【導(dǎo)讀】近幾年隨著商用無線通信的迅猛發(fā)展，射頻/微波電路越來越得到重視和發(fā)展。而微波帶通濾波器作為微波器件的一種也得到了大力的發(fā)展，尤其是在接收機前端，帶通濾波器性能的優(yōu)劣直接影響到整個接收機性能的好壞。因此，發(fā)展高性能，研究小型化的微波濾波器是當(dāng)前非常受關(guān)注的課題。本文首先介紹了微波濾波器的發(fā)展歷史、在微波通信中的作用、當(dāng)前的研究情況以及微波仿真軟件ADS。然后分析了微帶濾波器的二端口網(wǎng)絡(luò)理論。最后該論文基于仿真軟件ADS和推導(dǎo)公式的基礎(chǔ)上，介紹了微帶線帶通濾波器的設(shè)計方法，同時借助ADS軟件對所設(shè)計的微帶線濾波器進(jìn)行了仿真和優(yōu)化，最終得到比較理想的微帶線濾波器，－，帶內(nèi)衰減小于2dB，起伏小于1dB，，端口反射系數(shù)小于-20dB。隨著現(xiàn)代材料科學(xué)與電子信息科學(xué)技術(shù)的交叉滲透和全面發(fā)展，全固態(tài)化的各類片式高頻、微波濾波器和中頻濾波器，向著高性能、低成本、小型化、高頻化等各方面

　　

【正文】 selocked loop, ADS also provides transientassisted harmonic balance (Transient Assistant HB) simulation methods, circuit analysis in the first implementation of the transient analysis, and this Transient analysis of the results of the analysis of harmonic balance, as the initial conditions for circuit simulation by this method can effectively solve the highly nonlinear circuit analysis will occur when the situation of nonconvergence. Analysis circuit (Circuit Envelope) Envelopment analysis circuit includes a timedomain and frequency domain analysis methods can be used in the circuit contains the FM signal or munications system. Envelopment analysis circuit from the SPICE simulation with the harmonic balance method has the advantage of two, will lower the frequency of the FM signal with timedomain SPICE simulation approach to the analysis, and a higher frequency of the carrier signal with frequencydomain simulation method of harmonic balance analysis RF System Analysis RF simulation analysis method of assessment systems to provide users with the characteristics of the circuit model in which the system can be used in addition to behavioral models, circuit ponents can also use the model to respond to conventional verification. Simulation Analysis of RF systems include the abovementioned linear analysis, harmonic balance analysis and circuit envelope analysis, were used to verify the passive ponents in RF systems and linear system model of the characteristics of the model characteristics of nonlinear systems with digital FM signal characteristics of the system. Analysis of delay Palamidi (Ptolemy) Palamidi delay analysis simulation at the same time can have a digital signal and analog, mixedmode highfrequency signals in the capacity of the system. ADS, respectively, the model provides a number of ponents (such as FIR filters, IIR filters, AND logic gate, OR logic gate, etc.), munications system ponents models (such as QAM demodulator FM, Raised Cosine filter, etc.) and simulation of highfrequency ponent model (such as IQ encoder Chebyshev filter, mixer, etc.) available. Analysis of the electromagnetic simulation (Momentum) ADS software offers a planar electromagnetic simulation analysis Momentum (ADS2005A version Momentum has been upgraded to a 3D electromagnetic simulator) can be used to simulation of microstrip line, stripline, coplanar waveguide, such as the electromagnetic properties, antenna radiation characteristics, as well as the parasitic circuit board, coupling effect. S parameters of the analysis results can be directly used in some wave balance and circuit envelope, such as circuit analysis, circuit design and verification. Analysis of the Momentum electromagnetic analysis model offers two: Momentum microwave mode that Momentum and Momentum RF mode that Momentum RF。 users can work in accordance with the circuit judge and sizeband, choose to use.Protel99Protel99 is Windows9X/2000/NT operating system used in the EDA design software, design database management model that can be network design, has a strong capacity and open data exchange and 3D simulation capabilities, is a 32bit design software , to be pleted schematic circuit design, printed circuit board design and the design of programmable logic devices, etc., can be designed 32 signal layers, power supply 16 and 16 stratigraphic layer machining. first. Protel 99 ponents of the system divided in accordance with the system, Protel99 most of the major include the following two and six function modules. of the circuit design (1) part of circuit design (Advanced Schematic 99): part of the circuit design including schematic circuit diagram editor (the editor SCH), circuit parts library editor (the editor Schlib) and a variety of text editor. The primary function of the system are: drawing, modify and edit the circuit schematic diagram。 update and modify the circuit parts library。 view and edit parts of the circuit and the various statements of the Treasury. (2) printed circuit board design system (Advanced PCB 99): printed circuit board design system, including the editor printed circuit board (the PCB Editor), spare parts package editor (the editor PCBLib) and circuit board ponents Manager . The primary function of the system are: drawing, modify and edit the circuit board。 update and modify the package ponents。 management of circuit board ponents. (3) automatic routing system (Advanced Route 99): Based on the system contains a shape (Shapebased) automatic gridfree routing, for automatic printed circuit board wiring, in order to achieve the automation of PCB design. simulation and PLD in part (1) Circuit Simulation System (Advanced SIM 99): circuit simulation system includes a digital / analog signal simulator that provides a continuous digital signal and analog signals in order to signal to the circuit schematic simulation, in order to verify the correctness and feasibility. (2) programmable logic design system (Advanced PLD 99): programmable logic design system that contains a grammatical function in a text editor and a waveform editor (Waveform). The primary function of the system is。 an analysis of the logic circuit, integrated。 observation of the waveform signal. Maximize the use of PLD system can streamline the logic of the ponents, so that the number of simplifying the circuit design to achieve the best. (3) High signal integrity analysis system (Advanced Integrity 99): signal integrity analysis system provides an accurate signal integrity simulator that can be used to analyze the PCB design, circuit design parameters to check the experimental overshoot, impedance and signal harmonic requirements. Second, Protel 99 The functional properties 1, openended design of integrated management system 2, superfunction, modify and edit function 33a powerful design automation.