Abstract
The purpose of this work is to use a standard CMOS process to research and implement the solutions of monolithic and low cost RF front-end integrated circuits. The first chapter is an introduction, and the content of this thesis is divided into two parts. The first part is chapter 2 and 3, in which the device level is presented. Chapter 4 and 5 is the second part and the circuit and system level is presented. Finally, chapter 6 is the conclusion and future work. The theory and parameters of monolithic inductor are introduced and derived in chapter 2 and the structure of our proposed improved multilevel-shunting (IMS) spiral inductor is presented. It not only improves the quality factor, Q (15%) but also improves the self-resonant frequency, fSR (25%) greatly. Moreover, the configurable and adaptive ability to make it applicable to any specification, therefore the optimization can be done and the high competition is achieved. Besides, we expand it to symmetric configurations for the differential circuit applications, and the structure of our proposed further improved multilevel-shunting (FIMS) symmetric spiral inductor is presented. There is up to 46% improvement in fSR and without deteriorating the Q compared to the conventional multilevel-shunting (MS) spiral inductor with almost the same inductance, thus the configurable and optimal range is extended. By virtue of leading to a higher L/C ratio, the power consumption and characteristic of the circuit can be improved. Furthermore, it saves 25% area occupied compared to two asymmetric inductors. For the large inductance applications, the miniature 3-D inductor is a good choice. For the differential circuits, the structure and idea of miniature 3-D symmetric inductor are presented. The theory and parameters of monolithic transformer are introduced and derived in chapter 3. By way of the idea of IMS structure in chapter 2, we can use it in conventional interleaved transformers to adjust their pass and reject band with almost the same inductance of primary and secondary coils, therefore also having the configurable ability. In order to further reduce the cost, we present the miniature 3-D transformer. Due to its symmetric configuration, it is very suitable to replace two asymmetric inductors in differential circuit. Moreover, it saves about 70% area compared to the conventional planar transformer, and has wider available bandwidth and higher self-resonant frequency compared to the conventional stacked transformer. The evolution of dual-band receiver and the concurrent dual-band receiver we used are introduced in chapter 4. The concurrent dual-band low noise amplifier and novel notch filter for improving noise figure and image-reject ratio are implemented and measured. It achieves the less insertion loss in 2.4-GHz and 5.3-GHz band compared to conventional LC parallel resonant network and the depth of image (3.4-GHz) rejection improves over 12dB. Therefore, it is very suitable in concurrent dual-band receiver for RF image-rejection to overcome the image-reject ratio degrading due to gain and phase imbalances in down-conversion and baseband parts. The LC tank voltage-controlled oscillator is presented in chapter 5. By switching the inductor and varactor simultaneously, the dual center frequencies are achieved. Therefore, the dual-band VCO can overcome the problem resulted from the tuning range of varactor is limited as the process progress and supply voltage scaled down. The results are summarized in chapter 6 and we expound the goal and effect of low cost and high competition, and the future work.