Ozgur Inac

A 76–84-GHz 16-Element Phased-Array Receiver With a Chip-Level Built-In Self-Test System

This paper presents a 16-element phased-array receiver for 76-84-GHz applications with built-in self-test (BIST) capabilities. The chip contains an in-phase/quadrature (I/Q) mixer suitable for automotive frequency-modulation continuous-wave radar applications, which is also used as part of the BIST system. The chip achieves 4-bit RF amplitude and phase control, an RF to IF gain of 30-35 dB at 77-84 GHz, I/Q balance of and at 76-84 GHz, and a system noise figure of 18 dB. The on-chip BIST covers the 76-84-GHz range and determines, without any calibration, the amplitude and phase of each channel, a normalized frequency response, and can measure the gain control using RF gain control. System-level considerations are discussed together with extensive results showing the effectiveness of the on-chip BIST as compared with standard S-parameter measurements.

A Phased Array RFIC With Built-In Self-Test Capabilities

An X-Band phased-array RF integrated circuit with built-in self-test (BIST) capabilities is presented. The BIST is accomplished using a miniature capacitive coupler at the input of each channel and an on-chip I/Q vector receiver. Systematic effects introduced with BIST system are covered in detail and are calibrated out of measurements. The BIST can be done at a rate of 1 MHz with 55 dB signal-to-noise-ratio and allows for the measurement of an on-chip array factor. Measurements done with BIST system agree well with S-parameter data over all test conditions. To our knowledge, this is the first implementation of an on-chip BIST with high accuracy.

A 76–84 GHz 16-element phased array receiver with a chip-level built-in-self-test system

A 16-element phased array receiver with built-in-self test (BIST) is demonstrated at 76-84 GHz. The BIST technique employs a miniature capacitive coupler located at the input port of each phased-array channel, and uses the receiver I/Q down-converter to measure the amplitude and phase of each channel. This allows for measuring the response of individual channels if one channel is turned on at a time, and an on-chip array factor if several channels are turned on and the phase between them is varied. BIST measurements done at 76-84 GHz agree very well with S-parameter measurements with a matched load and an open circuit load at each port, and show that this technique can be used to greatly lower the testing cost and improve the self-calibration of mm-wave phased-array RFICs.

A 108–114 GHz 4

This paper presents a W-band wafer-scale phased- array transmitter with high-efficiency on-chip antennas. The 4 × 4 array is based on an RF beamforming architecture with an equiphase distribution network and phased shifters placed on every element. The differential on-chip antennas are implemented using a 100 μm thick quartz superstrate and with a simulated efficiency of ~ 45% at 110 GHz. The phased array is designed with low mutual coupling between the elements and results in a stable active antenna impedance versus scan angle. The phased array is built in the Jazz SBC18H3 SiGe BiCMOS process, and is 6.5 × 6.0 mm2. Measurements show two-dimensional pattern scanning capabilities with a directivity of 17.0 dB, an array gain of ~26.5 dB at 110 GHz, and an EIRP of 23-25 dBm at 108-114 GHz. The power consumption is 3.4 W from a 1.9 V supply. To our knowledge, this work represents the first W-band wafer-scale phased array to-date. The application areas are in point-to-point communication systems in the 100-120 GHz range.

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This paper presents the first built-in self-test system (BIST) for W-band transmit-receive phased-array modules. Low-loss high-isolation switches are attached to the RF input and output ports using λ/4 transmission-line sections, which result in a high shunt impedance when the BIST is disabled and minimal penalty in additional loss. A W-band in-phase/quadrature down-conversion mixer/receiver with 0.5-dB amplitude and 4°-5° phase imbalance at 90-100 GHz is also implemented on-chip and is used as an on-chip vector network analyzer. The BIST allows the measurement of the normalized S21 in both transmit and receive modes with high accuracy (4-bit phase response, 0.5-dB amplitude variation) at 90-100 GHz without any external calibration. The BIST also results in a normalized frequency response that agrees well with the measured S-parameters at 90-100 GHz.

4 Wafer-Scale Phased Array Transmitter With High-Efficiency On-Chip Antennas

This paper presents the first simultaneous 8-transmit and 8-receive paths 75-85 GHz phased array RFIC for FMCW automotive radars. The receive path has two separate I/Q mixers each connected to 4-element phased arrays for RF and digital beamforming. The chip also contains a build-in-self-test system (BIST) for the transmit and receive paths. Measurements on a flip-chip prototype show a gain >24 dB at 77 GHz, -25 dB coupling between adjacent channels in the transmit and receive paths (<;-45 dB between non-adjacent channels), and <;-50 dB coupling between the transmit and receive portions of the chip.

A 90–100-GHz Phased-Array Transmit/Receive Silicon RFIC Module With Built-In Self-Test

This paper presents low-noise amplifiers (LNA) at 45¿C95 GHz, a frequency doubler at 180 GHz, active and passive mixers at 130¿C180 GHz fabricated in 45-nm Semiconductor-On-Insulator (SOI) CMOS process for digital and mixed-signal applications. The measured ft and fmax of a 30¡A1-¿Im transistor are 200 GHz at 0.3 mA/¿Im current density, referenced to the top metal layer. The measured gain and NF of LNAs are 15¿C11 dB and 3.3¿C6.0 dB at 45¿C95 GHz. The balanced doubler results in an output power of 1 mW and 8 dB conversion loss at 180 GHz. Passive double-balanced and active single-balanced mixers achieve conversion loss of 12¿C13 dB at 130¿C180 GHz, and 4 dB with 3-dB bandwidth of 145¿C161 GHz, respectively. This work shows that 45-nm SOI CMOS process results in state-of-the-art performance for millimeter-wave applications.

75–85 GHz flip-chip phased array RFIC with simultaneous 8-transmit and 8-receive paths for automotive radar applications

This talk will present our latest work on silicon RFICs for phased-array applications with emphasis on very large chips with built-in-self-test capabilities for 5G systems. SiGe is shown to be ideal for mm-wave applications due to its high temperature performance (automotive radars, base-stations, defense systems, etc.) and lower power consumption. These chips drastically reduce the cost of microwave and millimeter-wave phased arrays by combining many elements on the same chip, together with digital control and some cases, high-efficiency antennas. The phased-array chips also result in an easier packaging scheme using either a multi-layer PCB or wafer-level packages. We believe that this family of chips will be essential for millimeter-wave 5G communication systems.

Millimeter-Wave and THz Circuits in 45-nm SOI CMOS

This paper presents wideband passive and active mixers in the 100–200 GHz range. The mixers are built using a 45nm CMOS SOI process with an ft of 220 GHz when referenced to the top metal layer. The passive double-balanced mixer results in a conversion loss of 12–13 dB from 130–180 GHz (including balun, transmission line and GSG pad losses) and achieves optimal performance with 3 dBm of LO power (referenced to the GSG LO pads). The active mixer achieves a conversion loss of 4.5 dB with a 3-dB bandwidth of 145–165 GHz, and consumes only 10 mW of DC power from a 1.5 V supply. The application areas are in wideband Gbps communications, imaging arrays with large IF bandwidths, and mm-wave spectrometers. To our knowledge, this work represents the first demonstration of high performance CMOS mixers in the 130–180 GHz frequency range.

Millimeter-wave large-scale phased-arrays for 5G systems

This paper presents the first 16-element 77-81 GHz phased array receiver for automotive radars. The silicon phased array chip is packaged using very low-cost techniques, and is attached to a 16-element linear microstrip antenna array. The packaging is designed to result in <; -28 dB coupling between the channels even with wirebonds. The measured patterns show scanning to ±50o and agree well with simulations. The 16-element phased array receiver has been implemented with a transmitter and shows detailed images of targets and scenes in outdoor driving scenarios.