Ultra-Wideband Low-Noise Amplifier and Six-Port Transceiver for High Speed Data Transmission

Today’s data rates in wired networks can reach 100 Gbit/s using optical fiber while data rates in wireless networks are much lower tens of Mbit/s for 3G mobile communication and 480 Mbit/s for ultra-wideband (UWB) short range wireless communications. This difference in data rates can mainly be explained by the limited allowed frequency spectrum, the nature of the radio signal and the high requirements imposed on all hardware designed for high speed and wideband wireless communications. However, the demand on wireless commercial applications at competitive costs is growing. The first step in regulations allowing higher data rates for wireless communications was taken in 2002, when the Federal Communication Commission (FCC) in USA released unlicensed the 3.1-10.6 GHz frequency band restricting only the power level (maximum mean equivalent isotropic radiated power density of a UWB transmitter is -41.3 dBm/MHz) in the band 3.1-10.6 GHz. But Europe, Japan and recently China have put additional restrictions on the 3.1-4.8 GHz band. The restrictions address the problems that have raised from the coexistence and colocation of the UWB systems with other narrowband wireless systems. Thus, the 6-9 GHz band combined with an increased modulation order scheme is of large interest. Operating at higher frequency and wider bandwidth than today’s communication technologies, with the general task of maximizing the wireless data rate while keeping the power consumption low, requires new communication system solutions and new circuit design approaches. These new solutions also require understanding of many multi-disciplinary areas which until the recent past were not directly related: from classic analog circuit design to microwave design, from modulation techniques to radio system architecture. In this thesis, new design techniques for wide bandwidth circuits above 3 GHz are presented. After focusing on ultra-wideband low-noise amplifier (UWB