Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2011. / ENGLISH ABSTRACT: The objective of the thesis is the development of a phase noise measuring system that makes use of crosscorrelation and averaging to measure below the system hardware noise floor. Various phase noise measurement techniques are considered after which the phase demodulation method is chosen to be implemented. The full development cycle of the hardware is discussed, as well as the post processing that is performed on the measured phase noise. / AFRIKAANSE OPSOMMING: Die doel van hierdie tesis is die ontwikkeling van ’n faseruis meetstelsel wat gebruik maak van kruiskorrelasie en vergemiddeling om onder die ruisvloer van die meetstelsel se hardeware te meet. Verskeie faseruis meettegnieke word ondersoek en die fase demodulasie metode word gekies om geïmplementeer te word. Die volle ontwikkelingsiklus van die hardeware word bespreek, sowel as die naverwerking wat toegepas is op die gemete faseruis.

This thesis investigates the possibility of detecting weak vital signs, such as heartbeat and respiration rate, through the implementation of quadrature demodulation and frequency spectrum algorithms on a high performance digital signal processor. This thesis has been part of an ongoing research project at Linkoping University, with the aim to develop a sensor platform for wireless measurements of these vital signs. This sensor platform has been expected to consist of two major physical devices, a RF-radar front-end including a quadrature multi-port and a processing back-end which holds the implementation of the algorithms to detect the vital signs. The back-end consists of a data acquisition- and a processing-part which together forms the digital signal processor. The results show that the implemented algorithms works in terms of being able to find artificial vital signs from quadrature signals. This result also confirms that the hardware solution proposed during this thesis, has been considered as viable for the aim of the project.