Design methods for 60GHz beamformers in CMOS

The 60GHz band is promising for applications such as high-speed short-range wireless personal-area network (WPAN), real-time video streaming at rates of several-Gbps, automotive radar, and mm-Wave imaging, since it provides a large amount of bandwidth that can freely (i.e. without a license) be used worldwide. However, transceivers at 60GHz pose several additional challenges over microwave transceivers. In addition to the circuit design challenges of implementing high performance 60GHz RF circuits in mainstream CMOS technology, the path loss at 60GHz is significantly higher than at microwave frequencies because of the smaller size of isotropic antennas. This can be overcome by using phased array technology. This thesis studies the new concepts and design techniques that can be used for 60GHz phased array systems. It starts with an overview of various applications at mm-wave frequencies, such as multi-Gbps radio at 60GHz, automotive radar and millimeter-wave imaging. System considerations of mm-wave receivers and transmitters are discussed, followed by the selection of a CMOS technology to implement millimeter-wave (60GHz) systems. The link budget of a 60GHz WPAN is analyzed, which leads to the introduction of phased array techniques to improve system performance. Different phased array architectures are studied and compared. The system requirements of phase shifters are discussed. Several types of conventional RF phase shifters are reviewed. A 60GHz 4-bit passive phase shifter is designed and implemented in a 65nm CMOS technology. Measurement results are presented and compared to published prior art. A 60GHz 4-bit active phase shifter is designed and integrated with low noise amplifier and combiner for a phased array receiver. This is implemented in a 65nm CMOS technology, and the measurement results are presented. The design of a 60GHz 4-bit active phase shifter and its integration with power amplifier is also presented for a phased array transmitter. This is implemented in a 65nm CMOS technology. The measurement results are also presented and compared to reported prior art. The integration of a 60GHz CMOS amplifier and an antenna in a printed circuit-board (PCB) package is investigated. Experimental results are presented and discussed

The Future of High Frequency Circuit Design

The cut-off wavelengths of integrated silicon transistors have exceeded the die sizes of the chips being fabricated with them. Combined with the ability to integrate billions of transistors on the same die, this size-wavelength cross-over has produced a unique opportunity for a completely new class of holistic circuit design combining electromagnetics, device physics, circuits, and communication system theory in one place. In this paper, we discuss some of these opportunities and their associated challenges in greater detail and provide a few of examples of how they can be used in practice

A Millimeter-Wave Coexistent RFIC Receiver Architecture in 0.18-µm SiGe BiCMOS for Radar and Communication Systems

Innovative circuit architectures and techniques to enhance the performance of several key BiCMOS RFIC building blocks applied in radar and wireless communication systems operating at the millimeter-wave frequencies are addressed in this dissertation. The former encapsulates the development of an advanced, low-cost and miniature millimeter-wave coexistent current mode direct conversion receiver for short-range, high-resolution radar and high data rate communication systems. A new class of broadband low power consumption active balun-LNA consisting of two common emitters amplifiers mutually coupled thru an AC stacked transformer for power saving and gain boosting. The active balun-LNA exhibits new high linearity technique using a constant gm cell transconductance independent of input-outputs variations based on equal emitters’ area ratios. A novel multi-stages active balun-LNA with innovative technique to mitigate amplitude and phase imbalances is proposed. The new multi-stages balun-LNA technique consists of distributed feed-forward averaging recycles correction for amplitude and phase errors and is insensitive to unequal paths parasitic from input to outputs. The distributed averaging recycles correction technique resolves the amplitude and phase errors residuals in a multi-iterative process. The new multi-stages balun-LNA averaging correction technique is frequency independent and can perform amplitude and phase calibrations without relying on passive lumped elements for compensation. The multi-stage balun-LNA exhibits excellent performance from 10 to 50 GHz with amplitude and phase mismatches less than 0.7 dB and 2.86º, respectively. Furthermore, the new multi-stages balun-LNA operates in current mode and shows high linearity with low power consumption. The unique balun-LNA design can operates well into mm-wave regions and is an integral block of the mm-wave radar and communication systems. The integration of several RFIC blocks constitutes the broadband millimeter-wave coexistent current mode direct conversion receiver architecture operating from 22- 44 GHz. The system and architectural level analysis provide a unique understanding into the receiver characteristics and design trade-offs. The RF front-end is based on the broadband multi-stages active balun-LNA coupled into a fully balanced passive mixer with an all-pass in-phase/quadrature phase generator. The trans-impedance amplifier converts the input signal current into a voltage gain at the outputs. Simultaneously, the high power input signal current is channelized into an anti-aliasing filter with 20 dB rejection for out of band interferers. In addition, the dissertation demonstrates a wide dynamic range system with small die area, cost effective and very low power consumption

A Millimeter-Wave Coexistent RFIC Receiver Architecture in 0.18-µm SiGe BiCMOS for Radar and Communication Systems

Innovative circuit architectures and techniques to enhance the performance of several key BiCMOS RFIC building blocks applied in radar and wireless communication systems operating at the millimeter-wave frequencies are addressed in this dissertation. The former encapsulates the development of an advanced, low-cost and miniature millimeter-wave coexistent current mode direct conversion receiver for short-range, high-resolution radar and high data rate communication systems. A new class of broadband low power consumption active balun-LNA consisting of two common emitters amplifiers mutually coupled thru an AC stacked transformer for power saving and gain boosting. The active balun-LNA exhibits new high linearity technique using a constant gm cell transconductance independent of input-outputs variations based on equal emitters’ area ratios. A novel multi-stages active balun-LNA with innovative technique to mitigate amplitude and phase imbalances is proposed. The new multi-stages balun-LNA technique consists of distributed feed-forward averaging recycles correction for amplitude and phase errors and is insensitive to unequal paths parasitic from input to outputs. The distributed averaging recycles correction technique resolves the amplitude and phase errors residuals in a multi-iterative process. The new multi-stages balun-LNA averaging correction technique is frequency independent and can perform amplitude and phase calibrations without relying on passive lumped elements for compensation. The multi-stage balun-LNA exhibits excellent performance from 10 to 50 GHz with amplitude and phase mismatches less than 0.7 dB and 2.86º, respectively. Furthermore, the new multi-stages balun-LNA operates in current mode and shows high linearity with low power consumption. The unique balun-LNA design can operates well into mm-wave regions and is an integral block of the mm-wave radar and communication systems. The integration of several RFIC blocks constitutes the broadband millimeter-wave coexistent current mode direct conversion receiver architecture operating from 22- 44 GHz. The system and architectural level analysis provide a unique understanding into the receiver characteristics and design trade-offs. The RF front-end is based on the broadband multi-stages active balun-LNA coupled into a fully balanced passive mixer with an all-pass in-phase/quadrature phase generator. The trans-impedance amplifier converts the input signal current into a voltage gain at the outputs. Simultaneously, the high power input signal current is channelized into an anti-aliasing filter with 20 dB rejection for out of band interferers. In addition, the dissertation demonstrates a wide dynamic range system with small die area, cost effective and very low power consumption

mm-Wave Silicon ICs: Challenges and Opportunities

Millimeter-waves offer promising opportunities and interesting challenges to silicon integrated circuit and system designers. These challenges go beyond standard circuit design questions and span a broader range of topics including wave propagation, antenna design, and communication channel capacity limits. It is only meaningful to evaluate the benefits and shortcoming of silicon-based mm-wave integrated circuits in this broader context. This paper reviews some of these issues and presents several solutions to them

Mask Programmable CMOS Transistor Arrays for Wideband RF Integrated Circuits

A mask programmable technology to implement RF and microwave integrated circuits using an array of standard 90-nm CMOS transistors is presented. Using this technology, three wideband amplifiers with more than 15-dB forward transmission gain operating in different frequency bands inside a 4-22-GHz range are implemented. The amplifiers achieve high gain-bandwidth products (79-96 GHz) despite their standard multistage designs. These amplifiers are based on an identical transistor array interconnected with application specific coplanar waveguide (CPW) transmission lines and on-chip capacitors and resistors. CPW lines are implemented using a one-metal-layer post-processing technology over a thick Parylene-N (15 mum ) dielectric layer that enables very low loss lines (~0.6 dB/mm at 20 GHz) and high-performance CMOS amplifiers. The proposed integration approach has the potential for implementing cost-efficient and high-performance RF and microwave circuits with a short turnaround time

Radiometer-on-a-chip: a path toward super-compact submillimeter-wave imaging arrays

A novel approach for submillimeter-wave heterodyne imaging arrays is presented in this paper. By utilizing diverse technologies such as GaAs membrane based terahertz diodes, wafer bonding, bulk Si micromachining, micro-lens optics, and CMOS 3-D chip architectures, a super-compact low-mass submillimeter-wave imaging array is envisioned. A fourwafer based silicon block for a working W-band power amplifier MMIC is demonstrated. This module drastically reduces mass and volume associated with metal block implementations without sacrificing performance. A path towards super compact array receivers in the 500-600 GHz range is described in detail

A 77-GHz Phased-Array Transceiver With On-Chip Antennas in Silicon: Receiver and Antennas

In this paper, we present the receiver and the on-chip antenna sections of a fully integrated 77-GHz four-element phased-array transceiver with on-chip antennas in silicon. The receiver section of the chip includes the complete down-conversion path comprising low-noise amplifier (LNA), frequency synthesizer, phase rotators, combining amplifiers, and on-chip dipole antennas. The signal combining is performed using a novel distributed active combining amplifier at an IF of 26 GHz. In the LO path, the output of the 52-GHz VCO is routed to different elements and can be phase shifted locally by the phase rotators. A silicon lens on the backside is used to reduce the loss due to the surface-wave power of the silicon substrate. Our measurements show a single-element LNA gain of 23 dB and a noise figure of 6.0 dB. Each of the four receive paths has a gain of 37 dB and a noise figure of 8.0 dB. Each on-chip antenna has a gain of +2 dBi