IEEE固态电路期刊2019年9月特辑：集成电路设计

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"这篇文章摘自2019年9月的IEEE固体状态电路期刊(JSSC-2019-9)，该期刊专注于固态电路的晶体管级设计，特别是集成电路(IC)的设计。该期包含了一个特别板块，专门讨论2018年IEEE BCICTS会议，并发表了几篇经过同行评审的论文，涵盖了高速调制器、时间交错闪存ADC、宽带雷达、GaN-on-SiC功率放大器以及In0.8Ga0.2As MOSHEMT毫米波集成电路技术等领域。此外，还有一篇关于全集成W波段相控阵的文章和一篇涉及多相RF-LO的115-135 GHz 8PSK接收机设计的论文。所有文章均经过至少两位独立审稿人的单盲评审流程，以确保研究质量和学术诚信。" 这篇摘要揭示了多个重要的IT和电子工程领域的知识点： 1. **固态电路**：这是集成电路设计的基础，主要关注使用半导体材料如硅来构建的电路，这些电路在现代电子设备中起着核心作用。 2. **集成电路(IC)**：这是一种将多个电子元件（如晶体管、电阻和电容）集成在单一芯片上的技术，大大减小了设备的体积并提高了性能。 3. **IEEE Journal of Solid-State Circuits**：这是一个国际认可的期刊，其发表的内容代表了固态电路领域的最新研究和进展。 4. **同行评审**：这是科研出版过程中的关键环节，确保文章的科学性和准确性。在这个过程中，专家匿名评审稿件，提供反馈，以提升研究质量。 5. **2018年IEEE BCICTS会议**：这是一个专业会议，展示了在集成电路和通信技术方面的最新研究成果，是研究人员交流思想和经验的平台。 6. **高速调制器**：如文章中提到的宽频I/Q CMOS调制器，用于高速数据传输，如100-200 Gb/s，对于5G通信和光纤应用至关重要。 7. **时间交错闪存ADC**：这是一种模拟数字转换器，通过时间分隔提高采样率，如文中55nm SiGe BiCMOS设计，适用于64-Gbd 16-QAM光纤应用。 8. **宽带雷达**：用于非破坏性测试，例如对复合材料进行检测，240-GHz雷达系统具有广阔的应用前景。 9. **GaN-on-SiC功率放大器**：GaN（氮化镓）材料在高效率功率放大器中的应用，如文中所示的18.5-24 GHz 4W PA，适合射频和微波通信。 10. **In0.8Ga0.2As MOSHEMT毫米波集成电路技术**：这种异质结场效应晶体管技术在毫米波频率下的高性能集成电路设计中扮演重要角色。 11. **全集成W波段相控阵**：这涉及到天线阵列的设计，能够实现自对准和自测试，提高了无线通信系统的性能和可靠性。 12. **多相RF-LO的115-135 GHz 8PSK接收机**：8PSK（8相移键控）是一种调制技术，用于提高无线信号的传输速率和效率，多相RF-LO（本地振荡器）在接收机中的应用有助于信号的解调和处理。以上这些知识点体现了当前电子工程和集成电路设计领域的前沿技术和研究趋势，对相关领域的专业人士和学者具有很高的参考价值。

2370 IEEE JOURNAL OF SOLID-STATE CIRCUITS, VOL. 54, NO. 9, SEPTEMBER 2019

Fig. 18. (a) Chip micrograph. (b) I/Q modulator measurement setup.

and sets the dynamic range of the 100–200 Gb/s measurement

setup.

1) SSB Suppression and Carrier Feedthrough: To evaluate

the transmitter dynamic range, it is ﬁrst conﬁgured as a

single-sideband (SSB) transmitter to measure the LO leakage

and SSB suppression. Furthermore, SSB suppression will indi-

cate the quality of the IQ generator in terms of its amplitude

and phase mismatch. A 100-MHz tone is generated using an

AWG that is controlled in software by MATLAB, such that the

ﬁrst channel of the AWG generates the 100-MHz sinusoidal

tone and the second channel generates the Hilbert transform

(quadrature signal in the case of a single tone) of the signal

in channel 1. The two channels are synchronized and phase

adjusted such that the two quadrature signals arrive at the I and

Q input data pads of the die with correct phases. The output of

the transmitter is then connected to a spectrum analyzer, where

the LO leakage and SSB suppression are readily determined.

Fig. 19 shows the measured sideband suppression and

LO leakage as a function of the LO frequency. Sideband

Fig. 19. SSB and LO leakage measurements.

Fig. 20. EVM and ACPR measurements versus backoff level at an

LO (carrier) of 5 GHz. (a) 64-QAM with 100 Mbaud. (b) 256-QAM with

100 Mbaud.

suppression is measured by ﬁrst determining the phase setting

to account for the mismatch between the I and Q paths at

100 MHz that is due to the measurement setup, then the LO

frequency is swept without changing any phase settings from

the AWG. This determines the true wideband performance

of the I/Q modulator chip. The measured SSB suppression

is >30 dB over the entire DC-50 GHz band.

Fig. 19 also shows that the LO leakage can be as high

as −25 dBc—normalized to the transmitted power—prior to

calibration. The increase in carrier feedthrough with frequency

is expected and has been discussed in Section II-C. After cali-

bration, the leakage levels are signiﬁcantly improved down to a

worst case level of −50 dBc. The optimum calibration settings

vary for each LO frequency, even though the IF frequency is

ﬁxed at 100 MHz. This is due to frequency-dependent leakage

mechanisms such as the direct LO to RF leakage through the

transistor parasitics and supply network. The output of the

I/Q transmitter is measured in a single-ended fashion, which

further contributes to the LO feedthrough. This is because

external or on-chip baluns are limited in BW and are not

capable of covering the DC-60 GHz frequency range.

Given the worst case SSB rejection and carrier feedthrough

of 35 dB (at an LO of 35 GHz) and −50 dBc, respectively,

a worst case EVM of approximately 1.8% is to be expected,

limiting the use of very-high order modulation formats such

as 256-QAM and 1024-QAM to LO carrier frequencies below

20 GHz (where the SSB rejection is > 45 dB).

2) Linearity Measurements: Fig. 20 shows the measured

EVM and ACPR at a 5-GHz carrier for 64-QAM and

256-QAM. As expected, both ACPR and EVM are minimum

AL-RUBAYE AND REBEIZ: ANALYSIS AND DESIGN OF WIDEBAND I/Q CMOS 100–200 Gb/s MODULATORS 2371

Fig. 21. Equalization effects for a 28-GHz carrier. (a) 16-QAM with

100 Mbaud. (b) 64-QAM with 100 Mbaud.

Fig. 22. Quadrature amplitude and phase errors versus backoff level at

28 GHz. (a) 16-QAM with 100 Mbaud. (b) 64-QAM with 100 Mbaud.

at certain backoff levels, above which they degrade due to

non-linear distortion. Increasing the backoff level degrades the

EVM and ACPR due to CFT and SNR degradation.

Fig. 21 shows the beneﬁt of applying linear equalization

to the measured EVM of 100-Mbaud signals at a 28-GHz

carrier. In general, signiﬁcant improvement in the measured

EVM is observed, even over narrow modulation bandwidths.

At 100-MHz BW, the frequency response of the circuit can

be assumed ideal, and therefore, any ISI resulting from

non-ideal amplitude and phase response of the channel arises

from the measurement setup. Furthermore, as the backoff

level decreases the EVM becomes dominated by non-linear

effects and the equalized and non-equalized results become

comparable.

Fig. 22 shows the measured quadrature amplitude and phase

errors at 28 GHz as a function of the backoff level. Initially,

the quadrature amplitude and phase errors are small owing

to the accuracy of the digital CML IQ generator. As the

input power to the baseband transconductance stages increases,

AM–AM and AM–PM distortions lead to data-dependent

quadrature amplitude and phase errors. Simulations of the

double-balanced mixer show 2

◦

of AM–PM distortion at

P1dB, which directly translates to phase errors in the Cartesian

IQ transmitter.

3) Single-Carrier Measurements: Single-carrier modulation

measurements of the I/Q modulator were carried out up to

63 GHz. Since the differential signal source is limited to

70 GHz, the transmitter operates in direct-conversion mode

up to 35 GHz and in a heterodyne mode with SSB rejection

above 35 GHz.

Fig. 23 shows the measured EVM versus data rate for

various carrier frequencies and modulation formats up to

Fig. 23. (a) Measured EVM versus baud rate for different modulation formats

at a 28-GHz carrier. (b) Measured output spectrum of a 1-Gbaud 16-QAM

modulated signal with a RRC ﬁlter applied (rolloff factor α = 0.15). (c) 5-

GHz measurements. (d) 15-GHz measurements. (e) 35-GHz measurements.

(f) 60-GHz measurements.

Fig. 24. Measured constellations at 28 GHz for various modulation formats,

demonstrating low-EVM at (a) 64-QAM/1-GHz BW and peak data rate

of 200 Gb/s, (b) 16-QAM/50-GHz BW, and (c) 32-QAM/40-GHz BW.

60 GHz. Measurements of the modulator proved its capa-

bility of supporting a maximum baud rate of 60 Gbaud/s

in QPSK (120 Gb/s), 50 Gbaud/s in 16-QAM (200 Gb/s),

40 Gbaud/s in 32-QAM (200 Gb/s), and 20 Gbaud/s

in 64-QAM (120 Gb/s). The measurement was carried out at

6-dB backoff and with an expected worst case BER better

than 10

−3

. To the best of authors’ knowledge, this the ﬁrst

demonstration of transmit data rates exceeding 100 Gb/s in

silicon technologies. Fig. 24 shows examples of measured

constellations at 28 GHz.

2372 IEEE JOURNAL OF SOLID-STATE CIRCUITS, VOL. 54, NO. 9, SEPTEMBER 2019

TABLE I

OMPARISON WITH THE STATE-OF-THE-ART ULTRAWIDEBAND

TRANSMITTERS IN SILICON TECHNOLOGIES

Fig. 25. Demonstration of 5G mm-wave carrier aggregation at 28 and

39 GHz using the wideband I/Q modulator. (a) 32 Gb/s, 4.8% EVM at

28 GHz. (b) 32 Gb/s, 7% EVM at 39 GHz. (c) Measured spectrum showing

simultaneous transmission of the two carriers.

Table I gives a comparison with state-of-the-art modulators

and transmitters. A signiﬁcant improvement is demonstrated

in the data throughput and energy/bit efﬁciency. The output

power can be increased using wideband distributed ampliﬁer

topologies [28].

Fig. 26. Demonstration of 5G mm-wave carrier aggregation at 28 and

60 GHz.

Fig. 27. Measured spectrum and constellation of 100-MHz 64-QAM OFDM

signal at 28 GHz with −31.8 dB EVM.

4) Multi-Carrier Measurements: Single-channel wideband

modulations are highly susceptible to channel impairments,

such as multi-path fading, and are generally difﬁcult to process

efﬁciently in baseband. Therefore, carrier aggregation tech-

niques are expected to be a driving technology in future wide-

band communication systems. Inter-band carrier aggregation

of mm-wave systems is of particular interest for ultra-high

data rate scenarios.

Fig. 25 demonstrates an example of an ultra-wideband 5G

carrier aggregation link, where 2 × 8 Gbaud 16-QAM signals

are modulated with 28- and 39-GHz carriers, resulting in a

record aggregate data rate of 64 Gb/s.

Fig. 26 shows another mm-wave carrier aggregation sce-

nario where 28- and 60-GHz carriers were simultaneously

modulated, each at 100 Mbaud and in 16-QAM, resulting

in 800-Mbps aggregate data rate. The transmitter operates

in direct-conversion mode for the 28-GHz carrier and as an

image-rejecting wideband-IF transmitter at 60 GHz.

Similarly, multi-carrier OFDM waveforms are expected to

be highly used in mm-wave 5G due to their spectral efﬁciency

and efﬁcient MIMO implementation. Fig. 27 shows the mea-

surement of a 100-MHz 64-QAM 52-subcarriers OFDM signal

at 28 GHz, with −31.8-dB EVM at 10-dB backoff.

V. C

ONCLUSION

A wideband state-of-the-art DC-60 GHz I/Q modula-

tor/transmitter chip in 45-nm SOI CMOS was presented.

The 1.4 mm

(0.18 × 0.1 mm

core) modulator consists of

AL-RUBAYE AND REBEIZ: ANALYSIS AND DESIGN OF WIDEBAND I/Q CMOS 100–200 Gb/s MODULATORS 2373

a wideband quadrature signal generator, wideband buffers,

and two current-combined DC-100 GHz low-noise double-

balanced mixers. The I/Q modulator achieves 200 Gb/s

in 16-QAM (50 Gbaud/s), while consuming 200 mW, resulting

in a record 1-pJ/bit modulation efﬁciency. In addition to

backhaul links, the modulator is an attractive and cost-effective

alternative to short-range optical links for data center intercon-

nects (DCI) applications. Future work may include increasing

the modulator output power to alleviate the need for an

additional power ampliﬁer stage.

CKNOWLEDGMENT

The authors would like to thank Keysight for the

M8196 AWG and for technical support and Integrand for the

EMX simulation software.

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Hasan Al-Rubaye (S’11) received the B.Sc. degree

in electrical engineering from the University of

Toronto, Toronto, ON, Canada, in 2013, and the

Ph.D. degree from the University of California at

San Diego (UCSD), San Diego, CA, USA, in 2018.

He held internships with Advanced Micro

Devices (AMD) and Nokia Bell Labs, where he

was involved in research and development efforts in

mm-wave phased array systems. From March 2018

to June 2019, he was at Roshmere, Inc., working

on 64 Gbaud RF front ends for 400G and 800G

optical coherent systems. He is currently an R&D IC Design Engineer in the

Wireless Communications and Connectivity (WCC) division at Broadcom,

Inc., San Diego, CA.

Dr. Al-Rubaye was a recipient of the ISSCC Analog Devices Outstanding

Designer Award and the Best Conference Paper Award twice during the course

of his graduate studies.

2374 IEEE JOURNAL OF SOLID-STATE CIRCUITS, VOL. 54, NO. 9, SEPTEMBER 2019

Gabriel M. Rebeiz (S’86–M’88–SM’93–F’97))

received the Ph.D. degree from the California Insti-

tute of Technology, Pasadena, CA, USA.

From 1988 to 2004, he was with the University

of Michigan, Ann Arbor, MI, USA. His group

has optimized the dielectric lens antenna that is

the most widely used antenna at millimeter-wave

and terahertz frequencies. His group also developed

6–18-GHz, 30–35-GHz, 40–50-GHz, 77–86-GHz,

and 90–110-GHz 8- and 16-element phased arrays

on a single silicon chip, the ﬁrst silicon phased-array

chip with built-in self-test capabilities, the ﬁrst wafer-scale phased arrays with

on-chip antennas, and the ﬁrst SiGe millimeter-wave silicon passive imager

chip at 85–105 GHz. His group also demonstrated high-performance RF

MEMS tunable ﬁlters at 0.7–6 GHz, RF MEMS phase shifters at 1–100 GHz,

and high-power high-reliability RF MEMS metal-contact switches. As a

Consultant, he helped to develop 24- and 77-GHz single-chip SiGe automotive

radars, phased arrays operating at X- to W-band for defense and commercial

applications (SATCOM, automotive, and point to point), digital beamforming

systems, and several industrial RF MEMS switches. He has graduated

72 Ph.D. students and 22 Post-Doctoral Fellows. He currently leads a group

of 22 Ph.D. students and Post-Doctoral Fellows in the area of millimeter-wave

radio frequency integrated circuits (RFICs), tunable microwaves circuits,

RF MEMS, planar millimeter-wave antennas, and terahertz systems.

He is currently a Distinguished Professor and the Wireless Communications

Industry Chair Professor of Electrical and Computer Engineering with

the University of California at San Diego (UCSD), San Diego, CA,

USA. He has authored or coauthored more than 720 IEEE publica-

tions. He has authored RF MEMS: Theory, Design and Technology

(Wiley, 2003).

Dr. Rebeiz is a member of the National Academy. He was a National

Science Foundation Presidential Young Investigator and the 2003 IEEE

Microwave Theory and Technique Society (MTT-S) Distinguished Young

Engineer. He was a recipient of an URSI Koga Gold Medal, the IEEE MTT-S

2000 and 2014 Microwave Prize, the IEEE MTT-S 2010 Distinguished Edu-

cator Award, the IEEE Antennas and Propagation Society (AP-S) 2011 John

D. Kraus Antenna Award, the 2012 Intel Semiconductor Technology Council

Outstanding Researcher in Microsystems, the R&D100 2014 Award for this

work on phased-array automotive radars, the 2014 IEEE Daniel E. Noble

Field Medal for his work on RF MEMS, the IEEE AP-S 2015 Harold A.

Wheeler Applications Prize Paper Award, the 1997–1998 Eta Kappa Nu

Professor of the Year Award, the 1998 College of Engineering Teaching

Award, the 1998 Amoco Teaching Award given to the Best Undergraduate

Teacher at the University of Michigan, and the 2008 Teacher of the Year

Award of the Jacobs School of Engineering, UCSD. His students were the

recipient of 23 Best Paper Awards from the IEEE MTT-S, RFIC, and AP-S

Conferences. He serves as a Distinguished Lecturer for the IEEE MTT-S,

the IEEE AP-S, and the IEEE Solid-State Circuit Society. He serves as an

Associate Editor for the IEEE T

RANSACTIONS ON MICROWAVE THEORY

AND TECHNIQUES.

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IEEE固态电路期刊2019年9月特辑：集成电路设计

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