The Study And Implementation Of Wide-band Matching Networks Theory--The Research Of 500MHz～2800MHz Wide-band Amplifier

Matching problem is an essential issue in RF communication, while the construction of wide-band matching network (WBMN) is the diamond on the crown. In this thesis, the theory of WBMN and an engineering design are proposed.Firstly, the basic knowledge of network is introduced and several theories in WBMN are brought forward. Based on this issue, several methods of WBMN design in communication network are brought up and some conclusions of practical application were concluded. Secondly, a wide-band amplifier working on the band of 500MHz~2800MHz was designed, which performs perfectly under a newly created method on WBMN. The following are the main works of this thesis:(1) Some conclusions are made on the procedure of the construction of BWNM under traditional design method of impendence synthesis.(2) Some defects in traditional design method are indicated, the optimization of BWNM is detailed. The procedure of construction of BWNM under optimizing method is also detailed.(3) The principium of S parameter analysis of transistor amplifier are discussed, some improvement strategies are concluded.(4) A new simple WB microwave active bias structure is brought up which effectively reduces the effect on microwave device by bias. Compared to traditional bias circuit structure, it has some advantages including suppleness in structure and realization.(5) Combining the real frequency method with direct optimization method, a WBNM synthesis method with high performance is proposed. Its innovation lies in the denotation of the complex weight coefficient in an area on the Smith's Chart. Based on this method, several WB matching networks under different condition are synthesized.(6) In the design of microwave circuit, more than one weight conditions are need. One method for creating the initiate weights is discussed in this thesis, based on the method brought up, the optimization efficiency is improved consumedly.(7) A WB amplifier working at 500 MHz~2800 MHz is designed, the performance answers for the previous target. The amplifier is adopted in a project in the Shanghai Space Flight T.T&C and Telecommunication Institute.