Millimeter-Wave and Terahertz Systems-on-Chip for Radio ......Area 13100 um 2 NEP 1.5fw/Hz0.5 Gain 1.3ms/W Electrical Measurements Frequency Response Time -Encoded Output Imaging Results

Millimeter-Wave and Terahertz Systems-on-Chip for Radio, Radar and

Imaging Applications

HighHighHighHigh----Speed Electronics LaboratorySpeed Electronics LaboratorySpeed Electronics LaboratorySpeed Electronics Laboratory

RFIC Mini-Symposium, Tela Aviv University, July 3 2012

Prof. M.-C. Frank Chang

University of California, Los Angeles

Email: [email protected]

1

Outline

� Mm-Wave and Terahertz Systems-on-Chip

� Ultra-high-speed (>10Gbps) Near-Field-Communication (NFC)

Systems

� Broadband (57-64GHz) Self-Healing Radio-on-a-chip

� Mm-Wave to Terahertz (144-495GHz) Radar and Imaging

� Common Needs in Digital Controlled Artificial Dielectric


� Common Needs in Digital Controlled Artificial Dielectric

(DiCAD) with Reconfigurable/Tunable Permittivity

� Historical Artificial Dielectric

� Synthesizing DiCAD in Deep-Scaled CMOS

� Reconfigurable/Scalable DiCAD Circuit Designs • Linear phase shift and Impedance Matching• Direct frequency modulation/de-modulation• Broadband frequency synthesis• High PAE power amplifier

Near Field Communication Systems


Near Field Coupled “WaveConnector”


• Near-field-Communication at multi-Giga-Bit/sec– Ultra-high data rate (>10gbps) for short distance and

secured communications

– Protocol-transparent, near-universal applications

• Ends the electrical and mechanical compromises

WaveConnector in Action

• Link demonstration– Tiny, <1mm2 chips

• Smaller than the chip caps!

– Mounted along PCB edges

– 60 GHz carrier, ASK

Click image to play video


– 60 GHz carrier, ASK modulated

– Error-free operation over 10Gb/s up to a few centimeters

Closeup showing chips mounted

face-up and wire-bonded to PCB

RX

chip1

.2m

m

TX

chip

1.2

mm

0.6mm0.6mm

60GHz Self-Healing Radio-on-a-chip for

IEEE 802.11ad and WIGIG


IEEE 802.11ad and WIGIG

60GHz Radio-on-a-Chip (RoC)

UCLA students designing “Self-Healing Reconfigurable 4Giga-bit/sec Radio-on-a-Chip (RoC) for IEEE 15.3c, WIGIG, WLAN 11ad system applications”.


The 65nm CMOS RoC contains 57-65GHz Transmitter, Receiver, Frequency Synthesizer, ADC/DAC,

Digital Baseband……..

About 25million Transistors……………

57-64GHz Radio-on-a-Chip

Feature Value

Size 4.0 x 4.0 mm

Pads 145

On-Chip Cap 285 pF

Power Domains

44

RF Control 255


RF Frequency 57-65 GHz

BB Clock 2.0 GHz

In Color!

Metric UnitPhase I GNG

Performer Status to Date

Achieved Baseline Yield Post-Healing Yield

Performer Defined Metrics

Receiver (X)

NF dB <6 4 .6(Healed)* 0%* 100%*

Output Bandwidth GHz 1.2 >1.22- BL-OK* 100%* 100%*

Rx OIM3 dBc -40 <-41.3 BL-OK* 100%* 100%*

Transmitter

P1dB dBm 10 >12.5 BL-OK* 100%* 100%*

TX OIM3 dBc -40 -43 (Healed)* 0%* 100%*

* Based on Test Results from Ten Assembled Die-on-Boards

60GHz Radio-on-a-Chip System Performance Metrics/Yield


Synthesizer

Phase Noise dBc -90@ 1MHz -94@1MHz BL-OK* 100%* 100%*

Channel Frequency GHz58.32 + n ×××× 2.16N=0 … 3

Hit all tones with sufficient VCO margin*

100%* 100%*

I/Q mismatch dBc -40 -44.6 (Healed)* 0%* 100%*

ADC

ENOB Bit > 5.5 >5.8 BL-OK* 100%* 100%*

Program GNG Metrics

Performance Yield(1 % ≥ 75 100* 0%* 100*

Power Consumption Overhead

% ≤ 10 3.69%* 785mW* 785+29mW*

BL-OK*: Baseline Circuit Performance Met Specs Without Healing

60GHz 4Gbps Self-Healing Radio

Biasing

Self-Healing

RF Control

Clocking

Baseline


Before and After: Image Healing

Carrier

Image

Carrier

ImageImage-40 dBc

Carrier


Initial State Phase Healing Phase + Amplitude + DC

TX LO and Image (IQ) Healing System

Key Components

1. Knobs: the phase offset,

relative gains and DC offset

between TX I&Q channel are

controlled by the IQ unit.

2. The DAC controller provides

test tones for 1 tone and two 1 2

4


test tones for 1 tone and two

tone testing.

3. The envelope sensor at the

TX output captures the tone

information from the 60GHz

output spectrum.

4. The parameter estimator

evaluates and returns the

relative amplitudes of LO

leakage, and Image tone

power.

1 2

3

Code Sweep of Phase Correction vs. Image

Phase Sweep

� Result of code sweep

clearly shows that

there is a single local

minimum

corresponding to true

zero phase offset

between I and Q.


between I and Q.

� IQ Phase offset of

transmitter seems to

be about 7-10

degrees.

� Image level is still not

in spec because the

amplitude mismatch

still exists. This must

also be healed.

Code Sweep of Amplitude Correction vs. Image

Amplitude Sweep

� Once the phase is

correctly set the

amplitude must also

be adjusted to

obtain zero

mismatch between I

and Q.


� The I channel is

held at 255

amplitude so there

is about a 10 LSB

amplitude

mismatch.

� The image level is

can now reach

specification.

Code Sweep of DC Offset Control vs. LO Leak

DC Offset Sweep

� Result of code

sweep clearly

shows that there is

a single local

minimum

corresponding to


zero DC offset

between I and Q.

� Baseline already

meets GNG

requirements

without applying a

correction offset.

Linear Extrapolation with Cautious Control

Image and LO Healing Algorithm

� We expect the mismatch

will be less than 20

degrees for IQ angle, less

than 50 LSBs for amplitude

mismatch and less than 50

LSBs for LO leakage from

DC and so we do linear


DC and so we do linear

extrapolation to first

estimate the correct phase

setting.

� After the linear estimation

we can do a local 4% of

range sweep around the

estimated value with a

basic search in a small

solution space.

� First heal phase, then

amplitude, then DC offset

100% Yield from Image Tone Healing


100% Yield from TX OIM3 Healing


100% Yield from Noise Figure Healing


Mm-Wave to Terahertz (144-495GHz)

Imaging and Radar Systems


Imaging and Radar Systems

183GHz CMOS Active Imager

Measurement Value

Frequency 183 GHz

NF 9.9 dB

Power 13.5mW

Sensitivity -72 dBm

Area 13100 um2

NEP 1.5fw/Hz0.5

Gain 1.3ms/W

Electrical Measurements

Frequency Response Time-Encoded Output

Imaging Results


Frequency Response Time-Encoded Output

Sample-Targets (metals and non-metals)A) Metallic Wrench B) Computer floppy diskC) Football D) Roll of tape*All items were concealed in cardboard boxes

Digital Regeneration Receiver


Injecting fundamental power

into an oscillator shortens the

start-up time Adding a digital latch circuit allows the oscillator

to restart each clock. When the oscillator starts it

triggers the digital reset creating a pulse width

proportional to input power

DRR Prototype Test Results


Tri-Color (350/200/50GHz) IRR Imager(Inter-modulated Regenerative Receiver)

• First reported architecture for RX to operate above Fmax

• Fastest reported silicon receiver (SiGe or CMOS)

HighHighHighHigh----Speed Electronics LaboratorySpeed Electronics LaboratorySpeed Electronics LaboratorySpeed Electronics Laboratory 24

RX

Chopper Sync

• Fastest reported silicon receiver (SiGe or CMOS)• First multi-band sub-millimeter-wave receiver (3 bands)

350 GHz Chopper Response350 GHz Chopper ResponseCMOS Tri-band ReceiverCMOS Tri-band Receiver

495 GHz CMOS Super-Regenerative Receiver

495 GHz Regenerative Receiver

based on 40nm TSMC CMOS technology

with total power consumption of

5mW under 1V supply voltage


495GHz Image Capture

495 GHz Chopper Signal1. Sensitivity measurement of antenna-less 245 GHz

http://www.ee.ucla.edu/~atang/250_demo.mp42. 495 GHz antenna-less imager

http://www.ee.ucla.edu/~atang/494_demo.mp43. Imaging Radar Demo

http://www.ee.ucla.edu/~atang/Radar_Demo.mp4

Terahertz System Demonstrations

Reflective Mode Active Imaging


• Target is placed at a stand-off distance from imaging system containing source and detector and reflection is measured.

• The system must accommodate 2X the free space path loss of a regular radio link.

Low Physical Reflection Diversity

350 GHz 28 dBm

Bottle

MetalMetal

AcrylicBackdrop


• The above is illuminated with 28 dBm from a 350 GHz TWT source and detected with a 25fw/Hz0.5 receiver.

• Even with high power and low NEP the system is ineffective because the reflection diversity is too low (metal, plastic & fluid all have similar reflection coefficients).

MetalStand

Rail

Incidence Angle is Critical


• Rotating the target even off-axis eliminates the useful information in the image capture because the energy is not reflected back to the receiver [1].

0º Incidence 350 GHz

2º Incidence350 GHz

[1] Ken Cooper et.al. (NASA Jet Propulsion Lab) " Penetrating 3D Imaging at 4 and 25m Range Using a Sub-millimeter-Wave Radar” IEEE MTT 2008 V56 #12.

144 GHz CMOS Sub-Ranging 3D Imaging Radar with <0.7cm Depth Resolution

• First mm-wave 3D imaging radar in silicon!


Quasi-Optical Setup for 144 GHz

Radar

Presented at ISSCC 2012Presented at ISSCC 2012

144 GHz CMOS Sub-Carrier SAR 3D Imaging Radar Results

HighHighHighHigh----Speed Electronics LaboratorySpeed Electronics LaboratorySpeed Electronics LaboratorySpeed Electronics Laboratory 30Presented at ISSCC 2012Presented at ISSCC 2012

Required mm-Wave Device/Circuit Innovations

� Topology (circuit Architecture) to secure sufficient signal headroom

� Inter-stage circuitry to optimize I/O impedance and enhance signal gain

� High permittivity artificial dielectric to shrink


� High permittivity artificial dielectric to shrink dimensions of passives and reduce transmission / resonator / substrate loss over conductive Si substrate

� Embedded sensors/actuators/controller for self-diagnosis/healing to optimize system performance yield and counter system performance aging

Historical Artificial Dielectric


W.E. Kock, “Metallic delay lenses,” Bell Syst.

Tech. J, vol. 27, pp. 58-82, 1948

Historical Artificial Dielectric (II)


Induced Dipole Moment Boosts Permittivity in Capacitor

b

2

bE====φφφφ

b

Q+q2

bE

-qq

Ep


Eb

qQC

0

++++====′′′′

Loaded cell

0

0

C

C′′′′====κκκκ

Unloaded cell

2

bE−−−−====φφφφ -Q-q

2

bE

Eb

QC

0====

� Permittivity boost-factor

Capacitance Capacitance

� Array of identical

conducting obstacles

embedded in a dielectric

medium

� Displaced charges on

obstacles induce dipole

Artificial Dielectric

E

p

b c

z

Unit cell

εr


obstacles induce dipole

field

� Permittivity boost-factor

reduces resonant

wavelength and resonator

size

κκκκλλλλ

λλλλ medium

AD====

a

c

x

y

EPED κεκεκεκεεεεε ====++++====

abc

pNpP ========

CMOS Artificial Dielectric

l=λλλλ////4444

Transmission line guiding quasi-TEM wave

w

s

Cross-section view of E field vector

E

p

5

10

15

20

25

00

CC

′′ ′′== ==

κκ κκ


vector

t d

p 0

0.1 1 10 100 1000d(µµµµm)

Challenges in CMOS MM-Wave VCO

• High device flicker noise

– Large WL devices ?

– p-MOS ?

• Low-Q lumped passives

– Skin effect

– Substrate loss

AlGaAs/GaAs

HBT

Device Noises (IBM, 2003)

n-MOS

p-MOS

Ou

tpu

t n

ois

e (

A/√

Hz)


(((( ))))2

2

m

0

0

mQ

1

P

kTFRL

====

ωωωωωωωω

ωωωω

– Substrate loss

• Potential solutions

– Use distributed coplanar strip line resonator

– Enhance resonator’s Q with on-chip artificial dielectric

Leeson’s equation

SiGe HBTs

Frequency (Hz)O

utp

ut n

ois

e (

A/

VCO Die/Performance

10

0µ

m

Resonator with embedded artificial dielectrics

-94 dBc/Hz @100kHz

Offset


Varactor area

150µm

10

0

-107 dBc/Hz @ 1MHz

Offset

Performance Comparison

Reference Process f0 (GHz)VDD

(V)PDC

(mW)PN@1MHz (dBc/Hz)

FOMDie area (mm2)

This work90nm CMOS

60 1 1.9 -107 -200 0.015

J.Kim1 MTT-S,2003

InGaP/ GaAs HBT 60 3.5 158 -93 -167 0.78


B.A. Floyd2

RFIC,2004SiGe HBT 67 3 25 -98 -181 -

Y.Cho3

RFIC,20050.18µµµµm CMOS

53 2.1 27 -97 -177 0.20

R.Liu4

ISSCC,20040.25µµµµmCMOS

63 1.8 119 -85 -160 0.32

P.Huang5

ISSCC,20050.13µµµµm CMOS

57 1.2 8.4 -70 -136 0.20

Digitally Controlled Artificial Dielectric (DiCAD)

� Switch network inserted midway along virtual ground of the artificial dielectric strip (NMOS, π-configuration)

� Result: Digital control of effective dielectric constant!


DiCAD as Analog Control Knob

(a

)

(b

)

(c)


(d) (e)

(a) Two sections of 41.25um long DiCAD with 15 control switches each, under a differential TML with width of 22um and gap of 50um. The DiCAD bars are 5um wide with a pitch of 5.5um (space=0.5um); (b) for impedance match; (c) for impedance transformation; (d) for frequency selection; (e) for phase shift.

48GHz PLL Topology


� Type-II 3rd order Integer-N PLL

� Programmable divide chain (512 to 992, in steps of 32)

� DiCAD-based mm-wave blocks

mm-Wave Resonator Design Challenges


Goal � Minimise and Accurately for Parasitic Capacitance

DiCAD-Based Resonators


• DiCAD developed as a permittivity-

programmable transmission line

• Key Benefits:– Easily modelled, characterised and simulated

– Reduces parasitic concerns

– Enables “first-time right” mm-wave design

– Enables fine digital frequency tuning

Fundamental Trade-off

CRatio

Additional Resonator Design Choice


• DiCAD employed in all mm-Wave Blocks

– Ensures frequency alignment

• Resistor Array used as current source

– Reduces flicker noise

VCO Measurement Results (1)


� DiCAD controlled using 5-bit (32-state) thermometer code

� KVCO reduced below 1GHz/V across entire band

� 6 frequencies can be synthesized using 54MHz XO� 43.2GHz, 44.928GHz, 46.656GHz, 48.384GHz, 50.112GHz and 51.84GHz

VCO Measurement Results (2)


• Distributed nature of DiCAD and use of thermometer codes results in a very linear digital tuning

• Varactor-size can be minimised

Die Micrograph


(a) PLL Testchip (b) TRX Testchip

Comparison with State-of-the-Art


[1] O. Richard et al., ISSCC 2010, pp. 252–253, Feb. 2010

DiCAD for Linear Phase Shifter

� Linear phase change from -50.6o to -65.8o

� Linear increase in εεεεeff from 18.8 to 32 at 61GHz

� 35% of physically available range

• switch resistance and capacitance limit performance

Phase (S21) vs. freq. Phase, εr,eff vs. digital state


Phase (S21) vs. freq. Phase, εr,eff vs. digital state

Direct Frequency Vector Sum Modulator


� Take advantage of direct frequency architecture, and linear DiCAD

� Create and add two vectors in opposite quadrants to create sum vector that spans entire I-Q plane

� Quadrant Phase and Amplitude Shifters (QPAS) only need to work in a single quadrant.

DiCAD QPAS

� Design a dynamically matched amplifier with shunt/open

DiCAD stubs and series L networks (similar to Hi-Lo P.S.)

� Control phase with DiCAD and amplitude with NMOS


Switch Sequence

State 1: 00…0001

State 2: 00…0011

State 3: 00…0111

State n: 11…1111

Measured Modulation States

� Measured QPAS shows coverage (S21) of entire quadrant

� QPAS is well-controlled, and evenly distributed

� Measured 2562 total modulation points at 62.64GHz


DiCAD for Digital Constellations

� Measured (+) and ideal (o) constellation points.

� Static EVM < -31dB

BPSK π/2 QPSK


π/2 Star-8QAM π/2 16QAM

Summary

� Scalable SoC Designs based on Digital Controlled Artificial Dielectric (DiCAD)

� Synthesizing DiCAD in Deep-Scaled CMOS

� Reconfigurable/Scalable DiCAD Circuit Designs • Linear phase shift and Impedance Matching• Direct frequency modulation/de-modulation • Broadband frequency synthesis


• Broadband frequency synthesis• High PAE power amplifier

� Extensive System Applications in mm-Wave to Terahertz Spectra

� Ultra-high-speed (>10Gbps) Near-Field-Communication (NFC) Systems

� Broadband (57-64GHz) Self-Healing Radio-on-a-chip

� Mm-Wave to Terahertz (144-495GHz)Radar and Imaging

Documents

Millimeter-Wave and Terahertz Systems-on-Chip for Radio ......Area 13100 um 2 NEP 1.5fw/Hz0.5 Gain 1.3ms/W Electrical Measurements Frequency Response Time -Encoded Output Imaging Results