In recent, ultra-wideband systems have been presented as an emerging solution to wireless communication applications requiring high data rates over short distances. The purpose of UWB systems is to provide a specification for a low-cost, low complexity, low power, and high data rate wireless connectivity among devices within personal area. Although the characteristics of the UWB system have been widely reported, there are still many challenging issues which muse be improved. Especially, the design of low power transceiver is one of the important problems in battery-powered portable device applications and wide-bandwidth characteristic more than 7.5 GHz is also challenging issues in UWB system design.
This thesis concentrates on the design and implementation of power reduction and wideband receiver front-end for UWB applications. The focus is on the solution of challenging issues; a low power design, an ultra-wide bandwidth, a fast frequency hopping design, and a linearity issue of UWB receiver.
At first, UWB direct-conversion architecture is proposed with considering the DC offset canceling technique, single-to-differential conversion, and improvement of receiver linearity. Additionally, sub-band generator architecture for fast frequency hopping is presented and summarized the spur characteristics in all frequency bands using this topology. According to the receiver architecture the link budget of UWB system is presented. In addition, several receiver specifications such as noise figure, linearity, dynamic range, low pass filter, and phase noise of LO signal are proposed. And then, each stage specification of receiver is suggested.
Next, an UWB RF receiver front-end IC has been presented. This chip consists of the LNA with interferer rejection, the down-conversion mixer, and the low pass filter. The proposed LNA utilizes a common-gate topology with active notch filter. The maximum gain of 13.3 dB and the minimum noise figure of 5.2 dB are achieved with in...