Satellite tracking antenna at CTTC’s experimental ground segment

01 / A testbed for what comes next

Build. Connect.
Experiment.

From software-defined radio to cloud computing. CASTLE brings communications research closer to real-world experimentation.

Explore the infrastructure Plan an experiment

CTTC · Castelldefels, Barcelona

CTTC / Connected experimental infrastructure

RadioSoftware-defined experimentation

CloudCompute & remote workflows

SatelliteHybrid network research

Open toolsSoftware & research resources

02 / The platform

One testbed.
Many possibilities.

CASTLE — Cloud Architecture for STandards deveLopmEnt — is CTTC’s platform for developing and evaluating communications systems. Radio, signal processing, and computing come together in a shared experimental environment.

01 / DEVELOP

Bring your ideas to the signal.

Implement waveforms, study algorithms, and move between software models and radio experiments.

02 / CONNECT

Work across the whole system.

Combine radio equipment, network functions, and accelerated computing to explore end-to-end behaviour.

03 / EVALUATE

Make experiments count.

Use controlled scenarios and measurements to understand performance, compare approaches, and refine your design.

03 / Experimental infrastructure

The infrastructure.
From radio to orbit.

Software-defined radios, signal processing, satellite channel emulation, and a co-located teleport form a connected environment for communications experiments.

16 software-defined radios. Five USRP models.

Product images: Ettus Research / NI. Manufacturer references, rather than photographs of individual CTTC units.

Keysight PROPSIM FS16

Channel emulator with Satellite and Aerospace toolboxes for NTN emulation across LEO, MEO, and GEO scenarios.

PROPSIM FS16 · equipment reference

COMPUTE & ACCELERATION

Signal processing, AI & edge

8Servers for signal processing
1AI cluster with NVIDIA GPUs
4NVIDIA edge computers

MOBILE NETWORK SYSTEMS

Network and terminal systems

1Mobile network callbox
1Commercial UE platform

Network and terminal platforms for end-to-end experimentation.

FIXED GROUND SEGMENT

Ku-band GEO access

2Fixed 2.4 m Ku-band antennas for GEO

A fixed satellite ground-segment resource alongside the platform’s tracking antennas.

MULTIBAND GROUND SEGMENT

LEO / MEO / GEO antennas

1UHF & S-band antenna for LEO / MEO / GEO
1Ku, Ka & Ka-mil band antenna for LEO / MEO / GEO

CONNECTED FACILITIES

Co-located teleport

A co-located teleport connects the ground segment to the experimental infrastructure through radio-over-fiber.

Explore the SpaceLab stack ↗

The wider CASTLE platform also supports mmWave antenna-array research, visible light communications, MATLAB-compatible signal exports, and AI/ML workflows.

Ground segment / On site at CTTC

See the hardware.

Four views of the rooftop antenna installations and tracking dish.

Satellite tracking dish on the CTTC rooftop — Tracking dish and mountCTTC facility photograph · Open image for the full-size view

Close-up of the tracking dish reflector and feed assembly — Reflector and feed assemblyCTTC facility photograph · Open image for the full-size view

Front view of a CTTC tracking dish — Tracking antenna, front viewCTTC facility photograph · Open image for the full-size view

04 / Connected systems

Experiment beyond
a single link.

Connect the physical layer to the wider network. CASTLE brings terrestrial, satellite, and optical wireless experimentation into a common research environment.

Watch the platform overview

Terrestrial networks

5G NR and LTE research, with end-to-end over-the-air experimentation.

Satellite & hybrid networks

Satellite waveform research, including DVB-S2X and BGAN, alongside hybrid terrestrial–satellite scenarios.

Software-led workflows

Signal generation, data capture, processing, and analysis connected through cloud-based tools.

05 / Research in action