First laser-based data transmission between satellites

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:__~I~ _.___ ~.._ _~__ _~__._~~..__ _._ _‘.-_._._._ -..--~---~~---.-~-~.-__ Technology:

Optoelectronics

First laser-based data transmission between satellites In November, the first data link

earth at an altitude of 832 km).

position

was established

The test was organised and

lower parking orbit at 31 000

between

satel-

lites using a laser beam as sig-

technically

nal carrier.

ESA team at Redu, Belgium and cooperation

and built by Astrium) provides

with the CNES

SPOT 4 operational

an optical data transmission satellite (built

hours. When in line-of-sight (for 420 minutes each orbit), images

team in

taken by SPOT 4 can now be

Toulouse.

ESA’s Artemis

communication

km, circling the Earth every 19

by an

an Astrium team at Fucino in

The SILEX system (designed

link between

supported

but in a tempory

transmitted

The main challenge

in real time at 50

Mb/s via Artemis to the image

in estab-

lishing an optical link between

processing

satellites is to point a very nar-

Image in Toulouse, France.

2001 and operated from a con-

row beam with extreme

The first experimental

trol station in Fucino, Italy by

cy to illuminate

under the leadership

of Italy’s

Alenia Spazio, launched

in July

accura-

the partner

the Alenia Spazioflelespazio

spacecraft

consortium

7000 m/s.The experiment

Altel - see Issue 8,

centre at Spot

transmis-

sion of a SPOT 4 image was

flying at a speed of was

due in early December.

From

Christmas to mid-2002, the ion-

page 46) and the French space

performed

under worst-case

propulsion

agency CNES’ Earth observation

conditions

since Artemis is not

Artemis to its Bnal geostation-

satellite SPOT 4 (orbiting

in its nominal geostationary

the

phase will move

ary orbit at 36,000

km.

Coolerless 980 nm modules Blue Sky Research

Due to integration

(Milpitas,

greatly increases

Coolerless

of the package

turing yields”, pricing

50-120 mW, without

hermetically

of

replacement

by

butterfly

High-output

Electronics

Device Group Electric

&

USA Inc

launched

the ML9XXI8

series

of InGaAsP 10 Gb/s distributed feedback

(DFB) lasers (with a

high extinction

ratio of 11 dB, a

high side-mode suppression

for direct

devices)

us$l,ooo.

40 mW cw DFB laser chirping

low

characteristic

that

(Clinton, NJ, USA) and its parent

enables long-distance,

high-

company The Furukawa

capacity transmission.

Inc

Co Ltd (Japan) are

continuous

(DFB) laser mod-

ule for long-distance

transmis-

sion in DWDM systems currently

40 mW

wave (CW) distrib-

uted feedback

of

should enable

which

resulting in an extremely

a high-output

manufac-

entire EDFA units at under

of standard

14xx and 980 nm pump laser

delivering

US$400

sealed TO-can

supplier Fitel Technologies

Electric

(Sunnyvale, CA, USA) has

level (in a

mount, packaged

cooling

end-Q1/2002.

of Mitsubishi

costs and

at the diode level instead

from 0-70°C) for production

The Electronic

assembly, lowers

EPM980 highly stable 980 nm Laser Pump

pLens technology

production

proprietary

Module (with output powers

Mitsubishi’s 10 Gb/s DFB

“simplifies

of its

CA, USA) is sampling its

-

the highest-power

and one FP, which vary in power from 0.05-l .6mW, are available in three different

The modules are available in a full I~oo-1625nm

ITU-T wave-

length line-up to support large channel counts and the growing reliance on L- and S-bands. * Fitel has also launched

The suite of four DFB modules

a

package designs: MF Pigtail module, RC module, and LC module. The Ml and M2 series of uncooled

1310,151O

and 1550

nm DFB modules are for intermediate- and long-haul use.The

CW DFB commercially

series of low-cost, uncooled

1470-1610

available (rather than the typi-

coaxial Distributed

Course Wavelength

cal lo-20 mW).

(up to 2.5Gb/s) and Fabry

Multiplexing.

(EA) modulator to create a

The laser helps to maintain sig-

Perot (FP) laser modules which

The 13 10 nm FP module for

15 50 nm light source that is

nal strength versus optical loss

enables extremely

intermediate

stable for short- and intermedi-

when combined

consumption

ratio of 40 dB, and a fast response integrate

time of 30 ps).These an electro-absorption

ate-reach data transmissions

REVIEW

Niobate modulator

and wave-

length division multiplexer,

to 50 km.

Ill-Vs

up

with a Lithium

THE ADVANCED

SEMICONDUCTOR

MAGAZINE

VOL15

- NO I- jan/Feb

Feedback

low power

and small mount-

ing size due to the absence thermoelectric

2002

cooler.

of a

nm MX series is for Division

use supports

SONET/SDH and Fiber-in-theloop (FITL) compliant

links for

speeds up to 622 Mb/s.