High-resolution vector-sum phase shifters for X-band phased arrays in SiGe BiCMOS

Official URL: http://risc01.sabanciuniv.edu/record=b1640325 (Table of Contents)

The market for phased arrays are limited due to the cost, size, power consumption and complexity of the traditional transmit/receive modules that are implemented with III-V technologies. The spread of next-generation phased arrays in modern commercial and military applications is only possible by adressing the discussed cost and technical issues. Thus, next-generation phased-array systems plan to use lowcost and fully integrated transmit/receive modules. Considering the high frequency performance and its integration capability with CMOS devices, SiGe BiCMOS technology is an excellent candidate for this purpose. The main goal of this thesis is to develop integrated electronic phase shifters, the most essential elements in phased arrays, in a commercial SiGe BiCMOS technology for X-band while maintaining high performance with low cost. When being implemented on a silicon substrate, electronic phase shifters often become a problematic building block for transmit/receive modules. Conventional electronic phase shifter designs which are built by using only passive elements in III-V technologies can achieve low insertion-loss values due to high-quality passive components and high-isolation substrate. However, the conductive substrate of the silicon technologies that causes signi cant losses for passive components and transistors results in phase shifter designs with high insertion-loss values. Thus, there is a complex trade-o between gain, power consumption, linearity and noise gure of integrated electronic phase shifter designs implemented with silicon technologies. Fundamentals and working principles of di erent electronic phase shifter topologies are covered with a comparative analysis in this thesis. It is shown that, in order to achieve a wideband high phase resolution in a small chip area, vector-sum phase shifter topology is the best solution. Trade-o s between di erent phase shifter performance parameters and di erent vector-sum phase shifter building block topologies are studied and the measurement, simulation results of the implemented vector-sum phase shifter designs are presented.