Research On The Key Technologies Of RF Module In Adaptive Interference Cancellation System

Along with the advancement of technology, wireless communication technology is more and more widely used in various fields in the society. The transmission of signals in wireless channel is getting more and more crowded, the mutual electromagnetic interference is more and more strong. It is especially stronger between tens of MHz and hundreds of MHz, channel absolute bandwidth is more narrow compared to microwave, but a large number of application of wireless communication is accomplished in this frequency band, which further exacerbates the mutual interference between the signal. It is an effective way to solve the problem of electromagnetic compatibility using adaptive interference and noise cancellation technique in frequency hopping communication, which has been fully proved in practice in the domestic and foreign interference cancellation device.This paper firstly introduces the adaptive interference cancellation system research background and significance, the overall summary of domestic and foreign research progress of adaptive interference cancellation system and adaptive interference cancellation system. Adaptive interference cancellation system is a concrete application of adaptive filter. The feasible analysis of application of stripline directional coupler in the frequency band under inclues three parts:first, to study the device miniaturization, by folding the strip line and using the unbalanced cross cascade way of reducing device size, by increasing the dielectric constant decreases with the electric length line, coupling degree control device to change the medium plate and two sides of the substrate thickness, the implementation feasibility through the simulation the authenticator pieces; Secondly, in-depth study of the device of phase balance, propose a solution of cross cascade stripline directional coupler phase balance, validated successfully solve the problem of high frequency phase shift; Finally, proposes a method to reduce the 1/4 wavelength stripline coupler input method, by using tapered line on two level 1/4 wavelength connecting mode to reduce the signal reflection and improve the device power capacity. And the improved scheme of future possible analysis, form design entirely using gradient line ultra broadband stripline coupler. Through the simulation of 0.7-2.7GHz ultra broadband stripline coupler to verify the above three points of view. By analysing the attenuator module circuit, designed and implemented an ultra wideband high power electric adjustable attenuator circuit, and have the real attenuation amplitude frequency characteristic and phase frequency characteristic analysis of test.