Ka band cavity structure and verifies its characteristics. It can be deduced from the characteristics of ILPLL circuit that injection-locking bandwidth is not only related to the injection-locking bandwidth without feedback loop, but also related to the characteristics of frequency mixing, loop gain and the change of the loop phase. Thus, the needed bandwidth can be obtained by adjusting the loop parameters. And the phase noise characteristics are mainly determined by loop transmission factor. Thus, the better phase noise can be obtained by adjusting the loop wave filtering. Through experimental verification, the locking range of the designed Ka band ILPLL circuit is 2.5 times to 9 times widened and the phase noise, compared to that without feedback loop, is reduced by 4dBc@1KHz and the noise can be reduced by adjusting the loop wave filtering and更多还原