The Research Of Some Key Technologies And Applications In Miniature Millimeter-wave Fuze

The demand of miniature and low power consumption fuze is becoming urgently as the development of precision guidance weapon system in recent years. The dimension of fuze is restricted severely in missile bore weapon system; the operating frequency has been expanded to millimeter wave and submillimeter wave frequency band for dimension and weight diminishing. Some kinds of miniature millimeter wave fuzes have been researched and equipped in some foreign countries, and submillimeter wave fuze is under research, some related research projects are also commenced in our country. On the other hand, the complexity and power consumption of weapon systems are becoming larger and larger. Power consumption becomes an important aspect for the restriction of battery capacity. To reduce the gross power consumption of the entire fuze system, multifunctional circuit theory must be introduced into the design process of fuze front-end, low power consumption millimeter wave fuze related research works have been developed in foreign countries and some new products have emerged, the related research works are just at preliminary stage in our country.This thesis aims at the related difficulties and technologies in design of low power consumption miniature millimeter wave fuze, some research works are done and several useful conclusions are acquired. The main research works are as follows:1. Millimeter wave passive circuit: Some different kinds of transmission line are analyzed according to their electromagnetic field distribution, some methods which are used for suppressing higher modes in CPWG (conductor backed coplanar waveguide) are researched and then a new kind of balun which is composed of CPWG and slotline is analyzed and validated.2. Millimeter wave frequency multiplier: The new kind of balun which based on the transition between shielded conductor-backed coplanar wave guide and slotline is used to acquire millimeter wave signal with simple and compact circuit. Millimeter wave frequency doubler is realized with a pair of diode and the above balun ultimately. The related theory of frequency doubler is analyzed firstly and then the millimeter wave frequency doubler is validated with experiment results.3. Transmission line transition: The traditional transmission lines such as coaxial line are no longer suitable for using as transition structure between antenna and front-end circuit in millimeter wave multilayer circuits for its huge transmission line loss in millimeter wave frequency band, so coupled structures must be introduced into transition design. On the other hand, high performance flexible transition structures between circuit and circuit or circuit and antenna in different layers are needed urgently as increasing of system complexity and system dimension restriction. Aperture coupling or substrate integrated rectangular cavity coupling structure is usually used in traditional multilayer millimeter wave circuits. However, the electromagnetic field distribution of substrate integrated rectangular cavity is non-revolution-invariant; flexibility of the transition structure is limited by this disadvantage. This thesis introduced SICC (substrate integrated circular cavity) into transition structure firstly, and some kinds of transition and transition-power divider structures are proposed. These structures are characterized with high flexibility and can be realized easily in multilayer microwave and millimeter wave module such as LTCC module. The restriction for outstretched direction of transmission line in traditional transition structure is overcome.4. Millimeter wave antenna: A series of antennas are researched and designed for different kinds of missile and different application situation. Linear polarization antennas include quasi-travelling wave comb antenna and angle-existing pencil-like pattern array; circular polarization antennas include single feeding wide axial ratio band antenna and dual-circular polarization antenna.5. Miniature millimeter wave fuze with circular polarization antenna: Linear polarization antennas are usually used in traditional dual-antenna topological structure fuzes for the axial ratio band of circular polarization antenna is usually very narrow. However the transmitter-receiver isolation of these systems is usually unacceptable in some times for the inherent disadvantages of linear polarization antenna. On the other hand, although some kinds of fuzes can be realized with a single linear polarization antenna, however, a T/R controlling device such as circulator or switch must be used in these systems. The power consumption and dimension of the overall system will increase for using of these devices. A novel kind of millimeter wave FMCW fuze system which uses wide axial ratio band circular polarization antenna as transmitting and receiving antenna is proposed in this thesis, the transmitter-receiver isolation of the system is improved without using of T/R controlling device. The theory of operation is analyzed and the feasibility is validated by measurement results, the fuze system is characterized with high efficiency and compact size.