The Design and Analysis of Fully-Monolithic RF Coupled-Voltage-Controlled-Oscillator 1-Dimensional Arrays in 0.18µm SiGe BiCMOS

Vol.2 No.1

Year: 2008

Issue: Jul-Sep

Title: The Design and Analysis of Fully-Monolithic RF Coupled-Voltage-Controlled-Oscillator 1-Dimensional Arrays in 0.18µm SiGe BiCMOS   

Author Name: Jerry Lopez, Donald Lie , J. Cothern , Joseph Neff , Brain K. Meadow   

Synopsis:   

The analysis and design of integrated circuits (ICs) of fully monolithic 1-Dimensional (1-D) AC-coupled Voltage-Controlled-Oscillators (VCOs) networks useful for phase array antennas is presented. The fully-integrated RF VCO arrays integrate on-chip inductors, varactors, MOSFETs, BJTs, and biasing current sources and they each contain an odd number of VCOs AC-coupled through switchable resistor arrays. We designed, simulated and fabricated several these 1-D VCOx5 arrays in a production 0.18µm BiCMOS process (i.e., IBM 7HP). Our design can control the phasing of the on-chip VCO array by means of tuning the edge VCO elements and/or by varying the coupling strength via different resistor values. Circuit-level SPICE simulation shows promising results allowing phase and amplitude configurations across the array to offer high directivity and element-to-element phase tuning arrangement that can be achieved by simply manipulating the on-chip coupling network with edge VCOs tuning. Moreover, circuit simulation shows that some of these conditions allow a ~±20o coverage from broadside without the need for phase shifters. These AC-coupled 1-D VCO arrays, therefore, shows great potential for RF active antennas applications to perform wide angle beam steering for the highly used 1-2GHz S-band.