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Projecte llegit

Títol: Desenvolupament d'un Radiotelescopi de Ràdio Definida per Programari (SDR): Disseny físic i Anàlisi del Sistema

Estudiants que han llegit aquest projecte:

Director/a: GUTIÉRREZ CABELLO, JORDI

Departament: FIS

Títol: Desenvolupament d'un Radiotelescopi de Ràdio Definida per Programari (SDR): Disseny físic i Anàlisi del Sistema

Data inici oferta: 05-02-2026     Data finalització oferta: 05-10-2026


Estudis d'assignació del projecte:
    DG ENG AERO/SIS TEL
Tipus: Individual
 
Lloc de realització: EETAC
 
Segon director/a (UPC): GELONCH BOSCH, ANTONI
 
Paraules clau:
Radiotelescopi, Antena, Disseny, Programari
 
Descripció del contingut i pla d'activitats:
This thesis is devoted to the design, implementation, and characterization of a low-cost, high-flexibility radio telescope utilizing Software-Defined Radio (SDR) technology.

Traditional radio astronomy instrumentation often relies on expensive, application-specific hardware that lacks the adaptability required for multi-purpose astronomical observations.

By leveraging the versatility of SDR, this project aims to democratize access to radio astronomy for educational and small-scale research environments.

The system architecture consists of a parabolic reflector antenna and a high-sensitivity feedhorn optimized for observations in the range spanning from MHz to a few GHz. The signal chain incorporates a low-noise amplifier (LNA) and a bandpass filter to mitigate terrestrial interference before digitizing the signal via an RTL-SDR or similar high-bandwidth SDR platform.

The core of the project focuses on the development of a digital signal processing (DSP) pipeline. This software layer performs integration, and baseline subtraction. Calibration will
be conducted using the "hot/cold" method, utilizing the ground and the empty sky as thermal references to determine the system's equivalent noise temperature.

A design requirement is that the entire system should be prepared to facilitate the incorporation of interferometry mechanisms.

Work Plan
1) Antenna and pointing subsystems physical design
2) Subsystems development and integration
3) Performance system analysis
 
Overview (resum en anglès):
Amateur radio astronomy opens a window to the exploration of the invisible universe, allowing the observation of phenomena such as the emission of the neutral hydrogen line at the 1420 MHz frequency. However, this practice is often limited by the high cost of commercial astronomical pointing and tracking systems. To address this issue, the main objective of this Bachelor's Thesis is the design, construction, and initial validation of a low-cost automated altazimuth mount. The project adopts a multidisciplinary approach, typical of a double degree, integrating solutions from mechanical engineering, electromagnetic design, power electronics, and software engineering.

Regarding the mechanical methodology, the structure has been conceived by combining the rigidity of metal with the flexibility of additive manufacturing. The main chassis has been constructed by assembling 114 aluminum bars to ensure the optimal alignment of the antenna under load. The connection nodes and transmission mechanisms have been manufactured using 3D printing with ASA (Acrylonitrile Styrene Acrylate) polymer, ensuring mechanical strength and immunity to ultraviolet radiation degradation. To minimize positioning error, double helical gears (herringbone) have been designed. In the field of radio frequency, the methodology has included the theoretical calculation and physical fabrication of a cylindrical feeder and its ground plane, optimized for resonance in the 21 cm band.

In the control section, the architecture employs NEMA 23 stepper motors managed by an Arduino microcontroller, using the AccelStepper library to generate smooth mechanical acceleration profiles. The software system has been developed in Python, creating a graphical user interface and implementing an asynchronous architecture based on execution threads to ensure seamless communication with the hardware. Astronomical tracking has been resolved through the automated calculation of celestial trajectories using the Skyfield mathematical library.

Finally, regarding the obtained results, the fabrication of the base mechanical and electromagnetic subsystems has been successfully completed. Although unforeseen logistical delays in the supply of the main structural support and the reception chain-specifically the LNA amplifier and SDR receiver-have prevented the final assembly and electromagnetic characterization under real load, the viability of the project has been demonstrated. Bench tests (under no-load conditions) have allowed for the comprehensive validation of the entire control logic, the bidirectional data flow, the calculation of celestial coordinates, and the response of the electromechanical actuators. The work achieves its purpose by providing a robust, modular, and logically fully operational technological base, completely prepared for its definitive mechanical integration.

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