The Design and Implement of Low Noise Amplifier for DCS 1800 System

• Main Authors: Fan-Si Kong, 孔繁喜
• Other Authors: Man-Long Her
• Format: Others
• Language: zh-TW
• Published: 1999
• Online Access: http://ndltd.ncl.edu.tw/handle/67049038852742763562

碩士 === 逢甲大學 === 電機工程學系 === 87 === The purpose of our paper is to design and implement a 1.8 GHz band low noise amplifier for DCS 1800 system. Its operation frequency is from 1710 MHz to 1785 MHz. In order to have low noise figure, good input return loss, and low voltage standing wave ratio, we will compare the advantages and disadvantages of five circuit topologies that can yield simultaneous noise and power matching. Considering the specification and operation frequency of our circuit, the circuit topology of cascode inductor series feedback (CCSF) will be used to implement our low noise amplifier (LNA). Our LNA circuit has been achieved with the association gain more than 22 dB, the input/output return loss less than -10 dB, the noise figure less than 2.0 dB, and the 1dB compression point about -3.2 dBm. Because the characteristics of the active and passive component are very important for the microwave circuit design, we thus propose a technique to model the passive components. Furthermore, we will discuss the Gummel-Poon DC model of a BJT. We will also show the test results for the LNA’s built in MMIC (monolithic microwave integrated circuit).