RF DEVICE TESTING FOR MOBILE 두식이사(TERADYNE).pdf · PDF fileSkyworks 77352- 15 GSM/GPRS/EDGE ... Avago AFEM-7813 dual-band LTE B1/B3 ... Modulated Jammer Out of band blocking

RF DEVICE TESTING FOR MOBILE DEVICES

Korea Test Conference workshop 2015

Dusik YooSenior RF Applications Engineer

[email protected]

• Wireless Industry Trends

• RF Transceiver block diagram

• RF Transceiver Test Items

Contents

Smartphone & Tablet Continuing to Grow Worldwide• Units increasing by 340M units to 2.45B annually by 2018• Companies releasing 2x - 3x more new designs annually to meet

both premium & basic smart phone demands• Handset ASP shrinking by >5% YoY

Wireless Industry Trends

• Increase Demand for Higher Data Rate & Connectivity• Overall mobile data traffic is expected to grow at a 61% CAGR to 15.9

Exabytes per month by 2018• Migration to LTE-Advanced occurring in all market segment (high and low end)• New standards require 2x-3x more active RF device ports• Expanded use of licensed and unlicensed Frequency bands• Demand for higher performance and high site count test capability


• Embedded sensors capable of exchanging data wirelessly• Internet-of-things driving rapid growth of MCU + RF segment• Wearable consumer products dominate unit volumes• Infrastructure shifting to wireless monitoring and control• Introduction of RF into predominantly digital consumer

devices, results in down pressure on RF costs• Increasing device complexity

• Shrinking Device Size While Increasing Complexity• Mobile IC’s moving away from

conventional package to wafer-level package technologies (Flip-chip, WLCSP, FOWLP)


18B connected devices by 2018

>50% IoT devices

• RF devices are more complex • Introduction of RF into predominantly digital consumer devices• 2x~4x increase in receive/transmit ports• Most smart phones need to support multiple bands -> LTE-A, LTE, CDMA,

HSPA+, GSM Generates lot more data streams • Higher bandwidths (up to 100MHz) and faster data rates(up to 1Gbps)• Support new technologies such as MIMO and Carrier Aggregation

• ATE Capabilities• Need for adequate RF Instrument Performance • Need for complex signal analysis toos (EVM rms/peak, frequency error, …)

Increasing RF Test Complexity

16x Increase

• DSP computation times will increase substantially • Increasing data due to wider bandwidths, complex demodulation schemes and

EVM calculations has to be processed• Increased DSP computation time will drive up test times

• ATE Capabilities• Transparent transfer of large amount of data• DSP computation power for complex modulation tests• DSP subsystem that scales multisite (>x8)

Increasing RF Test Complexity – DSP

4x Increase

Higher Bandwidth

• Requirements• Higher data rates requires additional higher frequency

modulation signals• Instruments must have very high accuracy and low noise

and distortion at high frequencies• Multiple pins of AWG and Digitizer must have very low skew

• ATE Capabilities• Need excellent AC specs cover 100MHz• Need minimum AC skew between AC pins

LTE-Advanced Maximum Bandwidth5 x 20MHz

Carrier 1 Carrier 2 Carrier 3 Carrier 4 Carrier 5

20MHz 20MHz 20MHz 20MHz 20MHz

Current LTE Bandwidth1 x 20MHz

Carrier 1

20MHz

Source 1

Source 2

Very precise phase

Very Precise Amplitude

Data waveforms

Native Tester Performance. No User Calibration Required

0

1

2

3

4

5

6

7

0 25 50 75 100

125

150

175

200

225

250

275

300

325

350

375

400

425

450

475

500

% E

VM

I and Q Timing Skew effects on EVM

802.11ac 160M 256QAMLTE-Adv 100M 64 QAM802.11ac 80M 256QAM802.11ac 80M QPSK802.11ac 40M 256QAMLTE 20M 64QAM

802.11ac 160MEVM Limit = 2.51%

Example of How Tester Errors Become More Critical for New RF Standards

The plot below shows the effects of IQ skew Imbalances (modulation signals being out of phase). If testing an actual device, the skew, gain and other impairments would contribute to the EVM error.

LTE 20M

LTE-A 100M

Skew

11ac 80M (100ps Skew = 1-2% EVM)

802.11ac 160M

11ac 80M (25ps Skew = 0.5% EVM)

LTE-A 100M (200ps Skew = 2-3% EVM)

• Stand-alone txcvr (RF to AC/Dig IQ) paired with a separate PMIC & baseband

• High-end SmartphonesCellular Txcvr

• Multi-standard connectivity SOC (BT, WLAN, NFC, etc)• Cellular handsets and tablets, PC

Complex Connectivity

• Combined BB+RF in either SOC or SIP• Low-to-mid cost SmartphonesCellular SOC

• Single standard connectivity ICs• Mobile phone accessories, wireless keyboard/mouse/remote

control, wearable sensors, personal health monitors

Discrete Connectivity

• Traditional MCU (typicallly 8-16bit) with simple connectivity in either an SOC or SIP

• White goods, smart power, industrial controls, security systemsMCU+RF

• Front-end RF ICs that are RF-RF connecting antenna to cellular or connectivity radio

• Mobile handsets, tablets, PCsPA/FEM

Wireless Device Segment Definitions

• “Test” is no longer just seeing if a part is good or bad

• It is part of the manufacturing process

• Trimming/calibrating• Grading for speed, Accuracy, etc.

• In many cases, many devices would have zero yield if they didn’t go through the trimming/calibration process

• This is a major contributor to cost of “test” that is increasing and needs some process/DFT or technology change

“Test” now includes more functions

This time not really “test” time. It is used to finish

“making” the device


• Transceiver block diagram


Contents

Mobile Phone teardown

Skyworks 77352-15 GSM/GPRS/EDGE Power Amplifier Module

Skyworks SWUA 147 228 RF antenna switch module

Triquint 666083-1229 WCDMA / HSUPA Power Amplifier / duplexer module for the UMTS band

Avago AFEM-7813 dual-band LTE B1/B3 Power Amplifier+FBAR duplexer module

Skyworks 77491-158 CDMAPower Amplifier Module

Avago A5613 ACPM-5613 LTE band 13 Power Amplifier

Qualcomm PM8018 RF Power Management IC

Hynix H2JTDG2MBR 128 GbNAND flash (16 GB)

Murata 339S0171 Wi-Fi module (BRCM 4334) 802.11 a/b/g/n, BT 4.0, FM (Connectivity Combo IC)

(Dialog) Apple 338S1131Power management IC

Elpida 338S1117 or SanDisk SDMALBB4 Memory MCP STMicroelectronics L3G4200D (AGD5/2235/G8SBI )

Low-power three-axis gyroscope

Apple A6Application Processor

STMicroelectronics LIS331DLH (2233/DSH/GFGHA) Ultra low-power, high performance, three-axis linear accelerometer

Texas Instruments 27C245I Touch Screen SOC

Broadcom BCM5976 Touchscreen Controller

Qualcomm MDM9615M LTE Baseband modem

Qualcomm RTR8600 Multi-band/mode RF transceiver / GPS

Photo Credit: iFixit

Mobile Phone Front End Block

Photo Credit: Techinsights

Crystal or TCXO

Rx PLL ~

I

QADC

I

QD

own

Converter

RX_Band_IRX_Band_IIRX_Band_VIRX_Band_VIII

Primary RX

Diversity RX

Dow

nC

onverter

TX_Band_VIII

I

Q

I

Q

I

QDAC

I

Q

TX_Band_ITX_Band_IITX_Band_VI

Tx PLL ~

SPIDCXO

orTCXO

RX_Band_IRX_Band_IIRX_Band_VIRX_Band_VIII

……

…

ADC

IQTo Analog BB

IQTo Analog BB

IQFrom Analog BB

DUT Control

RX_Band_IXRX_Band_XI

RX_Band_IXRX_Band_XI

TX_Band_XITX_Band_IX

TxM

odulator

Page 15

RF (Rx)Microwave Source

RF (Tx)Microwave capture

Analog (Rx)Capture

Analog (TX)Source

Analog (Rx)Capture

PowerDC Bias

Digital Protocol

Transceiver Block Diagram & ATE Resource

DUTCLK

Contents


• Transceiver block diagram


Cellular Test Lists

• GSM / EDGE– RF Power– Power vs Time– Frequency Error– Phase Error– EVM– IQ Offset– Mod / Switching

ORFS– RSSI

• W-CDMA‒ RF Power‒ Frequency Error‒ Occupied Bandwidth‒ ACLR‒ EVM‒ IQ Offset‒ RSSI

• LTE / LTE-A‒ RF Power‒ Frequency Error‒ EVM‒ In-band Emission‒ IQ Offset‒ Spectrum Flatness‒ Occupied Bandwidth‒ ACLR‒ RSSI

• CDMA2000 / EV-DO‒ RF Power‒ Frequency Error‒ Time Reference Error‒ Mod Accuracy‒ Cond. Spur. Emission‒ ACPR‒ IQ offset‒ Occupied Bandwidth‒ RSSI

• Transceivers consist of transmitter and receiver

• Receivers and Transmitters are frequency-translating devices

• Can be divided into five categories•RF to RF (LNA, PA)•BB to RF (Transmitter)•RF to BB (Receiver)•PLL/VCO•RF to Digital (BER/FER)

RF in RF out

RF to RF DUT

RF Transceiver Device

TX ITX Q PA

RX IRX Q I/Q Demodulator LNA

RF Out

RF In

TX Synth

RX Synth

I/Q Modulator

BB to RF

RF to BB

Testing Transceivers on the ATE

LTE / LTE-A Typical RF Test List

Transmitter TestsOutput power (Max, Min)Carrier suppression & Image suppressionGain ControlEVM (Uplink)Spectral MaskOutput SpursVCO Output (Phase Noise)Adjacent channel leakage ratio (ACLR)

Receive TestsGain / P1dBSensitivity : Noise FigureReceive Blocking Tests: Modulated Jammer Out of band blocking CW Jammer

Receive Filter FlatnessAmplitude / Phase ErrorIntermodulationEVM (Downlink) DC offset

RX Test : Gain (Power measurement)

• Gain is the most basic performance characteristic of an amplifier.

• In the RF and microwave world, gain is usually specified as a power gain instead of a voltage gain.

• Power Gain, G, is the ratio of power delivered to the load to the power delivered by the source (only affected by load match).

• Gain is also measured as S21 (in a 50W environment).

G (dB) = 10 LogPout (mW)

Pin (mW)= Pout (dBm) – P in (dBm)

RF in RF outRF to RF DUT

Microwave Source Instrument

Microwave Capture Instrument

f1

Ampl

itude

f1

Ampl

itude

Dynamic Range

• ATE has superior dynamic range•Less averaging•Better accuracy•Higher throughput•Lower COT

• ATE Specifications•Instantaneous Dynamic Range: > ? dB•Spurious Free Dynamic Range: > ? dB

Spurious Free dynamic Range

Maximum IMD

Average Noise Floor

Instantaneous dynamic Range

Max Power w/ 0dB atten.

Measurement Uncertainty Error Vs. Signal/Noise Ratio

-2.00

-1.00

0.00

1.00

2.00

0 5 10 15 20 25 30 35 40 45 50 55 60

S/N delta (dB)

Mea

sure

men

t Err

or (d

B)

RX Test : P1dB

Power output at 1dB compression point

P1dB=13 dBm 1dB

Slope=1

RX Test : IP3Linearity and Non-Linearity

Linear Operation

x1(t) y1(t) y1(t)= a+bx1 (t)x2(t) y2(t) a

Linear System

ax1(t) + bx2(t) ay1(t) + by2(t)

all value of the constants a and bAny system that does not satisfy this condition is Nonlinear.

ex) y(t) = α0 + α1x(t) + α2x2(t) + α3x3(t) + …

• Linearity

• Linear System

• Why linearity is important?RF system is nonlinear system: Amp, Mixer, Oscillator,…. Harmonics, Intermodulation Distortion,..

Frequency Resource limitation

DC Fundamental Harmonics

Frequency

f

2f3f 4f 5f

Fundamental frequency

Am

plitu

de

• Consider what happens if the input voltage waveform to a DUT is a single tone frequency,

vin = Acos(ωt)• Then the fundamental equation becomes

• The cosine powers can be transformed into:

...coscoscos 333

22210 ++++= tAatAatAaavout ωωω

tAatAatAaAaAaavout ωωω 3cos4

2cos2

cos)4

3(2

33

22

33

1

22

0 +++++=

NonLinearOperation

Frequency

f

Am

plitu

de

RX Test : IP3Effects of Non Linearity : Harmonic Distortion

• Consider what happens if the input voltage waveform to a DUT is a two tone frequency,

vin = Acos(ω1t) + Bcos(ω2t)

• Then the fundamental equation becomes

• Second- order Intermodulation

22122110 )tcosBtcosA(a)tcosBtcosA(aavout ωωωω ++++= ...)tcosBtcosA(a +++ 3

213 ωω

x

twwcABtwwcABtwcBtwcABAc

twBtwwABtwwABtwAa

twBtwtwABtwAa

)cos()cos(2cos2

2cos2

)(2

)2

2cos1)cos()cos(2

2cos1(

)coscoscos2cos(

21212

2

1

222

222121

122

222

21122

2

−++++++=

++−+++

+=

++=Next page

Harmonic Freq 2nd Order IMD

NonLinearOperation ...)()()( 3

32

210 ++++ txatxatxaa

RX Test : IP3Effects of Non Linearity : Intermodulation Distortion

• Third- order Intermodulation

twwdABtwwBdA

twwdABtwwBdAwdBwdA

twdBBdAtwdABdA

twBtwAa

)2cos(4

3)2cos(4

3

)2cos(4

3)2cos(4

33cos4

3cos4

3

cos)2

34

3(cos)2

34

3(

^^....^^........^......^)coscos(

12

2

21

2

21

2

21

2

2

3

1

3

2

32

1

23

3213

−+−+

++++++

+++=

−−−=+

Harmonic Freq

3rd Order IMD

RX Test : IP3Effects of Non Linearity : Intermodulation Distortion

• Why Intermodulation Distortion is important?

• Generally: fout = mf1 ± nf2

• Third-order products fall in-band (can't filter)

• Measured in dBc or as TOI (Third-Order Intercept Point)

• ex) 900MHz , 901MHZ and 902MHz2f1 - f2 = 2*901 – 902 = 900

In-bandDUT

f1

Ampl

itude

f2 f1Am

plitu

def2

2f2 - f12f1 – f2

RX Test : IP3Intermodulation Distortion: Order

RX Test : IP3 (Third Order Intercept Point)

)21

23

22P33

21

23

)21213

IM

IMFundININ

IMFundFund

Fund

IMFund

IMFundFund

Fund

P(PPIMDPIIP

PPPPOIP

PP

P(PP

IMDPOIP

−+=+=∴

−+=

−=∴

−=

−+=

+=OIP3

IIP3INP

IMP

FUNDP 2IMD

2IMD

IMD

1m =

3m =

• The device’s IP3 is a theoretical point where the power in the fundamental would be equal to the power in the intermodulation product.

• The intermod products rise 3dB for each 1dB increase in fundamental power.• The IP3 point is never reached because the device goes into compression.

GOIPIIP −= 33

• The IP3 of an LNA is calculated below.

• Notice that the term dBc is used.

• OIP3 = -20dBm + (46dBc/2) = +3dBm

• If the intermodulation products were lower (better) then, for example, using IMD=56dBc, OIP3 = +8dBm

IP3 calculation Example

RX Test : IP3

• The intermodulation distortion product performance of the tester RF sources must not contribute to the measurement

• ATE Source Intermodulation distortion (SIMD)

• SIMD (3rd order) of Tester : < -?? dBc

• Source IP3 : > ?? dBm

Receiver System

Small Signal Imperfect Amplifier

Signal Larger,But Noiser

RX Test : Noise Figure

• Why Noise is important?

• High Frequency Noise1. Thermal (Johnson or Nyquist) noise

Thermal vibration of bound charges.2. Shot noise

Random fluctuations of charge carriers.

• Low Frequency Noise1. Flicker (1/f) noise

Noise power varies inversely with frequency.


• Noise Source

HzdBmHzmWHzW

XX L

/174/104/104kT

C 17 temproom :K)290(T eTemperatur StandardAt K)(290 eTemperatur Reference T

)Kelvinjoules10*(1.381Constant Boltzmann k (Hz)Bandwidth B

,RR i.e. Load, Conjugate a toDeliveredPower kTBP

18-21-O

OO

O

23-

Lav

−=×=×=

°=

=

=

=====

* Nyquist and Johnson’s theory•Available Noise Power(Thermal)

LL jXR −jXR +


))()((

)()log(*10:

)/()/(

:

)()()()(

)()(

)(

)(

dBNoiseOutdBRFOutdBNoiseIndBRFIn

dBoutdBin

noiseoutrfout

noiseinrfin

dBout

dBin

PPPPNFSNRSNRFNFFigureNoise

PPPP

SNRSNR

FFactorNoise

−−−=

−==

==

Noise figure is a measurement of the amount of noise which is added by a device. The Noise Factor is represented by the symbol F:

dBSNRin 10=dBNF 3=

dBSNRout 7=


KTTo

oa

KTTin

ina

in

out

in

out

out

in

out

in

oa

oa

GBKTGBKTN

GNGNN

NN

GNN

SS

NSNSF

FigureNoise

290

290

)()(

1)()(

)()(

)/()/(

:

==

==

+=

+====

Na, Goutin

IRE

f1 f2

Nin*Ga

Noise Added Na

Nout

( ))BG(FkTNote:N

KregistanceSourceofeTemperaturTBandwidthBGain,AvailableG

BkTi.e.,NKatWhenSourcetheFromPN

Where

oa

o

oin

avin

1290

290

−==

===

=

• An Equivalent Definition of Noise Figure

oaout KGBTNN +=


Na, Ga

outN

ss TZ @

saouta

saa

ainaout

BTkGNN

BTkGNGNNN

−=

+=

+=

CT0

HT

aN

CN

HN

Noi

se O

utpu

t Pow

er (W

)

Temperature of Source Impedance (K) ST

CH

CHa TT

NNBkGslope−−

==

BGkTN

GNN

GNNF

o

a

in

a

in

OUT BGkTGN oin +=

+==

FdB log10)(NF =

slope

• Noise Power is Linear with Temperature

Input NoiseAdded Noise


• The Y-Factor method of measuring NF uses a noise source applied to the input of the DUT to supply two different noise power levels to the DUT

• Power measurements over as specified bandwidth are made at the DUT for each of the two applied noise power levels

• The Y-factor is defined as:

• The Y-Factor can also be expressed in dB.Y|dB = Pmeasured,hot|dB – Pmeasured,cold|dB

coldmeasured

hotmeasured

PP

Y,

,=

TesterNoise SourceON

DUT

Noise SourceOFF (50 ohms)

TesterDUT

Step 1 (hot noise power measurement)

Step 2 (cold noise power measurement)

• Y-Factor Method of Measuring NF


• A property of the noise source, termed Excess Noise Ratio, or ENR is defined for every noise source.

• Ratio of the noise power of the noise source when turned on, compared to the power of the noise source at a reference temperature (typically taken to be T=290K)

• ENR is used with the Y-Factor to calculate Noise Factor

• F = ENR/(Y-1)

• and then NF = 10log10F TesterNoise SourceON

DUT

Noise SourceOFF (50 ohms)

TesterDUT

Step 1 (hot noise power measurement)

Step 2 (cold noise power measurement)

• Y-Factor Method of Measuring NF


DUT

Tc

RF

LO

BBLNA AGC

DGT dBdB GNNF −+= 1740

• The Direct Noise Measurement• Does not require a noise source• Only need a 50 ohm termination to the input of the DUT

• Cold Noise Method of Measuring NF

50ohm


• If DUT Gain is “large” enough, neglect the ATE noise figure influence. • Then, from the fundamental definition of noise figure,

• Put into dB,

• NF|dB = Pmeasured,cold|dBm – (-174 dBm/Hz) – 10log10(B)|Hz – G|dB

−+=

1

21

1G

FFFsysATE DUT NF1GainNF2

BGkTPNo

FF coldmeasuredsysDUT

0

@ )(==≈

GBTKNNF −−−−= 00

• Cold Noise Method of Measuring NF


• Advantages of Each Method • Y-Factor method uses relative power measurements so

absolute power accuracy does not skew correlation• Cold Noise method is easy to implement from an ATE hardware

point of view


• Cascaded Noise Figure (Friis’ equation):

• The total Noise Factor is not dependent on the gain of the final stage.• The Noise Factor of the first stage is usually the most dominant. • The Noise Factors of the subsequent stages do add to the total noise factor but

are diminished by the gains of the preceding stages.• For this reason it is often necessary to make adjustments based on the Noise

Factor of the measurement system if it is significant and the DUT gain is low.

−+===

−+=

+=

++=

1

21

21

1

21

1)(/

/

,1

eForPerStag,Use

GFF

BkTGGN

NSNSF

GFFGBGkTN

GNGNNF

,GBGkTGNNN

o

o

oo

iisys

210o

i

ia

2102a1a2o

12121

3

1

21

111

−

−+

−+

−+=

n

nsys GGG

FGG

FG

FFF

For N Stage,


RF

LO

IFLNA

Why Receiver Need LNA ?

12121

3

1

21

111

−

−+

−+

−+=

n

nsys GGG

FGG

FG

FFF

For N Stage,

IF Amp

12121

3

1

21

111

−

−+

−+

−+≈

n

nsys GGG

FGG

FG

FFF

If LNA Gain is High Enough,


• Cascaded Noise Figure Example• Consider the following two RF system configurations:

• Using Friis’ equation, calculate the total cascaded Noise Figure of each system………………

input

FTotal F1=F2 1–

G1a---------------

F3 1–

G1aG2a----------------------+ +

output

Amplifier2G = 12dB

NF = 7

Amplifier1G = 16dB

NF = 2

3dB padGain = -3dB

NF = 3dB

input output

Amplifier2G = 12dB

NF = 7

3dB padGain = -3dB

NF = 3dB

Amplifier1G = 16dB

NF = 2

Configuration 1

Configuration 2


F=Noise FactorNF = Noise Figure(dB)

• Cascaded Noise Figure Example:

• This is why the Low-Noise-Amplifier should always appear as close as possible to the receiver front end in a system design.

NF 10 F( )log 10 2 1.6 1–0.5

---------------- 5 1–0.5( ) 39.8( )----------------------------+ +

log 5.31dB= = =

NF 10 F( )log 10 1.6 2 1–39.8------------ 5 1–

0.5( ) 39.8( )----------------------------+ + log 2.61dB= = =

input output

Amplifier2G = 12dB

NF = 7dB

Amplifier1G = 16dB

NF = 2dB

3dB padGain = -3dB

NF = 3dB

input output

Amplifier2G = 12dBNF = 7dB

3dB padGain = -3dB

NF = 3dB

Amplifier1G = 16dB

NF = 2dB

Configuration 1

Configuration 2

2a1a

3

1a

21 Total GG

1FG

1FF −+

−+=F


F=Noise FactorNF = Noise Figure(dB)

RX Test : Amplitude / Phase Balance

• The purpose of this test is to evaluate the difference between the magnitude and phases of the signals coming out of the DUT baseband (I and Q) pins.

• A cw RF signal is applied to the DUT and baseband (I and Q) magnitude and phase balance are measured. Afterwards, the figure of merit, Residual Sideband (RSB) is calculated from these two balance values.

I out

Q out

RF in

RFtoBB DUT

RX Test : Gain De-sense (Jammer Test)

• The purpose of this test is to ensure that the presence of a relatively high power level jammer signal does not impact the desired DUT gain.

• Apply RF single tone at nominal power level along with a cwjammer tone. At baseband (I and Q) measure and calculate gain and confirm that it isn’t affected by the presence of the jammer.

I out

Q out

RF in

RFtoBB DUT

f1

Ampl

itude

RF

fjam fB

Ampl

itude

Baseband

fjam

TX Test : ACLRSpectrum Growth Caused by IM3

frequency

Lower Adjacent Channel

Upper AdjacentChannel

Carrier Channel

TX Test : ACLR

SignalOut-Band Sidelope

IMD Adjacent channel

• Spectrum Re-growth with IMD Relationship

frequencyoffsetatpowerbandwidthMhzpowerchannelMhzACLR

_____84.3__84.3

=

freq+5MHz

3.84MHz

WCDMA modulated output signal

2100MHz-5MHz

3.84MHz3.84MHz

CDMA IS-95 W-CDMA

Main channel BW 1.23Mhz or 1.25Mhz 3.84Mhz

Adj. channel location ± 885Khz ± 5Mhz

Adj. channel location ± 1.98Mhz ± 10Mhz

Adj. channel BW 30kHz 3.84Mhz

• CDMA & WCDMA

TX Test : ACLR

TX Test : ACLR

• LTE ACLR requirements are specified for the following scenarios:• E-UTRA ACLR is the adjacent LTE channel• UTRA ACLR1 is the adjacent WCDMA channel• UTRA ACLR2 is the alternate WCDMA channel

Example of LTE 20MHz bandwidth ACLR Measurement

SignalMeasure BW: 18MHz

Offset: 0MHz

E-UTRA UpperMeasure BW: 18MHz

Offset: +20MHz

UTRA Adjacent UpperMeasure BW: 3.84MHz

Offset: +12.5MHz

UTRA Alternate UpperMeasure BW: 3.84MHz

Offset: +17.5MHz

UTRA Adjacent LowerMeasure BW: 3.84MHz

Offset: -12.5MHz

UTRA Alternate LowerMeasure BW: 3.84MHz

Offset: -17.5MHz

E-UTRA LowerMeasure BW: 18MHz

Offset: -20MHz

58MHz Bandwidth required

TX Test : ACLR Frequency offsets

Signal Properties

Phase, Φ

[radians]

Amplitude, A[Watts or dBm]

Frequency: f=1/TAngular Frequency: ω=2πf

amplitude

time

A

Period, T

• AC signal changes with time (e.g., sine wave)

• Amplitude, frequency, and phase can be altered

• Changes in these parameters at regular intervals in the signal can be used to represent information (modulation)

)sin()( φ+= wtAtV

Types of Digital Modulation

• 3 basic types of modulation with a binary sequence of 1’s and 0’s as the modulating signal

• Magnitude is an absolute value• Phase is relative to a reference signal

Phase0 deg

Polar Display - Magnitude and Phase Represented Together

0 deg

"I"

"Q"

{Q-Value

{I-Value

• Polar to Rectangular Conversion:

Project the signalon to “I” and“Q” axes

Polar to "I-Q" Format

I = In Phase Q = Quadrature

Magnitude Change Phase Change

Frequency ChangeBoth Change

Phase 0 degPhase

0 deg

0 deg0 deg

Signal Changes or Modifications in Polar Form

I and Q in a Radio Transmitter

• When Testing an RF Device, we want to measure how much the signal is corrupted by things like:

• Phase Noise• Signal Imbalance• Other noise and distortion

• All of these errors are combined into Error Vector Magnitude. It is a clear way to measure RF signal quality

• To do production testing, the EVM of the tester must be much better than the Device Under Test

Ideal Signal

Measured Signal

Test Limit

LTE BS = 13.5%LTE UE 12.5%802.11ac = 11.22%

LTE BS = 9.0%802.11ac = 3.98% 802.11ac = 2.51%

16-QAM802.11a/g, LTE

64-QAM802.11a/g/n; LTE-A

128-QAM802.11 ac

- ATE EVM measurement accuracy

Modulation Quality : EVM

EVM Sources

• Interference

• Phase Noise (VCO)

• Non-linearity distortion (PA, Mixer,AGC, A/D, D/A…)

• Modulation Error (BB: Equalizer Error, Freq. Offset…)

• Linear distortion (Filter: Freq. response, Group Delay)

• I/Q Mismatch (I/Q Modulator)

EVM source – I/Q Mismatch

• IQ Modulator

EVM source type

“VCO Phase noise”“Outband Signal Interference”

“System Noise”

ATE ESA Toolkit uses Agilent’s standard 89600 VSA for demodulation/spectral analysis

Benefits Get the latest RF standards sooner Accelerate bench-to-ATE correlation Reduce cost of test (test time) with Background DSP Improve test coverage (EVM)

20+ Wireless Standards Supported• GSM

• WCDMA• WCDMA-HSDPA/HSUPA• TD-SCDMA

• Bluetooth 1.2• Bluetooth 2.1+EDR, 3.0• DECT• 802.11a/g• 802.11b

• EDGE• CDMA• CDMA2000• 1xEV-D0

• 802.11n• 802.15.4 Zigbee• 802.11ac

• 802.16-2004 WiMax fixed• 802.16e WiMax mobile• Wibro• DVB-T• DVB-H• FM• RFID

Conn

ectiv

ityW

iMax

/D

ig B

road

cast

3G2G

• 3GPP LTE-FDD • 3GPP LTE-TDD

4G/L

TE

Modulation Signal Generation & Analyzer

ATE Setup for EVM Test

TX ITX Q PA

RX IRX Q I/Q Demodulator LNA

Key instrument specs:• I/Q Skew• Imbalance

Key instrument specs:• native EVM performance for 64QAM / 256QAM 20MHz LTE

Example LTE RFIC with Analog I/Q

RF Out

RF In

ACLR testEVM test

Analog Source

Analog Capture

UltraWave Capture

UltraWave SourceKey instrument specs:• Lower residual intermodulation in the LTE-Advanced bands• Tighter source accuracy down to

-90dBm• ACLR/EVM

Key instrument specs:• noise density

ATE performance have to enable full characterization of LTE-Advanced device and guarantee full test coverage in production for zero-defect.

TX Synth

RX Synth

I/Q Modulator

Page 64

I/Q Skew and Imbalance of the AC instrument directly impact the device EVM performance

• Based on a cross section of ATE applications released to production• Note that effective test time / site is influenced by device functionality

as well as system configuration, test list, and test methodologies

Test Time Performance Ranges

Device Type Sites Test Time PTE Test Time / Site

4G LTE Transceivers 4-8 8.6s – 10.3s 86% - 90%

3G Transceivers 4-8 2.3s – 6.6s 90% - 95%

2G RF SOC 4-8 5.9s – 16s 90% - 92%

Combos (BT/WLAN/FM) 4-8 9.0s – 11s 90% - 95%

WLAN .11n MIMO 4-8 5.9s – 9.7s 85% - 92%

WLAN b/g 8 3.0s – 4.2s 91% - 97%

BT 8-16 2.2s – 12s 90% - 97%

Power Management 4-8 0.9s – 3.1s 90% - 95%

1.5s1.0s0.5s

1.5s1.0s0.5s

4s3s2s

3s2s1s

3s2s1s

1.5s1.0s0.5s

3s2s1s

3.0s2.0s1.0s

Questions

Documents

RF DEVICE TESTING FOR MOBILE 두식이사(TERADYNE).pdf · PDF fileSkyworks 77352- 15 GSM/GPRS/EDGE ... Avago AFEM-7813 dual-band LTE B1/B3 ... Modulated Jammer Out of band blocking