Back End Preliminary Design Review, 2002 April 24-25, Granada, Spain AtacamaLargeMillimeterArray DTS FO Hardware Design Bryan Anderson Jodrell Bank Observatory.

Back End Preliminary Design Review, 2002 April 24-25, Granada, Spain

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DTS FO Hardware DTS FO Hardware DesignDesignBryan AndersonBryan AndersonJodrell Bank Jodrell Bank Observatory Observatory

Co-authors: D.C. Brown, M. Bentley & R. McCool

DTS FO Hardware Design04/21/23

Back End Preliminary Design Review, 2002 April 24-25, Granada, Spain

2

ALMA Project

Contents of Talk

• Fibre Interconnects (everywhere)• Optical Receiver (correlator, AOS or OSF)• Optical Transmitter (antenna)• Optical Multiplexer-Monitor Module (antenna)• Optical-Fibre Amplifier Module (AOS)• Optical Demultiplexer-Switch Module (AOS/OSF)• Monitor, Control and Safety

DTS FO Hardware Design04/21/23

Back End Preliminary Design Review, 2002 April 24-25, Granada, Spain

3

ALMA Project

OLA

OLA

Patch

Panel

8 fibres

250wide

8 fibres

64wide

Fibre

Manage

64 fibres

OtherServices

64 wide

1:12demuxswitch

1:12demuxswitch

64:1switch OSA

3 wide 192 wide

To

correlator

quadrants

7 wide

DTS FO Hardware Design04/21/23

Back End Preliminary Design Review, 2002 April 24-25, Granada, Spain

4

ALMA Project

switching

regulator

regulator

regulator

switching

linear

48 V

+3.3 V

-2.0 V

+8 V

+12 V

MTRX192L

one of three

PIC

16F877

compensation

ADC12-bit

DAC12-bit

powermonitor

keep-alive

M&C bus

DTS FO Hardware Design04/21/23

Back End Preliminary Design Review, 2002 April 24-25, Granada, Spain

5

ALMA Project

Optical Receiver

DTS FO Hardware Design04/21/23

Back End Preliminary Design Review, 2002 April 24-25, Granada, Spain

6

ALMA Project PIC

16F877

switching

regulator

regulator

regulator

switching

switching

48 V

+5.0 V

+5.0 V

-5.2 V

TECTH

mod

driver

EAM

MD

LD

current

temp

current

power

Agere E2580

switching

TECdriver

LDdriver

duty cycle

drive

offset

temp

power

TECs

LDs

driversEAM

10 Gbps

light

12-bitADC

12-bitDAC

12-bitDAC

12-bitDAC

12-bitDAC

12-bitDAC

keep-alive

M&C bus

DTS FO Hardware Design04/21/23

Back End Preliminary Design Review, 2002 April 24-25, Granada, Spain

7

ALMA Project

optical

mux

12:1

wide12

overpower

detector

alives

keep

-20 dB

DTS FO Hardware Design04/21/23

Back End Preliminary Design Review, 2002 April 24-25, Granada, Spain

8

ALMA Project

Optical-Fibre Amplifier Module

• Uses an oem EDFA module– 20 dB gain, +17 dBm output power– Size: 100 x 100 x 15 mm– Interface: RS232, 25-pin connector, +5V @ 6 -

8W off 48V bus

• Plug-in with PIC controller, 8 per crate, 64 OFAM in 2 racks

• Keep-alive feedback from 4 sets of receivers

DTS FO Hardware Design04/21/23

Back End Preliminary Design Review, 2002 April 24-25, Granada, Spain

9

ALMA Project

Optical Demux-Switch Module

WDM

demux

optical

4 x 4

switch

optical

4 x 4

switch

optical

4 x 4

switch

quadrants

correlator

To

ganged control

DTS FO Hardware Design04/21/23

Back End Preliminary Design Review, 2002 April 24-25, Granada, Spain

10

ALMA Project

Optical Demux-Switch Module

• Integrate demux-switch functions: hide 12 interconnects

• Make as plug-ins with PIC controller and power supply off 48V bus

• 4 ODSMs per crate • 4 - 6 crates per rack• Requires total of 3 - 4 racks

DTS FO Hardware Design04/21/23

Back End Preliminary Design Review, 2002 April 24-25, Granada, Spain

11

ALMA Project

Monitor and Control

• Slaves: answer only• Report the truth• Remember calibrations and exceptions• Parameters in non-volatile memory• Monitor and control everything: no

potentiometers• Set/trip out philosophy for safety

DTS FO Hardware Design04/21/23

Back End Preliminary Design Review, 2002 April 24-25, Granada, Spain

12

ALMA Project

Safety

• By design– Physical access restricted– Switch on under software control– Switch off via hardware or software

• Soft switching for transmitters?– Hardware keep-alives:

• OMMM to transmitters• Receivers to optical amplifiers (256 twisted

pairs!)