The New Magnetic Dielectric Substrate Microstrip Antenna In Applied Research

Firstly, this paper introduces the requirement of electronic equipment antennas in national economy and defense construction modernization, which is characterized by miniaturization, portabilily, broadband and conformality, combined with the typical rectangular microstrip patch antenna on the dielectric substrate. The paper analyses the antenna's radiation rationale and designing method, and deeply discusses the characteristics and influence factors of the microstrip antenna. It is suggested to use a new type magnetic medium substrate(μr,εr) to improve the the characteristics of the microstrip antenna. Then, the general form and realization method of the circular polarization microstrip antenna is discussed. The theory and design of the circular polarization rectangular microstrip antenna is introduced specially for engineering design.For using the new polymer magnetic medium substrate to design and make the microstrip antenna, a detailed discussion is conducted about the relation between effective parameters (μe,εe) and relative parameters(μr,εr) of the magnetic medium substrate, and a useful analytical expression is got by the electromagnetic duality. The mutual influence between u r andεr is found based on a deep analysis, and consequently the measuring accuracy of u r andεr does not satisfy engineering design requirements. The paper brings up a synthetic method which is able to accurately determine Ur andεr, and emphasizes on the principle, implementing scheme, synthesis procedure and experimental verification of the method, to lay a necessary foundation for the application of the new magnetic medium substrate in the design of the microstrip antenna.At last, some antennas have been designed and made with the new magnetic medium substrate, inluding small-sized left and right circularly polarized microstrip antennas for the GPS system, missile-borne surrounding conformal microstrip antennas and small-sized broadband mobile phone antennas. It is demonstrated by the measurement results that the measuring accuracy ofμr andεr is able to completely satisfy engineering design requirements on the basis of the synthetic method in this paper. The results fully show the broad application prospect of the new magnetic medium substrate.