Advancement of atmospheric research tools

This thesis describes contributions made to improve atmospheric research tools through implementation of modern technologies on existing instruments. The dynamic changes in the atmosphere are ever more evident and the need to monitor them have risen in recent years. To effectively observe these changes, existing atmospheric research tools must be enhanced to provide extended data from different parts of the atmosphere in the form of higher quantity and quality. The computational power of modern electronics are enabling the transition from the analog to the digital realm to progress closer to the physical processes. By doing so, the power of digital signal processing is increasing the capabilities of research tools vastly. New research disciplines that were not achievable in the analog domain are rediscovered and realized in the digital domain. Increased computational power also enables the implementation of more intelligent instrument softwares, allowing applications previously limited to hardware to be implemented in software. The benefit of software realization is, in addition to improved signal processing capabilities, a substantial reduction of upgrade cost, regardless of the reason for the upgrade. In this thesis, it is shown that communication with stratospheric balloons can be improved by implementing an antenna pointing system to provide more bandwidth and range for real-time data acquisition, thus offering more rapid data recovery. This is shown by replacing the existing omni-directional antenna onboard stratospheric balloons with an antenna with a narrower beam, and thereby increase the antenna gain by 260 times. This gain can be used in a trade-off between higher data rates, longer range, and lower weight. It is also shown that by combining the use of band-pass sampling, to reduce data rates, and true time-delay beamforming, realized with FIR-filters, to encapsulate the wide band-width of Incoherent Scatter Radar signals, Large Aperture Array Radars are made feasible. This enables multiple simultaneous beams to be produced, permitting the dynamic behavior of the ionosphere the be recorded through instantaneous observation of multiple volumes of the ionosphere. In consequence of this, the author claims that these improvements lead to increased data quantity and quality, which is the first step toward improved knowledge and understanding of our atmosphere. The importance of that understanding is indisputable; we only have one atmosphere and it affects us all equally.Godkänd; 2007; 20070316 (ysko)