Lauzin, ClémentLederer, DimitriCollignon, SimonSimonCollignon2025-05-142025-05-142025-05-142022https://hdl.handle.net/2078.2/27762With its outstanding ability at probing a frequency range larger than 10 GHz in one acquisition, the chirped-pulse Fourier transform spectrometer has revolutionized the field of gas phase microwave spectroscopy. The pure rotational spectra collected by this instrument display a high-resolution and reach high-sensitivity levels by virtue of the phase-reproducible chirped-pulse measurements. With the ever-growing advances in digital electronics, it is now manageable to perform the chirp generation with a direct digital synthesizer and the detection of the molecular emission with a digitizer card or a USB oscilloscope. In this work, a spectrometer that includes both of those features is presented. The instrument aims to explore the Ku-band of the microwave range, where the molecular sample is investigated either in a waveguide static cell or in a supersonic jet expansion. To this end, the instrument is characterized and optimized with the development of a fast averaging scheme and a post-processing pipeline. For the supersonic jet expansion experiment, we present a novel approach to optimize the sensitivity of the instrument by polarizing the molecular beam through a slotted waveguide.CP-FTMWtext::thesis::master thesisthesis:37229