TY - THES A1 - Dogotari, Marcel T1 - Hardware Design and RF Performance Evaluation of a Long Range 2.4 GHz Radio Module N2 - Low–power, long–range wireless solutions are needed for transmission of environmental and industrial monitoring data from remote, battery–driven sensors. Chirp spread spectrum (CSS) modulation techniques are able to meet these requirements. A CSS–based radio module was designed to operate in the 2.4 GHz frequency band, whose advantages are worldwide availability, lack of duty–cycle restrictions and a broad spectrum. The module’s power consumption is satisfactory, but its range has to be improved. The accuracy of time-of-flight (ToF) distance estimation, an extra feature of the module, has not been evaluated. Impedance matching, transmission lines and printed circuit board design are among the practical aspects discussed, while ToF ranging and orthogonality of CSS signals are considered from a theoretical point of view. KW - Long–range radio module KW - Printed circuit board design KW - Transmission lines and impedance matching KW - Chirp spread spectrum KW - Time-of-flight ranging Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:1383-opus4-2158 ER - TY - THES A1 - Lam, Hoi Ying T1 - Radar Signal Distortion caused by Directional Vibration of a 24 GHz FMCW System N2 - This thesis is an initial attempt to investigate the influence of mechanical vibrations on the 24 GHz FMCW radar developed by IMST GmbH and develop a simple vibration compensation model for the human tracking algorithm. The project objectives are to determine the radar signal distortion caused by vibrations theoretically, conduct simulations to evaluate the effects of vibrations on the human tracking process, and develop a basic model to compensate the disturbing vibrations. The single radar pulse simulations conclude that when the radar is vibrating at a low frequency, the signal would not be distorted if the change of phase of the intermediate frequency is less than half a resolution cell. While the results from the multiple radar pulses simulations reveal that factors like the SNR value, vibrating amplitude and the target’s velocity would influence the human tracking process. The higher the SNR value, vibrating amplitude and target’s velocity, the more the detected ghost targets when there is only one target presence. A signal demodulation method is then proposed which indicate the possibility in reducing the disturbance caused by the vibrations. KW - FMCW Radar KW - Vibration KW - Human Tracking KW - Simulation KW - Compensation Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:1383-opus4-2164 ER -