Pim x Tim by Anritsu

8/9/2019 Pim x Tim by Anritsu

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Presented by Roberto Diana

Gennaio 2014

Understanding PIM and its effects

on network performance

Fundamentals of antenna andcable analysis


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Agenda I

Understanding PIM

Fundamentals and root causes of Passive Intermodulation (PIM)

Intermodulation possibilities in real world scenarios

Active versus Passive Intermodulation

Non-Linear Diode effect at solid state materials

Non-Linear Diode effect at ferromagnetic materials

Intermodulation mathematicsPIM and its dependence on used modulation scheme

PIM calculator

Why is PIM nowadays a problem

What is the goal of PIM fixing

How is PIM measured

PIM impact on other wireless services

PIM root causes


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Agenda II

Understanding PIM

How does PIM look like under real field conditions

Field Examples

Self made PIM sources

PIM indicators in cellular networks

PIM of connector assemblies

PIM Sources within RF interconnections

PIM in Distributed Antenna Systems (DAS)

What is the correct frequency to test PIM?

PIM measurements

PIM versus time

Distance To PIM (DTP)Swept PIM


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Agenda III

Understanding PIM

Guidelines and recommendations

Line Sweep Test (RL, DTF) versus DTP

PIM Master product concept

General function principle of PIM measurements

General function principle of PIM Master MW82119A

Summary

PIM measurements in Distributed Antenna Systems (DAS)

Practical demonstration of PIM measurements


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Intermodulation Possibilities


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Intermodulation

Root Causes for Intermodulation


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Intermodulation

Intermodulation is caused when 2

or more RF carriers are mixed in

an active system and form

unwanted signals

When passive components

containing non-linear elementsthose are the source of this

interference

we refer it in this case as

Passive InterModulation (PIM)

Active versus Passive Intermodulation


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Intermodulation

Non-Linear Diode Effectat passive ferromagnetic metals

How does it work in

passive components ?

A low signal operating in a

linear region and a large signal

operating in the non-linear

region of a ferromagnetic metalis creating additional spectral

components in the output

signal.

B [T]

H [Am-

1]


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Intermodulation

Intermodulation mathematics

Order Frequencies Tone 1 Tone 2

1st Order f 1

f2

100 MHz 101 MHz

2nd Order f 1+f2 f2+f1 201 MHz 1 MHz

3rd Order 2f 1-f

22f

2-f

199 MHz 102 MHz

2f1+f

22f

2+f

1301 MHz 302 MHz

4th Order 2f 2+2f

12f

2-2f

1402 MHz 2 MHz

5th Order 3f 1-2f

23f

2-2f

198 MHZ 103 MHz

3f1+2f2 3f2+2f1 502 MHz 503 MHz

7th Order 4f 1-3f

24f

2-3f

197 MHz 104 MHz

4f1+3f

24f

2+3f

1

9th Order 5f 1-4f2 5f2-4f1 96 MHz 105 MHz

5f1+4f

24f

2+3f

1

e.t.c.

Order Frequencies Tone 1 Tone 2

1st Order f 1

f2

100 MHz 101 MHz

2nd Order f 1+f2 f2+f1 201 MHz 1 MHz

3rd Order 2f 1-f

22f

2-f

199 MHz 102 MHz

2f1+f

22f

2+f

1301 MHz 302 MHz

4th Order 2f 2+2f

12f

2-2f

1402 MHz 2 MHz

5th Order 3f 1-2f

23f

2-2f

198 MHZ 103 MHz

3f1+2f2 3f2+2f1 502 MHz 503 MHz

7th Order 4f 1-3f

24f

2-3f

197 MHz 104 MHz

4f1+3f

24f

2+3f

1

9th Order 5f 1-4f2 5f2-4f1 96 MHz 105 MHz

5f1+4f

24f

2+3f

1

e.t.c.

This is why PIM IMD is so

critical!


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Intermodulation

PIM is a result of signal mixing at nonlinearities

In theory IM3 PIM non-linearity increases at a ratio of 3:1 (PIM tosignal)

1 dB increase in carrier power correlates to a theoretical

increase of 3 dB in PIM signal power.

In practice, the actual effect is closer to 2,3-2,5 dB as the thermal noise

constant -174 dBm/ Hz becomes an error contributor.

f1: 3 2 1 0 1 2 3

f2: 4 3 2 1 0 1 2

IM-Order: 7 5 3 1 1 3 5

3rd Order5th Order7th Order 3rd Order 5th Order 7th Order

f2f122.5

MHz

f1 f2

22.5

MHz

22.5

MHz

22.5

MHz

22.5

MHz

22.5

MHz

22.5

MHz

869

MHz

(Main)

891.5

MHz

(Main)846.5MHz

(PIM)824

MHz

(PIM)801.5

MHz

(PIM)

914MHz

(PIM)936.5

MHz

(PIM)959

MHz

(PIM)


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Intermodulation

PIM multiplies bandwidth

If bandwidth of f1 and f2 is 1 MHz then

BWIM3 = 3 MHz

BWIM5 = 5 MHz

BWIM7 = 7 MHz

PIM are clogging up complete RF bands

f1

f2

fIM7

fIM5

fIM3


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Intermodulation

PIM are clogging up complete RF bands

f1 f2

IM 3IM 5IM 7IM 9 IM 3 IM 5 IM 7 IM 9

200 kHz200 kHz

600 kHz

1 MHz

1.4 MHz

1.8 MHz

600 kHz

1 MHz

1.4 MHz

1.8 MHz

PIM bandwidth increases as carrier bandwidth increases

PIM bandwidth increase with PIM order

IM3 bandwidth = 3

200 kHz = 600 kHzIM5 bandwidth = 5 200 kHz = 1000 kHz = 1 MHz

IM3 bandwidth = 7 200 kHz = 1400 kHz = 1.4 MHz

IM3 bandwidth = 9 200 kHz = 1800 kHz = 1.8 MHz


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PIM Root Causes


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Current increases linearly with

applied voltage

High pressure, metal-to-metal

contacts

Welded or soldered

connections

Current

Voltage

Current

Voltage

Current does not increase

linearly with voltage.

Low pressure, metal-to-metal

contacts

Oxide layers on metal surfacesArcing across small air gaps or

cracks

Linear junctions

Non-Linear junctions

What is a non-linear junction?

PIM root causes


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PIM root causes

Contact Non-Linearities caused by

The contact surface between two conductors are on a micro

scale level concave-convex, for instance only some small

bulges connect to each other. This causes non-uniform surface

currents whereby the contact resistance changes

The conductor surface covers a thin oxidized layer whichcauses the diode effect. When surface voltage reaches a

certain level, the tunnel effect is activated

The non-uniformity rust distribution on surfaces is causing a

non-uniform surface current density

Soldering contamination and oxide on connection surface etc.

PIM Causes - Contect Non-Linearities


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Loose metal-to-metal contacts

Poorly terminated RF connectors

Metal flakes inside connectors

Loose RF connectors

Metal flashing on rooftops

Loose rivets, screws, etc.Rusty / corroded surfaces

Non-linear materials

Nickel / Steel

Ferrite

What is a non-linear at cell sites?

PIM root causes


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PIM root causes

Loose and / or inconsistent

metal to metal contactsNot enough contact pressure.

Cracked solder joints

Cold solder joints

Scratches or dents at

mating interfacesBurrs

Metal flakes, chips, dust

Improperly formed or sized

parts

Misaligned parts

Rough mating surfaces (saw

cut)

Loose metal to metal contactsLoose or rusty bolts

Ferromagnetic materials

(steel, nickel, etc.)

ContaminationTrapped between mating

surfaces

Trapped between plating

layers

Solder splatters

Dirt or debrisSurface Oxides

Insufficient thickness of plated

metal causing RF heating

Too much or too little torque at

connections

Root Causes of PIM in a real RF environment


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Why is PIM nowadays a problem?


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Simple antennas

Single Polarization

Single Band

Fixed Electrical Tilt

Single bands per feeder

Tx and Rx on separate feeders

Tx/Rx isolation >50-60 dB!

Why is PIM now a problem?

RX 1

TX

RX 2

PIM

-60 dB -60 dB

In the good old days


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Why is PIM a problem today?

More complex antennasDual Polarization

Dual Band

Remote Electrical Tilt (RET)

More RF connections

Multiple bands per feeder

Tx and Rx combined on each feeder

PIM 60 dB ( 1 million times) worse!

PIM

Tx/Rx

900/1800Tx/Rx

900/1800

Today

PIM is not related to Return Loss,

VSWR or insertion loss!!!

It cannot be detected by Line Sweeps


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What is the goal of PIM problem fixing


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Why do we measure IM3?

A A

f1 f2

IM 3

IM3 is the highest magnitude / most accurate to measure

IM3 characterizes the linearity of the system

Reducing IM3 reduces all PIM products

IM 5IM 7IM 9IM 11

IM 3

IM 5 IM 7

BTS Uplink (Rx) BTS Downlink (Tx)

Decrease IM3


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How is PIM measured


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How is PIM measured?

PIM is measuredacc. to IEC 62037-1 Ed. 1 25.05.2012

Passive RF and microwave devices,

intermodulation level measurement -

Part 1: General requirements and

measuring methods

acc. to IEC 62037-2 Ed. 1 07.11.2012Passive RF and microwave devices,

intermodulation level measurement -

Part 2: Measurement of passive

intermodulation in coaxial cable

assemblies

Standard specifies the use of two 20

watt carriers ( 2 x +43 dBm)

Standard and norms

Typ. min. antenna IM3 PIM Spec. < -150

dBc = < -107 dBm


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How is PIM expressed in measurement results

PIM level is often expressed in dBc, therefore carrier power c must be

provided

0 dBm

IM 3

f1 f2

IM 3-143 dBc

Carrier Power

dBc dBm

0 dBcf1 f2

-100 dBm

+43 dBm


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PIM level relative to measurement power (heuristic approach)

IEC 62037 defines PIM measurement for passive components

(outdoor use)

In-Building components are often not specified for such high power

levels.

They may be damaged when measured with >20 W.

Each dB reduction in carrier power reduces PIM measurementresults approximately by 2.5 dB.

Example:

A spec of -140 dBc measured with 2 x 43 dBm

is equivalent

to -107.5 dBc at 2 x 30 dBm measurements.


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PIM level relative to measurement power (heuristic approach)


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PIM impact on other services


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PIM impacts several services

PIM order versus RF band

Potential high risk to interfere with other

services


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PIM impacts UL-bands of other services

A real example GSM 900 and DCS 1800 networks

By changing TX frequencies you can avoid interference on used RXchannels

Hard to get realized in densely congested spectrum

Example

f1 = 930 MHz, 200 kHz GSM TX

f2 = 958 MHz, 200 kHz GSM TX

fIM3 = 902 MHz (within RX-band)


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PIM impacts UL-bands of other servicesWhy is PIM crucial for GSM service

GSM system is a noise limited systemwhich link budget is based on Eb/N0 in RXEb = Bit Energy, it represents the amount

of energy per bit.

N0 = Noise Spectral Density, unit is

Watts/Hz (or mWatts/Hz)

Eb/N0 = Bit Energy on the Spectral Noise

Density, unit dB

Assuming RX Noise Figure = 5 dB,

RX Sensitivity = -112 dBm in order to

achieve an Eb/N0 = 6-8 dB

(full rate speech coder)

Any PIM Noise generated has to be

significantly lower than -110 dBm in

order not to degrade receiver sensitivity

Required PIM Noise


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Eb/E0 dependency on process gain

After despreading, the baseband (own) signal needs to be typically afew dB above the interference and noise power.

This required signal power density above the noise power density

after despreading is designated as Eb/No.

This quantity is of capital importance because the quality targets are

always expressed as a function of Eb/No as can be seen in the

analysis presented in where the Bit Error Rate probability is derivedin terms of this figure.


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The principle of process gain

As a rule of thumb you can count of the following figures:

Node B: -121 dBm

Mobile: -117 dBm

For example Ericsson receiver sensitivities:

NodeB CS 12,2 -124 dBm

PS-64 -119 dBm

PS-128 -115 dBm

PS-384 -115 dBm

UE CS 12,2 -119 dBm

PS-64 -112 dBm

PS-128 -110 dBm

PS-384 -105 dBm

HSPDA -95 dBm

http://de.slideshare.net/syedus

ama7/umts-interview-qa

BER of 10-3

Required PIM Noise


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Why is PIM crucial for LTE service

LTE system link budget is based on Resource Block (RB)

One RB = 180 kHz

(12 Sub Carriers x 15 kHz each)

Thermal Noise of one RB = -121 dBm

Assuming eNode B receiver Noise Figure = 2 dB,RX Sensitivity = -119 dBm

Any PIM Noise generated has to be significantly lower than -119

dBm in order not to degrade receiver sensitivity

Required PIM Noise


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How does PIM look like under real field

conditions


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Broadband interference Narrow band spikes

What does PIM look like at the site?

What does PIM look like to the operator?


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High average

noise level

Lower average

noise level

QUIET

BUSY

QUIET

BUSY

PIM Repair

Number of lost or dropped calls or enhanced data speed is

converted immediately to money

A good way of churn management

PIM service is a good way of churn management


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Typical cell- and service layout in Stuttgart area

GSM 900

GSM 1800

UMTS 2100

10564

10588

10612

LTE 800

LTE 2600


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A real example PIM within GSM 900 band

PIM


Trouble-free MSn

After switching on the

TRX, you can see an

increased noise increase


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Bad real world field examples


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Poor cable

preparation Dirt /

trash

PIM Field Examples

Field Examples


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PIM Field Examples

Field Examples


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PIM Field ExamplesField Examples

Plenum cable is hollow. Metal particles can fall inside and create PIM.

Hack saws and files MUST NOT be used! PVC pipe cutter provides aclean cut.

Clean cable ends during with isopropyl alcohol during cable prep

Cover unterminated cable ends with plastic caps or electrical tape

Bad flares, ragged cuts, plating damage can result in poor PIM

iBwavesin-buildingtalkswebinarseries07-2013


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PIM Field Examples

Defect main feeder connector

Poor connecter preparation found as PIM

source

Field Examples - Defect Connector

Before connector

replacement

After connector replacement


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PIM Field Examples

Field Example - Defect Connector and its immediate influence

after repair


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Self made PIM sources


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Self-made PIM sources

If you need a PIM source, then

Nut, Bolt & Washer:

On string in front of antenna

Moving in the wind

> 60 dB variation

Steel wool:

Resting on box in front

of antenna

Rocking slightly in the wind

> 9 dB variation


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PIM indicators in cellular networks


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PIM in a Cellular Network

Intermodulation products generated byTX signals can interfere in the RX band.

The common result is that these IMs

can over-power receive channels.

Calls are dropped or

Channels are believed to be occupied

and being used by the BTSLoss of Air Time and thus ARPU

Cell Coverage shrinks

Reduced battery life time

Data Transmission rate drops

RX control loop shows no problem

Antenna sweep detects no issue

RX Noise Level is high

Indicators


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PIM Summary

Macro BTS PIM is of particular concern when

PIM products fall in the RX band

Two or more transmitter channels

share a common antenna

TX signal levels are high

RX sensitivity is high

TX and RX are diplexed

Summary of the phenomenon


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Example: PIM difference between hand-tightend and torque specified

900 MHz band signals with 25 MHz tone separation and each 10 W

carrier power

hand-tightened connector IM3 = -115,3 dB

25 Nm torque-tightened connector IM3 = -173.1 dB

PIM performance of DIN 7/16 connectors

The PIM level of a connector depends on

material, power and torque

DIN 7/16 coax cable connectors

typically PIM values of -140 to -168 dBc

recommended torque (IEC) 35 Nm, in practice often 25 -30 Nm


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Loose connector


PIM of a connector cable assembly

Fastened connector


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PIM Sources within RF interconnections


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PIM sources within the RF interconnection

Co-Siting GSM 900 / GSM 1800 / UMTS

Copyright@Kathrein Corporation


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Co-Siting 3 Op GSM 900 / GSM 1800 and 4 Op UMTS

Copyright@Kathrein Corporation


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PIM sources within

Distributed Antenna Systems (DAS)


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PIM sources within the DAS RF

interconnectionDistributed Antenna Systems (DAS) easy on the first glance


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Distributed Antenna Systems (DAS) not easy on the first glance


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PIM sources within the DAS RF

interconnectionDistributed Antenna Systems in reality sometimes a real challenge


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PIM in DAS

Indoor Antenna Radiation Pattern

700 MHz

1900 MHz

Typical indoor antennas are electrically

small:

700 MHz: = 16 , Antenna < wavelength

1900 MHz: = 6, Antenna > 1 wavelength

Higher side & back radiation at lower

frequency

Sharper radiation pattern at high frequency

Will PIM accepted antenna produce PIM

in indoor environments?

How to reduce back radiation?

Will there be an improvement on installedPIM?


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PIM in DAS

There is another problem that has not been seen in the past

Indoor environments present a PIM

challenge.

PIM producing metal objects abound!

Light fixtures

Ductwork

Ceiling tile frames

Structural steel members

Rebar (in concrete)

PIM survey test to evaluate antenna location

Use antenna that will be installed

Use portable, low PIM mount

Move antenna to find optimum spot

Ongoing PIM survey investigations:Optimum test power to use?

Which frequency bands to use?


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PIM in DAS

PIM created by elevated ceilingsAmazingly high magnitude PIM sources can be found indoors

-80 dBm with 1 W test tones (2 x 30 dBm)

Equivalent to -41 dBm (-84 dBc) with 20 W test tones (2 x 43

dBm)


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PIM in DAS

1900 MHz

Small changes in antenna location can have large impact on PIMRF absorber behind antenna has proven beeing very effective to

reduce PIM

With Absorber, PIM reduced by 40 dB !!!


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Yes, it does partially

Selective antennas

Tower Mounted Amplifiers (TMA)

Combiner, Duplexer, Filter

Lightning surge protectorsLine Sweep test to verify

Use correct PIM test set

By-pass frequency limiting devices


Does it matter at what frequency I test at?


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Yes, it does partially in case of

Selective antennas

Tower Mounted Amplifiers (TMA)

Combiner, Duplexer, Filter

Lightning surge protectors

By-pass frequency limiting components


Does it matter at what frequency I test at?

Yes, it does partially in case of

Line Sweep test to verifyUse correct PIM test set

No, it doesnt in case of

cable and connector measurements


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Does the variation really matter?

Assuming 15 dB reduction in PIM per order (conservative)

Yes, if IM3 or IM5 falls in your RX band

Variation is significant

Measure using same band producing the IM3 or IM5 interference

No IF only higher order products fall in your RX band (IM7, IM9, etc.)

Variation is literally in the noise

Measure using any band that passes through the system


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PIM Measurements


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PIM versus Time


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PIM Measurements

PIM versus time is not static there is a dynamic behavior

PIM magnitude vs. time

Tapping on DUT reveals

real behavior

Excellent visual indication ofPIM stability

Peak PIM held for Pass/Fail

Tapping on RFconnections

Limit Line

Static Test

Tests the base PIM performance

of Cable and Connectors

Dynamic Test

Detect lose contacts in

connectors

Detects contamination in the

connection


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Distance-To-PIM Measurements


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PIM Measurements

DTP - Measure PIM level and location

Shows PIM along a cable

and in an antenna, readout meter

DTP can also measure PIM beyond

an antenna (such as a nearby rusty

cabinet)

Pinpoints bad spots like DTFSetup is very similar to DTF

Unlike PIM, DTP must be calibrated


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PIM Measurements

Measure PIM level and location in a DAS

PIM sources seen at:

0 m

45 m

86.6 m

PIM at test point

reduced by tightening

7/8 connector back nut


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PIM of Radiating Cables


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PIM of Leaky Cables

Radiating cable is sensitive to PIM sources close to the cable.

It doesnt help the fact cables are going to be installed in tunnels

and subway systems near many other metal objects

In this case Distance-to-PIM (DTP) technology

DTP can accurately locate PIM sources along a radiating cable


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PIM Measurements

Measure PIM level and location in Leaky Cable


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PIM Measurements

Finding of hidden and unknown PIM sources

Using Distance-to-Fault to Verify Antenna Location

Using Marker and Delta Marker to Identify Distance-to-PIM beyond

the Antenna


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DTP Measurements

Finding PIM sources beyond the antenna

No need to do this time-consuming and thus expensive job if you useAnritsu Distance-to-PIM (DTP)

Once you have verified the antenna position, use a Delta Marker to

Identify Distance-to-PIM beyond the Antenna

Antenna position? How?


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PIM Measurements

Finding PIM sources beyond the antenna

Concealment site

Antennas hidden inside roof

Possible PIM in front of the

antenna

HiddenAntennas


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PIM Measurements

DTF from VNA, BTS Master

DTP from PIM Master

Be sure to:

Set same start / stop distances

Set same propagation velocity

Calibrate both units at end of

test lead

Set DTF start / stop frequencies:

High bands: 698-896 or 791-960

Low bands: 1710-2170

Low PIM

Termination

PIM

Source

PIM

Source

DTF from VNA, BTS Master

DTP from PIM Master

Be sure to:

Set same start / stop distances

Set same propagation velocity

Calibrate both units

Set DTF start / stopfrequencies:

High bands: 698-896 or 791-960

Low bands: 1710-2170

If possible, sweep as broad as

possible

DTF vs. DTP Overlay with Line Sweep Tools (LST)


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PIM Measurements

DTF vs. DTP Overlay with LST

overlay previous DTF with actual DTP measurement and reveal veryprecise any kind of potential PIM source


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PIM Measurements


overlay previous DTF with actual DTP measurement and reveal veryprecise any kind of potential PIM source (1710 2170 MHz)


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PIM Measurements


overlay previous DTF with actual DTP measurement and reveal veryprecise any kind of potential PIM source


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PIM Measurements

DTP in different RF bands

the more sweep bandwidth the higher the resolution


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PIM Measurements


Resolution = ability to resolve closelyspaced PIM sources

Resolution = (150 * vp) / Sweep

Bandwidth


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PIM Measurements


Too many variables impactaccuracy

Propagation velocity errors

Signal magnitude

Resolution confusion

Electrically long devices (TMA, filters)

Big PIM sources can mask smaller

PIM sources

Remove largest PIM source & repeat

3,5 m

VF = .80

VF = .88


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PIM Measurements

DTP with enhanced resolution

2 x improvement in resolution!

Predictions clearly marked by

red bars on life trace

Location for each prediction

automatically displayed

Speeds DTP trace interpretation

Standard resolution

reports

one PIM source at 16.7 m

Enhanced resolution reports

two PIM sources, 15.7 m and

17.4 m

0m18 m16 m

load

2m16m

2 x PIM sources


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DTP with enhanced resolution

PIM sources 3 m separation


MW82119A-0700

MW82119A-0700

MW82119A-0900


MW82119A-0900



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Swept PIM Measurements

PIM M


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PIM Measurements

PIM levels for individual components combine to give a system PIMlevel.

Combination is similar to the case of system VSWR, except that

feeder and jumper losses provide more padding for far end

components because of the non-linear nature of PIM generation

(typically 2.5 dB variation per 1 dB of carrier variation for 3rdorder).

For example, a 2 dB feeder loss will improve the apparent antennareturn loss as seen on the ground by ~4 dB, but will improve the

apparent PIM by about 7 dB.

PIM contributions from the various components will usually

combine in random phase for a typical system level, which can be

calculated.

But there can be favorable or unfavorable phase combinations togive variations up to a worst case value.

System PIM Level a need for swept PIM measurements

PIM M t


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PIM Measurements

Swept PIM measurements

f1 fixed, f2 swept

f2 fixed, f1 swept

PIM magnitude vs. frequency

shows worst case PIM level

in this example ~13 dB

variation due to phasing!

Multiple PIM signals on combining inand out of phase

13 dB


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Guidelines and Recommondations

G id li & R d ti


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Guidelines & Recommondations

Guideline for PIM testing at the component and system level

Typical PASS / FAIL criteria

Recommendations based on Florida Network US

Test CaseAcceptable Range

@ 2 x 20 W (43 dBm)

Required RF System Maintenance

(coaxial, Antenna, etc,..)

RX Noise Impact

(dBm]

New site installation -140 > PIM > -159 dBcNothing

minimal impact-97 > N > -116 dBm

Existing (aged) site -123 > PIM > -139 dBcOptional

Capacity & Coverage

-80 > N > -96 dBm

Site shows poor performance -100 > PIM > -122 dBcMaintenance Request

Service is affected-57 > N > -79 dBm


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Is there a preferred test process?


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Line Sweep Test (RL, DTF) versus DTP

PIM Measurements


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PIM Measurements

What can you detect with a Sweeper and / or PIM Tester

RF System Problem Detection PIM RL RL (DTF/TD)

Open Circuit Maybe Yes Yes

Short Circuit Maybe Yes Yes

Deformed Coax Cable Probably Yes Yes

Loose connection Yes Probably Yes

Water ingress Probably Probably Yes

Corrosion Yes Probably Probably

Poor material / components Yes Probably Yes

Contaminations (fil ings, wi re edge, plating flecks) Yes No No

Poorly fitting coaxial cable and connector surface Yes No No

Spark marks in surface (from hot disconnects) Yes No No

Dielectric material between coax-cable & connector surface Yes No No

Split in flare due to over-tightening Yes No No

Cracked Solder Joint Yes No No

Internal antenna faults, loose screws, cracked joints Yes No Probably

Small cracks in coaxial cable Yes No No

Loose braid in jumper cable Yes No No

Cell ageing Yes No No


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PIM Master product concept

Anritsu PIM MasterTM


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Anritsu The Solution BoxAnritsu PIM MasterTM

The fastest way to pinpoint the source of PIM

Parameter Specification

Small size: 350 x 314 x 152 mm

Light weight: 9 kg to 12 kg

Batteryoperation: >3.0 hours

Wide power range: 25 dBm to 46 dBm

(0.3 W to 39.8 W)

Residual PIM: -117 dBm @2x 43dBm

-125 dBm typical

Distance-to-PIM: YES

PIM vs. Time: YES

Swept PIM: YES

Noise floor: YES

Remote Control: YES

GPS option: YES



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Anritsu The Solution BoxAnritsu PIM MasterTM

Available frequency models

Frequency Model Number F1 F2 IM

700MHz (L/U) MW82119A-0700 734.0 734.5 MHz 745.0 766.0 MHz698.0 716 MHz

779.5 804 MHz

800 MHz MW82119A-0800 791.0 795.0 MHz 811.5 821.0 MHz 832 862 MHz



1800 MHz MW82119A-0180 18050. 1837.5 MHz 1857.5 1880.0 MHz 1710 1785 MHz


1900/2100 MHz MW82119A-0192 1930.0 1935.0 MHz 2110.0 2155.0 MHz 1710 1755 MHz

2100 MHz MW82119A-0210 2110.0 2112.5 MHz 2130.0 2170.0 MHz1920 1980 MHz

2050 2090 MHz




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2 to 3 hour Battery LifeReplaceable

Same as other Anritsu HHs

Production tested for reliability

50 hour burn-in

2 hour thermally cycled

Designed tested for reliability

HALT Test

Vibration Test

Shock Test

Drop Test

Designed and tested like all Anritsu Handhelds



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Optional Transit case


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Optional Transit case

Space for PIM Master inside

soft case

Storage boxes

Contents shown for

example only

Retractable handle

Foam padding to protect

contents

4x snap latch

Impact resistant, hard

case

Lifting handles

Weather seal760-259-R


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Optional Backpack Accessory Kit


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Optional Backpack Accessory Kit

2000-1746-R

ContentAnritsu Backpack (P/N 67135),

PIM Test Cable (P/N 2000-1626-R),

Low PIM Termination (P/N 2000-1724-R),

PIM Standard 1800 MHz (P/N 1091-390-R),

2 x Low PIM Adapters (P/N 1091-425-R),

2 x Low PIM Adapters (P/N 1091-426-R),

Low PIM Adapter (P/N 1091-427-R),

Cresent Wrench (P/N 01-510),

Torque Wrench (P/N 01-513-R),

Isopropyl Wipes (P/N 971-9-R),

Tapered double tip swabs (P/N 971-10-R)


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PIM Master Equipment Verification Process


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Level compatibility between PIM Standard 900 MHz and 1800 MHz



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Level compatibility between PIM Standard 900 MHz and 1800 MHz

PIM Master What do you need?


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Batteries / charger

One battery comes with PIM

MasterTwo spares + external charger

enables continuous use

Transit caseWeather protection

Shock protection in

vehicle

Shipping container

Accessory kit

Anritsu kit is a PREMIUM kitCustomer may already have

this!

Okay to use existing kit

Recommended configuration

PIM Master What do you need?

PIM Master What do you get for free?


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Anritsu The Solution BoxLine Sweep Tools Documentation (LST)

Line Sweep Tools enable to

Collect traces from the

instruments

Verify that the traces are

correct using markers and

limit lines

Report results in industry

accepted PDF and/or DAT file

format

Line Sweep Tools features

Marker and limit line presets

Quick file name, trace name,

and sub-title renaming

Automated report generation

PIM analysis and reportingcapability

LMR Master and VNA Master

Field Mode compatibility




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Line Sweep Tools Documentation (LST)

Reporting after measurementhas been done in order to

secure service payments

Report Generation with

Line Sweep Tools

PIM Level versus time

Distance-To-PIM

Return Loss

Distance-to-Fault

Insertion Loss



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General Function principle of PIM

measurements

General Function principle of PIM measurements


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General Function principle of PIM measurements

Prior conventional way to measure PIM during the good old days


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General Function principle of MW821xA



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F1 & F2 can be any frequency

power produced goes into load

Fans required to remove heat dissipated in load

IM RX

Duplexer

Load

Receiver

F1 (40W)

F2 (40W)

(2x 20W)

(2x 20W)

TX

Hybrid Combiner

How does MW821xA PIM test equipment work?



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A hybrid combiner design utilizesa 3 dB quadrature hybrid coupler

to split the two input signals F1and F2 equally between the two

output ports of the coupler.

Advantages of this approach

include small size, low cost and

broad operating bandwidth.The disadvantage of a hybrid

combiner is power consumption.

Since the hybrid coupler splits

one half of each signal between

the two output ports of the

device, it requires two times the

input power to achieve a given

output level.


Hybrid Combiner


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General Function principle of MW82119A

General Function principle of MW82119A


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p p

IM RX

Duplexer

Receiver

F1

F2 TX

Inject two test tones into a system

Tightly controlled frequencies

High power (2 x 20 W typical)

Measure & report the magnitude of the IM produced

Tx combiner

Load

DUT

Must be

low PIM !

PIM


How does MW82119A PIM test equipment

ork?


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A filter combiner design utilizes

cavity band-pass filters toefficiently combine signals from

two neighboring frequency bands

onto a common output port.

Advantage very low insertion

loss

Disadvantage - is size, weight,cost and frequency bandwidth.

Filter combiners do not allow all

frequencies in the downlink band

to be selected for PIM testing.

Rather, a space or guard band is

required to achieve isolation

between neighboring frequencybands

work?Filter Combiner

How does MW82119A PIM test equipment work?


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The MW82119A is designed tomaximize the range of IM3

frequencies that can be generated in

the uplink band using F1 and F2 test

signals from the downlink band of

that system.

Placing F1and F

2at the farthest

allowable spacing will identify the far

limit of the IM3 range.

Lowest possible IM3 frequency

q p

TX test tone range setting

How does MW82119A PIM test equipment

work?


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The MW82119A is designed tomaximize the range of IM3

frequencies that can be generated

in the uplink band using F1 and F2test signals from the downlink band

of that system.

Placing F1 and F2 at the farthest

allowable spacing will identify the

far limit of the IM3 range.

The near limit to the IM3 range

coincides with the near limit of the

uplink band itself.

Highest possible IM3 frequency

work?TX test tone range setting


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Summary

Passive Intermodulation Measurements


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PIM = reduces site performance

PIM sources can be eliminated / minimized through:

Careful construction techniques

Use of low PIM components.

Careful site design.

PIM testing should be dynamic (not static)

PIM testing AND Line Sweep testing (VSWR) are

needed to

verify system performance.

EDUCATE and TRAIN installation personal on PIM

and PIM Prevention

Summary Statement

Passive Intermodulation Measurements


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1 dB improvement in receiver sensitivity canmean as much as 11% fewer radio base stations

All the time a question of CAPEX and OPEX

Source: Harri Holma and Antii Toskala, WCDMA & UTMS Nokia

Finland 2004. publisher John Wiley and Son USA


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Practical PIM measurements

Practical demonstration


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Lab demonstration I

To be measured

Uplink spectrum

RL / DTF

PIM level versus time

DTP

Swept PIM

(eventually)

DTF versus DTPoverlay10 m

6 m

6 m

Further on

Is there a differencebetween hand tight

and torch wrench?

Where is my antenna?

Do I have PIM in front

of the antenna?

RG214 cable



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Lab demonstration II

To be

measuredSame as

before

(50 LOAD)

10 m

6 m

6 m

Further on

What is the impactof the TMD?

TMD 900/1800

K 80010667

VPol Panel 872960 907.5dBi

Practical measurement demonstration


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M1 PIM vs Time Complete antenne lineM2 PIM vs Time Antenna removed and feeder line with PIM Load

terminated

M3 DTP of M2

M4 DTP enhanced of M2

M5 PIM Source at 16 m removed

M6 TMD exchanged against a new one, result: less PIM

next removed, because TMD input port is creating PIM

M7 Antenna reconnected

M8 Antenna with steel wool on radome

M9 Antenna swapped against another type (Kathrein)

M10 Antenna with close by located clotheshorse with attached steelwool



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Residual PIM level measurement



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Uplink noise floor measurement


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Distance-to-PIM parameter settings



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PIM vs Time of entire feeder line including antenna



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Antenna removed and feeder line terminated with PIM Load



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DTP



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Enhanced DTP



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PIM source at 16 m removed



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TMD first swapped and then removed



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Antenna reconnected



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Antenna with steel wool on radome



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Antenna swapped against a Kathrein type



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Antenna swapped against a Kathrein type



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Antenna with close by clotheshorse and attached steel wool

A l l h h d h d l l



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Antenna close to clotheshorse and attached steel wool

Documents

Pim x Tim by Anritsu