ID OSA Optical Spectrum Analyser for Satellite & Space Communication

Why Space Communication Terminals Are Checked on the Ground

An optical terminal for space communication cannot be adjusted once it is in orbit. Its laser, modulator and booster amplifier have to be characterised on the ground, and the results compared from one stage of development and qualification to the next. Centre wavelength, side-mode suppression and the shape of the modulated spectrum all need to stay where the design expects them.

These ground tests often run as long campaigns, with the same parts measured repeatedly as they move from breadboard to engineering model. The spectrum analyser used for this work should give a consistent baseline across the whole campaign, so that a change in the readings reflects the hardware under test rather than the instrument.

The Optical Spectrum Analyser in a Terminal Test Lab

The ID OSA optical spectrum analyser from ID Photonics measures by coherent detection. It mixes the incoming light with an internal tunable laser reference and reconstructs the spectrum from the result, instead of scanning a diffraction grating.

Its solid-state design has no moving optical parts. In space communication labs it is used to check laser sources, characterise booster amplifier outputs and look at the spectra of modulated signals during development and qualification testing on the ground.

Why Power Range and Frequency Accuracy Matter

Terminal hardware produces signals at very different levels, so the analyser has to cover both ends:

• Amplified outputs: the standard port takes −30 to +23 dBm, so booster amplifier outputs can be checked at their working level.
• Weak or tapped signals: the high-sensitivity port takes −60 to +3 dBm, for monitor taps and low-level signals.
• Frequency accuracy: ±1 GHz (±8 pm) shows whether a laser sits on its planned wavelength from one test session to the next.

Built for Space Research Laboratories

The ID OSA is a half-width 19-inch, 1.8 kg instrument that fits on a bench or in a test rack.

Laser characterisation

Centre wavelength, spectral width and side-mode suppression of DFB, DBR and narrow linewidth lasers can be checked with 2.5 pm spectral sampling, and chirp can be studied on directly modulated sources.

C-band and L-band

The C-band covers 1528.5 to 1567.5 nm and the L-band 1569.08 to 1609.73 nm, so one instrument serves terminal designs in either band.

Repeatable power readings

Relative power accuracy is 0.4 dB and absolute power accuracy ±0.7 dB, with optical return loss above 35 dB.

Scripted test campaigns

USB, Ethernet, a browser GUI and SCPI commands for Python, LabVIEW and MATLAB, plus a 3.3 V TTL trigger, let the same measurements be repeated across a campaign. The unit runs from a 100 to 240 V supply at 40 W and operates from 0 to 40 °C.

Building a Complete Terminal Test Bench

The terminal’s optical source can be a Narrow Linewidth Tunable Laser Source, whose spectrum the optical spectrum analyser checks first. When the team modulates it with its own modulators, the Automatic Bias Control System keeps them locked. The PM EDFA boosts the signal in the C-band, and the OSA’s standard port measures its output. On the receive side, the CORX Coherent Optical IQ Receiver measures the constellation and EVM of the same signal.

Who Uses It

• Space research centres and satellite communication programmes
• Optical terminal and free-space optical communication developers
• Laser and optical amplifier makers supplying space projects
• Defence research laboratories working on optical links
• Photonics groups at IITs, universities and research institutes

Supply and Support in India

United Spectrum Instruments (USI), Chennai, supplies the ID OSA optical spectrum analyser in India as the distributor for ID Photonics, together with the narrow linewidth laser, Automatic Bias Control System, PM EDFA and CORX receiver.

Sourcing the bench from one supplier gives space communication teams a single point of contact for band choice, port use, automation, installation and after-sales support, with pre-sales guidance on matching the analyser to the tests in each campaign.

Request a Configuration

Download the brochure from this page, use the Enquire Now button, write to sales@unitedspectrum.in, or call +91 93631 83748 / +91 97899 04948. Please mention:

• The bands you need: C-band, L-band or both
• What you will measure: lasers, amplifiers or modulated signals
• The power levels at the point of measurement
• The length of the test campaign and how results will be logged