Advanced Technologies for Highly Integrated RFIC … · Advanced Technologies for Highly Integrated...

Advanced Technologies for Highly Integrated RFIC Modules for Future Wireless

Communications

Deuk Hyoun Heo Ph. D.

January 22, 2003

Department of Electrical and Computer EngineeringWINLAB

Rutgers University, Piscataway, NJ

Georgia Tech

• Location: Atlanta, Georgia USA

– Masters Golf Tournament

– Coca-Cola Headquarters

– Delta

– CNN Headquarters

– Atlanta Braves Baseball

Georgia Institute of Technology

Introduction

Compact Silicon Based Power Amplifier Module

Passive on Chip and Passive on Package

Prototype Demonstration

CMOS/SiGe HBT DECT and Home RF Power Amplifier Module

Compact GaAs Based RF Front-End Module

3D Integrated Embedded Passive Implementation

Prototype Demonstration

802.11a WLAN RF Front-end Module

Future Work

Outline

Overview of Wireless Applications

3GPP2Mbps2GHz

3GPP2Mbps2GHz

BroadbandMobile Cellular

ETSI/MMAC/ITS34Mbps

40/60GHz

BroadbandMobile Cellular

ETSI/MMAC/ITS34Mbps

40/60GHz

mmw WLANETSI/MMAC

155~200Mbps60GHz

mmw WLANETSI/MMAC

155~200Mbps60GHz

Fixed Point-PointIEEE802.16 BWA

16~134Mbps/1Gbps10~66GHz

Fixed Point-PointIEEE802.16 BWA

16~134Mbps/1Gbps10~66GHz

10Mbps 100Mbps 1Gbps1Mbps

Fixed Point-MultipointBWIF

~20Mbps2.6GHz

Fixed Point-MultipointBWIF

~20Mbps2.6GHz

WLAN 802.11a

IEEE/BRAN/ARIB2~54Mbps

5GHz

WLAN 802.11bIEEE/Hiperlan

2/11Mbps2.4GHz

WLAN 802.11bIEEE/Hiperlan

2/11Mbps2.4GHz

Wireless1394802.11a/1394-TA/MMAC

54 ~ 100Mbps5/20/60GHz

Wireless1394802.11a/1394-TA/MMAC

54 ~ 100Mbps5/20/60GHz

Hightier/MobileCellular

Movable/WLAN

Fixed/Data Bridge

Mobility

Data Rate

Next Gen./mmw Wireless Comm.

-Introduction-PA Module-3D RF front-end-Future Goal


Low Cost

Small Size

Smart RF

Passive Losses

Interference

Longer Design Cycle

System-on-Chip (SOC) for RFSystem-on-Chip (SOC) for RF

Advantages

Disadvantages



Replace discrete components to embedded oneAdd functionality in the package : (filter, balun, antenna)Realize High-Q embedded passives : (high-Q Inductors)

“to provide single package solution by integrating embedded passives and RFIC using State-of-the-Art packaging technology.”

System-on-Package (SOP) for RFSystem-on-Package (SOP) for RF

What is RF-SOP ?-Introduction-PA Module-3D RF front-end-Future Goal


SOC in SOPSOC in SOP

AntennaUp-Conv

PA

LNA

Down-Conv

VCOBasebandBaseband

IF &Analog

IF &Analog

FLT

FLT

MA

DPLX

SOP SOC-Introduction-PA Module-3D RF front-end-Future Goal


MMIC

PackagePackage

LNALNA

MixerMixer

VCOVCO

PAPA

AntennaAntenna FilterFilter

BalunBalun

High-Q L/CHigh-Q L/C

Driver AmpDriver AmpDuplexerDuplexer

SwitchSwitch

Power CombinerPower Combiner

Technical Mapping-Introduction-PA Module-3D RF front-end-Future Goal


MMIC + Embedded Passives

Multi-layer Filter

PlanarAntenna

3D RF Front-End Module -Introduction-PA Module-3D RF front-end-Future Goal


Development of RF-SOP

System SimulationModule Integration

MMIC design

Passive design

MMIC

PackagePackage

LNALNA

MixerMixer

VCOVCO

PAPA

AntennaAntenna FilterFilter

BalunBalun

High-Q L/CHigh-Q L/C

Driver AmpDriver AmpDuplexerDuplexer

SwitchSwitch

Power CombinerPower Combiner

• Compact Silicon Based PowerAmplifier Modules

Introduction

Power Amplifiers in RF transmitters

Consume Most of Power in Transmission Mode

Linearity

Cost

Cost Reduction Strategy

Silicon-Based Technology

High levels of Integration

-IntroductionPA Module-3D RF front-end-Future Goal


Issues of CMOS PA

Transistor Characteristics

Low Breakdown Voltage

High Knee Voltage

Passive Component

Lossy Si substrate

Thin Metal Layers



Silicon Based Power Amplifier Modules

CMOS PA Integrated with Chip Passives

CMOS PA Integrated with MEMS Passives

CMOS PA Integrated on Package

Input/Output Matching on LTCC

SiGe HBT PA Integrated on Package



Patterned Ground Shield On-Chip Inductor

FOX+-Diffusion

OxideOxide

Si

Via Via

PolysiliconFOX

ViaMetal-1

Metal-2

Passivation

PolysiliconN+-Diffusion

OxideOxide

Si

Via Via

Polysilicon



Poly-Silicon Patterned Ground

Q of the Inductor with PG is lower than that of the Inductor without PG.

The Inductor Trace Close to PG introduces Additional Parasitic Capacitance

Additional Parasitic Capacitance degrades the Q of the Inductor



Improvement of Patterned Ground

N+-Diffusion layer is used to implement PG

Much less Parasitic Capacitance is introduced by

N+-Diffusion PG

Q can be enhanced up to 20%

Effective Inductance is not affected by PG



2.4 GHz Integrated Power Amplifier

2.4 GHz, 2.5 V operation22 dBm Output Power, More than 20 % PAE0.24-µm CMOS technology

Double poly capacitors on chipInter-stage matching circuits on chip



2:4 Decoder

EN S2 S1

Y3

Y2

Y1

Y0

VG

VDD

Driver PA

RF OUT (12, 16, 20, 24 dBm)

RF IN

GateBias

Controller

DIGITALINPUTS

Power Control Circuit for PA-IntroductionPA Module-3D RF front-end-Future Goal


Micromachined Solenoid Inductor

w s

t

h

Si

g

Su-8Cu

SiO2

wc

Solenoid

coil

A

A’

Extended pad

Perspective view

Cross-sectional view of A-A’

Si CMOS wafer

SU-8 epoxy

SiO2Au pad

Si CMOS wafer

Electroplated copper

SU-8 epoxy

SiO2Au pad

#1

#2



2.4 GHz CMOS PA with MEMS Inductors-IntroductionPA Module-3D RF front-end-Future Goal


On-Package Inductors in LTCC Technology

Ground Plane

Top view

Cross-sectional View

Planar Spiral Conventional3-D Helical

Modified Conventional3-D Helical

Novel 3-D Helical

Modified Novel 3-D Helical



0

20

40

60

80

100

120

0 1 2 3 4 5 6 7

4.0 nH5.4 nH

2.5 nH3.8 nH

1.2 nH1.4 nH

Q

Frequency, GHz

0

2

4

6

8

10

0 1 2 3 4 5 6 7

4.0 nH5.4 nH

2.5 nH 3.8 nH

1.2 nH1.4 nH

L eff, n

H

Frequency, GHz

Circular Turns : Half, Three-Quarter, Full TurnsLine Width W=10, 20 milsh=2,6,10,14,18 layersLeff : 1 - 8 nH, Q : 55~100

LTCC Inductor Performance-IntroductionPA Module-3D RF front-end-Future Goal


Vertically Interdigitated Capacitor (VIC)

VIC TopologyApplicable to Multi-Layer MCM,Semiconductor and MEMSComparable Q and SRF to MIM topology

Quality factor and Effective Capacitance Capacitance of 1.1 pF ( ) and 1.9 pF ( ).



1.9 GHz CMOS-LTCC Power Amplifier

On Chip

On LTCC

1.9 GHz, 3 V operationInter-stage matching is on chipCMOS technologyOther matching and chokes are on LTCCDC blocks are included in the matching networksTwo stage common-source configuration



1.9 GHz Fully Integrated CMOS-LTCC PA

1.9 GHz, 3 V operationCMOS technologyAll of the matching and chokes are on LTCCDC blocks are included in the matching

networks Two stage common-source configuration



2.4 GHz CMOS-LTCC Power Amplifier

Power MOSFET device : MOSFET Size : 3mm 23 dBm and 45 % PAE at 2.4 GHz Vds=2.5 V 3D LTCC Passives Thermal and Electrical Path using Multiple ViaSolid and Mesh Ground Plane ( L << lamda/10)VIC Topology : RF GNDSize : 8 mm X 15 mm



Power Amplifier in a Si-based Technology

SiGe HBT ⇒ HBT Device Advantages in Si

Enhance Native Device Performance

Class F-like Loading ⇒ High EfficiencyHarmonic Suppression Filter (HSF)

-3-

SiGe HBT Power Amplifier-IntroductionPA Module-3D RF front-end-Future Goal


Load impedanceSecond Harmonic ShortOpen at Third harmonic

Performance Enhancements0.6 dB Additional powerNo power Dissipation at Harmonics90 % Efficiency

NeededCompact Implementation of Load Network

-5-

Class F Operation-IntroductionPA Module-3D RF front-end-Future Goal


Bias Block II

Bias Block I

Bias Block III

Output Match

Harmonic Suppression

Filter

Vcc Vcc Vcc

Bias Block II

Bias Block I

Bias Block III

Output Match

Harmonic Suppression

Filter

Vcc Vcc Vcc

IBM SiGe 5HP BiCMOS Process => IBM 7HP and 8HP

High Breakdown Device used (BVceo = 5.5 V)

Packaged in an 8 pin Mini-SOIC Package

-10-

2.4 GHz SiGe HBT Power Amplifier-IntroductionPA Module-3D RF front-end-Future Goal


Ic = I so.expqVbe − qIc

re + Rebα

+ rbβ

− Eg

kT

T = TA + Rth Ic Vcc

Rth = ln(4L/W) / (πkL) ~ 0.81 oC/mW

TA = 125 oC

Eg(T) = Eg0 - 3.6 x 10-4 T

Eg0 = 1.21 eV

β(T) = β(To) (T/ To)XTB

To = 298K, XTB= -0.5

→ (∂Jc / ∂Vbe)-1 = 0

Reb = 3 Ω per transistor used

-9-

Ballast Resistor Design

0.5 0.6 0.7 0.8 0.9 1 1.1 1.20.1

1

10

Reb= 0 Ω

Reb= 1 Ω

Reb= 2 Ω

(∂Jc/ ∂Vbe)-1 = 0

Vbe (V)

J c (m

A/µ

m2 )

Reb= 3 Ω



Novel Base Ballasting for SiGe HBT PA design

Emitter ballasting Loss of voltage swing and gain

Base ballastingRbb ~ βRebLoss of RF power in base ballasting resistance (~ 1Ω)Solution : Remove ballast resistance from RF path

Bias network

Bias network Bias

network

Emitter Ballasting Traditional Base Ballasting Novel Base Ballasting



Biasing for SiGe HBT PAs

First order model of bipolar transistor

bI = sI .exp( bV

TV)

cI = bβIIb Ic

Vb Vc

bI = sI .exp( BV + AV cosωt

TV)

b,dcI = sI .exp( BV

TV). 0J ( AV

TV)

c,dcI = sβI .exp( BV

TV). 0J ( AV

TV)

DC currents under RF drive

Traditional biasing schemesConstant current bias: Ic,dc fixed, VB falls at increased RF powerConstant voltage bias: Ic,dc increases with RF power proportional to J0(VA/VT)

J0 : modified Bessel function of the first kind of order 0



Novel Biasing Scheme

M 1 M 2 M 3 M 4

X 1

I re f

n .I re f

X 2

I b a s e m .I b a s e

R 1m .R 1

C 1

C g d

C g s

C c o u p lin g

R F in

m n .I re f

R F C

P o w e r a m p li f ic a t io n d e v ic e

X1 is the replica device.X2 is the main device.M1 is for biasing the collector of the replica device to have n times Iref.M3 is for biasing the base of the replica device.M4 is scaled so that it biases m times of M3.The collector of X2 is therefore m.n times Iref.



Insensitivity to Process, Voltage, and Temperature

The Iref is generated from the bandgap voltage reference over an external resistor (not shown in schematic). Therefore, it is constant over the change of biasing voltage

Biasing currents are only dependent on the ratio of transistors,it is therefore insensitive to the process variation such as gm

and VT

The temperature dependent gm and VT do not have any role in this biasing scheme, so it does not change the biasing currents over the change of temperature



Simulation Results of Biasing Network

−40 −20 0 20 40 60 80 100466

468

470

472

474

476

Temperature (C)

Out

put s

tage

col

lect

or c

urre

nt (

mA

)

3.0v2.5v2.0v

−40 −20 0 20 40 60 80 100460

465

470

475

480

Temperature (C)

Out

put s

tage

col

lect

or c

urre

nt (

mA

)

FastTypicalSlow

Output Stage collector current fordifferent corners

LESS THAN 1.5% CHANGE OVERPROCESS VARIATION

Output Stage collector current fordifferent collector bias voltages

LESS THAN 1% CHANGE OVERTEMPERATURE



Low Temperature Co-fired Ceramic

Multilayer Ceramic Substrate

High-Q, Vertical Integration

Kyocera 10 Metal Layer Process

Output Network

λ/4 RF Shorted Stub → Even Harmonic Short

Harmonic Suppression Filter → Spurs, 3rd Harm

Single Stub for Match

Nearly Short at 2nd Harm and Open at 3rd Harm

-12-

LTCC Output Network-IntroductionPA Module-3D RF front-end-Future Goal


-60

-50

-40

-30

-20

-10

0

1 2 3 4 5 6 7 8Frequency (GHz)

> 40 dB Supp of 2nd/3rd Harmonics

< 1 dB Loss at Fundamental

Sharp Cutoff ⇒ Supp of Spurs

0

0.2

0.4

0.6

0.8

1

0

30

60

90

120

210

240

270

300

330

S11 with Zopt input and 50 ohm output termination

f02f0

3f0

Match/HSF

Zopt 50Ω

-14-

Performance of Output Network-IntroductionPA Module-3D RF front-end-Future Goal


SiGe HBT PAM with HSF

Semi-lumped low pass filter

Two finite attenuation poles

-13-

0.5”

0.75”



27 dBm Output Power at 0 dBm Input

45% PAE at Above35 dB linear gain

At 0 dBm input2nd harmonic: -44dBc3rd harmonic: -49dBc

-30

-20

-10

0

10

20

30

0

10

20

30

40

50

-15 -10 -5 0 5Input Power (dBm)

Pout (fundamental)

Pout (2nd harmonic)Pout (3rd harmonic)

Performance of the Power Amplifier-IntroductionPA Module-3D RF front-end-Future Goal


Demonstration of Silicon-Based Power Amplifiers

with Different level of Integration towards RF SOP

Integrated on chip with chip Passives

Integrated on chip with MEMS Passives

Integrated on Package

Fully Integrated on Package

-18-

Summary-IntroductionPA Module-3D RF front-end-Future Goal


• Compact RF Front-end Module for IEEE 802.11a WLAN

Applications

Motivation/Objectives

Demand for high data rates, broadband transmission

Significant RF interference within 2.4 GHz

802.11a more attractive for their high data rates in

densely populated area

Short coverage, more access points needed

Need for low cost RF front-end module

WLAN

IEEE 802.11b (2.4GHz)DSSS (Direct Sequence Spread Spectrum)Up to 11 Mbps data ratesLonger Range (200-300 feet)Significant RF Interference

IEEE 802.11g (2.4GHz)OFDM (Orthogonal Frequency Division Multiplexing)More than 20 Mbps data rates

IEEE 802.11a (5GHz)OFDMHigh throughput up to 54 MbpsShorter Range (100-150 feet) -> Need more access pointsDensely populated environment

-Introduction-PA Module3D RF front-end-Future Goal


System Architecture

Front-end MMIC0.6-µm GaAs MESFETSingle chip integration (LNA, PA, SW)

LTCC BPFDupont 943 TapeEmbedded folded coupled line structure

ANT

LTCC BPF

Front-End MMIC

PA

LNASW



LNA Design

D-mode FET : Better IMD performanceOptimum device size : 300µmCascode : High IIP3, Low dc powerInductive degeneration matching50 x 20 mil2Gain : 13 ~16.5 dBNF : 2.0 ~2.4 dBIIP3 : 2.8 dBm3V, 13.2mA



PA Design

2-stage Class-A Operation1.5mm & 2.4mm MESFETDynamic load line methodLow freq. stabilizing circuit100×40 mils2

Specification Measured DataOperating Frequency 5.1 GHz ~ 5.8 GHz

Power Gain 14~16 dBOutput P1dB 24 dBm

OIP3 41 dBmIM3 at P1dB > 25 dBc

Harmonics at P1dB > 28 dBcInput VSWR < 1.5 : 1



SW Design

SPDT configurationD-FET (-0.6Vp) : High P1dBDevice optimized for Insertion loss, Isolation

Series (1.2mm), Shunt (0.6mm)30 x 30 mils2

COMMON

FET1 FET2

FET3

FET4

V1 CTL

RF1 RF2

V2 CTL

Insertion Loss : 1.2 ~ 1.5 dBIsolation : 24 ~ 20 dBReturn Loss > 13 dBInput P1dB

28 dBm (Tx mode)26.5 dBm (Rx mode)



Filter Configuration

Multi-layer version of conventional filterEmbedded folded edge-coupled stripline3 ground plane connectedStripline to CPW transition

L

S

W

Port 1

Port 2

50 Ohm

50Ohm

Stripline Ground Plane

Ground Via

B



LTCC Filter Implementation

Port 1

Port 2

B

A

A'

Insertion Loss : 3.5 dB @ 5.8GHzReturn Loss : 15 dB @ 5.8GHzImage Rejection : 22 dB @ 5 GHz

Dupont 943AT Tapes• On-wafer testable• Stripline to CPW Transition • 20 Layers• εr = 7.5• Thickness : 4.4 mils

5.6 x 3.1 x 2.2 mm3



LTCC Front-end Module

MMIC on LTCC substrateBPF folded and embeddedMMIC can be mounted on the top of embedded BPF to save space8 x 9 x 2.2 mm2

BPFFront-endMMIC

SW LNA

PA

0.6-µm GaAs MESFET ProcessLNA : Cascode, Inductive degenerationPA : Class-A, 2-stageSW : SPDT, D-FET80 x 100 mil2



Rx/Tx Chain Measurements

Rx Chain

Overall gain : 11.5 dB @ 5.8GHz

Image Rejection : 27dBc @ 5GHz

IIP3 : 7 dBm

-20

-15

-10

-5

0

5

10

15

20

5 5.2 5.4 5.6 5.8 6

Frequency (GHz)

Filter_SW_LNA

LNA

SW_LNA

Tx ChainOverall gain : 11 dB @ 5.8GHzImage Rejection : 20dBc @ 5GHzOutput P1dB : 20 dBm

-10

-5

0

5

10

15

20

5 5.2 5.4 5.6 5.8 6

Frequency (GHz)

PA_SW_Filter

PA

PA_SW

0

2

4

6

8

10

12

14

16

10

12

14

16

18

20

22

24

26

Output P

1dB (dB

m)

PALNA SW BPF

Tx Mode

Rx Mode



Conclusions

Highly integrated, Broadband, High Linear Front-

end Single GaAs MESFET MMIC

Embedded 3-D LTCC-based BPF

Demonstrates the feasibility of on-package

integration of RF front-end system



ApplicationApplication

DesignDesign

PackagePackage

System partitioning

System partitioning

Spec.DefineSpec.

Define

ActiveDesignActiveDesign

EMSimulation

EMSimulation

OptimizeLayout

OptimizeLayout

MaterialMaterial

Thermal DesignThermal Design

Advanced RF Front-end Solution - SOP

Off Chip PassiveDesign

Off Chip PassiveDesign

Thermal DesignThermal Design

System Define

System Define

Wireless

Wired

Optica

lOpt

ical

Fibe

rFi

ber

Coppe

r

Coppe

r

Fixed wireless

Fixed wireless

Mobile wirelessMobile wireless

MobilityMobility

Ban

dwid

thB

andw

idth

SMF

MMF

DSL

Cable

Twist Pair

P-P Satellite linkPower

0.9GHz ~ 2.1GHz

P-MP

Communications by Channel

WAN

MAN

LAN

PAN

Mobile

10G10G

1G1G

100M100M

10M10M 1M1M

OC-192OC-192

OC-48OC-48

OC-768OC-768

PONPON

IEEE1394IEEE1394

DSLDSL

Cable modemCable modemIEEE802.16IEEE802.16

IEEE802.11a,b,gIEEE802.11a,b,g

IEEE802.3IEEE802.3

IEEE802.15IEEE802.15

W1394W1394

BluetoothBluetooth

3G Mobile3G Mobile

2.5G Mobile2.5G Mobile

Optical FiberOptical Fiber

CopperCopper

Fixed WirelessFixed Wireless

Mobile WirelessMobile Wireless

Research Direction

Next Generation Communicator

- Adaptive Physical Layer Concept -1-2 GHz

2-3 GHz

5-6 GHz

20 GHz

60 GHz

Channel

GSMGSM

WCDMAWCDMA

4G Cellular4G Cellular

WIEEE1394WIEEE1394

802.11bg802.11bg

BluetoothBluetooth

802.11a802.11a

NextG LANNextG LAN

Physical Layer

MACMAC

Adaptive Services

PositionVoiceData

InternetMultimedia

Adaptive Services

PositionVoiceData

InternetMultimedia

Future Work and Research Fund

NSF New Faculty Career Award

Research Program : NSF and DARPA

NSF(Sensor and Sensor Network)

High Speed RFIC for Wireless Sensor Network

DARPA(MTO): Wide Bandgap Semiconductor Technology

High Power Microwave Circuit

DARPA(MTO): Intelligent RF Front-End

Smart RFIC Module

DARPA(MTO): VLSI Photonics, Radio-Frequency Lightwave Integrated Circuits

Optical Transceiver

Radio on Fiber

Fund from Industry : NSC, IBM, SAMSUNG, LG, CREE

Thank you for your Attention

Deuk Hyoun Heo, Ph.D.

[email protected]

Communications by Standards

WAN (Core network : Backbone)OC-48(2.5G)-> OC-192(10G)-> OC-764(40G)

MAN (Access network : Last mile)Passive Optical Network (FTTH) : Fiber ~155MbpsDSL, Cable modem (FTTC) : Copper ~10 MbpsIEEE1394 (Fiber/Copper) : 100, 200, 400MbpsWireless MAN: IEEE802.16 (10-60GHz , 802.16.a(2-11GHz) ~100Mbps

LANEthernet : IEEE802.03, GbEWireless LAN : 802.11a(~54Mbps, 5.8GHz), b(~11Mbps, 2.4GHz), g(~22Mbps, 2.4GHz), HIPERLAN/2 (5~6 GHz)

PAN (In Home Network)Wireless PAN 802.15: 802.15.3(~55Mbps, 2.4GHz), 802.15.4(~1Mbps,800MHz)Wireless IEEE1394 (54~100Mbps, 5/20/60GHz) Bluetooth (~1Mbps, 2.4GHz)

Mobile communication (Cellular Network)2G: GSM-> 2.5G: GPRS-> 3G: WCDMA (~2Mbps)2G: IS-95-> 2.5G: IS-95B-> 3G: CDMA2000 (~2Mbps)

Next Generation Communication

• Main stream : DWDM and 40Gbps• More optics : toward all optic network• Alternative solution with higher spectral efficiency.

– Channel coding : Block code to convolution code – Modulation (OSCM, QAM) – Advanced multiplexing (OCDMA, OTDM)

• More fiber (BW) • More wireless (Flexibility) • Copper won’t die for a while (Cost) • Opto/RF hybrid comm. will get more attention • Some of PAN will die or be merged

• Main stream : Merging of Data and Voice Comm• Maximize data rate for the given channel : OFDM, CDMA• Adaptive physical layer and soft handoff at MAC layer• Seamless integration in single platform • Higher frequency for more BW• Flexible service (Internet, Voice, Multimedia, Game …)

Backbone

Last mile

Wireless Data/mobileComm.

Example : 60GHz WLAN

Optical Analog TRX

Wideband Direct Up-Conversion

Injection Locked VCO

60 GHz Front-end

OFDMMODEM

I/QMOD

3GHz/4 GHz

MZ-MOD

7GHz/14 GHz

7/10GHz

3/4GHz

High Quality VCO

TIA

Phase Injection-

Locked VCO

Linear PA

Fc=7/14GHz

Fc=7/14GHz 7/10G

Hz

Fc=3/4GHz

Sub-harmonic

Mixer

3/4GHz60GHzAntenna

Antenna

RXM

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