manjiri pande and team rfss, iadd barc

325 MHz solid state RF amplifier development at

BARC under IIFC

Manjiri Pande and Team

RFSS, IADD

BARC

Outline

1. RF devices

2. Solid State RF Amplifier topology

3. Solid State RF Amplifier (@ 325 MHz) development under IIFC3. Solid State RF Amplifier (@ 325 MHz) development under IIFC

4. Schedule

IIFC meeting- 325 MHz RF- manjiri - IADD-BARC

Available RF Technologies

February 27, 2015 IIFC meeting- 325 MHz RF- manjiri - IADD-BARC

4February 27, 2015 IIFC meeting- 325 MHz RF- manjiri - IADD-BARC

Solid State RF AmplifiersThe advantages of solid state amplifier

� No High Voltage and Vacuum requirement

� No filament, no warm up time and simple start up procedures

� High Reliability

� Modular Design

� Graceful Degradation

� Easy and Fast Maintenance

� Better RF signal (Harmonics, Phase Noise etc.)

� Overall moderate Cost� Overall moderate Cost

Expected decrease in Price/Watt and Size/Watt due to world-wide R&D efforts

Solid State RF Power Amplifier Development at 325 MHzSolid State RF Power Amplifier Development at 325 MHz

� MOSFET based RF power modules

� Input RF power is divided into ‘n’ parts (1:n)

� ‘n’ no. of individual RF modules amplifies the power

� The output power from these ‘n’ modules is combined (n:1) to get higher

power

� The high efficiency RF amplifier modules of 1 kW have been developed

� Technology of Power Dividers Combiners (PDC) at various power levels


Solid State Amplifier: The basic Building blocks

Output RF power of individual solid state device is medium, maximum up to 1200

Watts. Hence higher power level of the order of few kW level can be obtained by

summing output of multiple power modules using power combiners. Different

constituent blocks which need to be developed separately, are as shown

Output RF power of individual solid state device is medium, maximum up to 1200

Watts. Hence higher power level of the order of few kW level can be obtained by

summing output of multiple power modules using power combiners. Different

constituent blocks which need to be developed separately, are as shown

6February 27, 2015 IIFC meeting- 325 MHz RF- manjiri - IADD-BARC

Architecture of SSRFPA

we

r sp

litt

er

we

r co

mb

ine

r

PA

PA n

Directional

coupler

n

ControlSignal

RF

Load

The variation in phase and amplitude

of amplifier modules demands for

proper summation at combiners that

leads to good combining efficiency.

Due to divide and

combine strategy, the

design of each part is

equally importantn

RF

signalDriver

Po

we

r sp

lit

po

we

r co

mb

PA

1P

A

coupler

1

Compact DC supplies Interlock and Protection Water cooling

RF

Switch

Load

1


• Deliverables under the collaboration and under Addendum V

� 1

� 1 kW, 325 MHz, solid state power amplifier (SSPA) – Completed

Indian Institute and Fermi Lab Collaboration (IIFCIndian Institute and Fermi Lab Collaboration (IIFC))

� 1 kW, 325 MHz, solid state power amplifier (SSPA) – Completed

� 3 kW, 325 MHz, solid state power amplifier (SSPA) – Completed and delivered

� 7 kW, 325 MHz, solid state power amplifier (SSPA) – Bench tested W, 325 MHz,

solid state power amplifier (SSPA) – Bench tested.

• In the next phase, 30 numbers of 10 kW, 325 MHz, solid state power amplifier

(SSPA) need to be developed under IIFC

Status: Design completed

February 27, 20158


Our aim was and is, to design and develop

1) the high efficiency (RF) power modules

2) Power dividers / combiners (PDC) with good matching

3) Directional couplers for RF power measurement

andand

1) Use compact DC supplies

2) Use reliable interlock and protection for safe operation of RFPA

3) Achieve excellent efficiency and power gain of the amplifier

Started with technology development of the most important basic building blocks of

R &D done for RF power modules and power dividers/ combinersR &D done for RF power modules and power dividers/ combiners

9

Started with technology development of the most important basic building blocks of

SSPA, i.e.

1) High efficiency RF amplifier power modules (1 kW) and

2) Power combiner /divider technology at various power levels

A 325 MHz, 1 kW - Amplifier module was designed. Substantial investigation was

done using different laminates based on their properties like dielectric strength,

thermal conductivity etc. During development period, modules were developed

using three types of printed circuit boards (pcb) material (laminates) as,

a) FR4

b) Ceramic filled PTFE

c) Glass microfiber reinforced PTFE


Main SpecificationsFermi Lab

specs

FR4

(BARC)

Glass microfiber

reinforced PTFE

(BARC)

Ceramic filled

PTFE

(BARC)

Center

frequency (MHz)325 325 325 325

Power output (W)

(single module)1000

1000

(short term)

800 (long term)

1000 (short term)>1000

Power Gain (dB)

(Overall)60

>60

( individual

module19.3)

> 60

( individual module:

21.8)

> 60

( individual

module: 22.8)

Comparison of Specifications

module19.3) 21.8) module: 22.8)

Efficiency(AC/RF) (%)

(module)> 60 < 60% 62 > 63

Issues if any Thermal issue Thermal issue No issues

Status Discontinued Discontinued Adopted for 1, 3, 7 and

10 kW amplifiers

Thermal/Heat transfer

efficiency-- Poor Good V. Good


R&D and development RF Power Amplifier Modules

Center Frequency : 350, 352 , 325 MHz

Power output (sat.) : 100 W, 300 W, 800 W, 1000W

Power Gain : 8.5-20 dB

The PAPA modulemodule is the main buildingbuilding blockblock. It determines the

system linearity, efficiency and power consumption.

Its design at high power, involves study of issues like RF

transistor selection, device model, device efficiency, operating

modes and device parasitic effect.

Power Gain : 8.5-20 dB

Efficiency : 50 - 68%

Protection : Circulator

CirculatorDevice

O/p Balun

Load

I/p Balun

O/P

I/P

250W Amplifier moduleFebruary 27, 2015


R&D and development RF Power Amplifier Modules

300W Amplifier module at 352 MHz

1kW Amplifier module at 325 MHz 800W Amplifier module on

FR4 laminate


R&D and development of Power Dividers /Combiners

• Combiners designed using pcb and coaxial lines.

• 2, 4, 8-way combiners

• Power levels 100 W, 1 kW, 10 kW.

• Return loss of >20dB at input ports (with phase coherence)

• Return loss of better than 25dB at output port.

• Isolation among input ports better than 25dB.

• Transmission loss < 0.15dB

2-way splitter

2-way combiner

4- way pcb based

Combiner/splitter4- way, 3 kW coaxial

Combiner/splitterFebruary 27, 2015


Power Dividers /Combiners - - continued

8 way, pcb based

Combiner/splitter

10 kW, 2-way, coaxial

Combiner/splitter

5 kW, 8 way, coaxial

Combiner/splitter @

352 MHz


Combiner/splitter

Combiner/splitter


Combiner/splitter @ 325 MHz

February 27, 2015


Directional Coupler: Design and development

Directional coupler 1 kW

at 325 MHzDirectional coupler 500

Watt at 325 MHz

Simulated directional

coupler 3 kW at 325 MHz

Manjiri/IADD/BARC/V- IIFC meet

Watt at 325 MHz

Directional coupler 3 kW

@ 325 MHz with BW of 30

MHz

Parameters Results with low RF signal (dB)

Isolation -72

Coupling - 44.4

Directivity 27.6


All are stand alone RF amplifiers and are designed and developed indigenously

Contribution under IIFC: Solid State RF amplifiers at 325 MHz

• Power: 3 kW

• Overall Gain: > 65 dB

• Efficiency : 65 %

• 2nd Harmonics: - 41.9 dB

• Power: 1 kW

• Overall Gain: > 65dB

• Efficiency : 61 %

• 2nd Harmonics: - 41.5 dB

1 kW Amplifier3 kW Amplifier 7 kW Amplifier

• Power: 7 kW

• Overall Gain: > 90 dB

• Efficiency : 66.3 %

• 2nd Harmonics: -41.9 dB

February 27, 201516


This 3 kW @ 325 MHz work has been published in:

Journal: Nuclear Instruments and Methods in Physics Research

A 735(2014) 283–290

Title: Development of 3kW, 325MHz solid-state RF power amplifier

using four power amplifier modules

Authors: B.V. Ramarao , S Sonal, J. K. Mishra , M. Pande, P. Singh, G Kumar,

J. Mukherji

February 27, 2015IIFC meeting- 325 MHz RF- manjiri - IADD-BARC

7 kW, 325 MHz SSRFPA

PowerMeter

PowerMeter

200 W

Sig. Generator

10 kWLoad

PowerMeter

DC

50V, 30A

each

(8)

Water

cooling

8:1

Combiner

1:8

Divider

200 W1-5/8” line

NRT-Z44NRT-Z44

50 W SSPA

Feb 27,2015IIFC meeting- 325 MHz RF- manjiri - IADD-BARC

7 kW, 325 MHz RF amplifier

Feb 27, 2015

Assembled and tested unit of 7 kW SSRFPA Interlock card under

development


7 kW, 325 MHz SSRFPA

RF Power

Waveform

at 7 kW on

spectrum

analyzer

Display of

Calorimetric

measurement of

RF Power

Sensor data of

Calorimetric

measurement of

RF Power


7 kW, 325 MHz RF Power Amplifier

• The amplifier sub-systems (i.e. amplifier modules, DC power supplies,

combiner etc.) have been assembled in the stand alone amplifier rack

• Testing at 7.5 kW RFPA has been completed

• Evaluation of the amplifier is completed

Results of testing

i. Power rating: 7.5 kW at 325 MHz

ii. Bandwidth: > +/-5 MHz (1 dB)

iii. Power Gain: 21.6 dB

iv. Overall conversion efficiency: 66.3%

v. Compression power (at 1 dB): 7.3 kW

vi. Harmonic contents: < -50 dBc

vii. Radiated emission measured outside unit: 3.1 V/m

Feb 27, 2015

21IIFC- 325 MHz RF- meeting- manjiri - IADD-BARC

Evaluation of SSRFPA

Feb 27, 2015 22

parameters Pin (W) Power (kW) Gain (dB) Efficiency (%) 2nd Harmonics 3nd Harmonics VSWR- in

1 63.4 8.1 21.0 68.3 -47.6 dBc -66 dBc 1.25

2 53.7 7.6 21.5 67.6 -48.7 dBc -66 dBc 1.18

3 38.5 6.4 22.2 64.4 -49.8 dBc -67 dBc 1.06

IIFC- 325 MHz RF- meeting- manjiri - IADD-BARC

Evaluation of SSRFPA

Feb 27, 2015 IIFC- 325 MHz RF- meeting- manjiri - IADD-BARC

This 7 kW @ 325 MHZ work has been published in,

Journal: Nuclear Instruments and Methods in Physics Research A 764 (2014)

247–256

Title: A compact high efficiency 8kW, 325 MHz power amplifier for accelerator

applications

Authors: Jitendra Kumar Mishra , B.V. Ramarao, Manjiri Pande, P. Singh


Feb 27, 2015

10 kW, 325 MHz SSRF power amplifier

• Design of the 10 kW amplifier has been completed based

on the FRS for 7 kW RFPA

• 1 kW amplifier module for this amplifier is same as that

used in 7 kW amplifier.

Main component procurement and fabrication work has• Main component procurement and fabrication work has

started for first prototype unit

• Design may get modified based on detail information to be

received from FNAL

Feb 27, 2015 IIFC- 325 MHz RF--meeting- manjiri - IADD-BARC

Information Required from FNAL for 10 kW RFPA

• The functional requirement specification (FRS) and technical requirement

specification (TRS) document to be received from Fermi lab. Details of vibration and

shock test, overall dimensions, system layout and remote Interfacing etc. need to be

discussed and finalized

• RF Interface, high power RF testing details for SRF cavity and remote control

interface format need to be provided by Fermi lab, detailed discussion with RF and

control team of Fermi lab to be carried out

Feb 27, 201526

• Required physical foot prints and layouts for 10 kW, 325 MHz RF amplifier units

including circulator and transmission line components

• Details of EMI/EMC standards, to be followed and acceptance test criteria/

procedures to be followed

• Specific requirement if any, regarding electronic components and subsystems used

in fabrication of 10 kW RF power systems need to be supplied. Any restrictions of

components and material, to be used in making the RF power systems, need to be

mentioned.IIFC- 325 MHz RF- meeting- manjiri - IADD-BARC

Information Required from FNAL - -

• Details of the water cooling systems inlet/outlet connectors, pressure drop,

tolerable inlet temperature etc needs to be mentioned

• Quality assurance plans

• Standards, certification requirements

• Packaging requirements

Feb 27, 2015

• Packaging requirements


Delivery Schedule of 10 kW SSRFPA

Sr.

No.2015 2016 1/4/2017 1/12/2017 2018 2019 2020 2021 2022

1 BARC -- -- 01 01 -- -- -- -- --

2 BARC-

ECIL

Technology transfer to ECIL and

production of subsequent 10 kW unitsX* X* X* X* X*

ECIL production of subsequent 10 kW units

*Subject to discussion with ECIL

IIFC- 325 MHz RF- meeting- manjiri - IADD-BARCFeb 27, 2015

Conclusion

• Design topology for high efficiency RF power modules is proven

with results

• Design topology for good power splitters / combiners is proven

with results

• RF amplifiers at 1, 3, 7 kW have been developed and tested as

per its design specifications per its design specifications

• Optimization of RF parameters for further improvements is in

progress

• For 10 kW RFPA, design is completed and purchase of main

components for one prototype unit is underway.

• For 10 kW RFPA, design or some additional features may get

added based on the feedback from FNAL

Feb 27, 2015 IIFC- 325 MHz RF- meeting- manjiri - IADD-BARC

RFSS /IADD/BARCTeam

1. Mrs. Manjiri Pande

2. Mr. B.V.R.Rao

3. Mr. J.K.Mishra3. Mr. J.K.Mishra

4. Mrs. S.V.Sharma

5.Mr. S.D.Shrotriya

6.Mr. N.R.Patel

7.Mr. S.Muthu

8. Mr. Hitesh Kadam

IIFC- 325 MHz RF- meeting- manjiri - IADD-BARCFeb 27, 2015

Thank

You !You !

31Feb 27, 2015 IIFC- 325 MHz RF- meeting- manjiri - IADD-BARC

manjiri pande and team rfss, iadd barc

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