The Design and Implementation of Antenna and Power Amplifier for UWB Communications

• Main Authors: Chang-Ming Liu, 劉昌明
• Other Authors: Wu-shiung Feng
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/58010041543077910200

碩士 === 長庚大學 === 電子工程研究所 === 94 === Antennas and power amplifiers play critical roles in wireless transmitter systems. Antennas are terminal components of wireless transmitter systems that have impact on system transmission efficiency directly. Improving the outdated antenna structure in order to upgrade transmission efficiency is an important factor for antenna designers in recent years. Power amplifiers are the terminal stage of RF transmitter circuits. The main considerations for PA design are achieving high output power and high efficiency; the output power of PA is an important issue for the transmission distance, and the efficiency is proportion to the operation time of wireless equipments, respectively. Therefore, the influence of antennas and power amplifiers on overall system performance is self-evident. In this thesis, we propose two projects for ultra-wideband(UWB) applications: one is a wideband planar patch antenna, and the other is a wideband power amplifier fabricated by commercial CMOS process. With regard to the proposed antenna, the UWB property for the double-sided printed bow-tie antenna is achieved by using a new impedance-matching technique of adding symmetrical rectangle and elliptical structures on the ground plane. The experimental results show that the proposed antenna exhibits a nearly omnidirectional radiation pattern for a wide range of frequencies, a wide band impedance match (3.1GHz-10.6GHz) and flatness gain (2.1dB-2.52dB) under the UWB impedance bandwidth. As to the proposed power amplifier which is a two-stage design, fabricated by TSMC 0.18μm 1P6M CMOS technology. The input stage is a Class AB power amplifier for high efficiency, and the output stage is a Class D power amplifier for low power consumption. The proposed architecture of power amplifier proves that the benefits of low power consumption (35mW), flatness gain (10.3dB-7.0dB) and stable output power (11dBm) under the UWB high-frequency range (6GHz-10.6GHz).