| dc.description.abstract | Synthetic aperture radars (SAR) is an active microwave sensor widely used in earth resources exploration, global hazards detection, environmental change detection and other applications due to its all weather operation capability. Linear frequency modulated pulses are used as transmitted signal by conventional SAR. However, the pulse SAR systems are not suitable to be carried by light platforms, because they must use big power generator to produce necessary high power pulses. Linear frequency modulated continuous wave (LFM-CW), on the other hand, is able to achieve high performance with smaller structures and lower cost.
This thesis focuses on the design and test of a LFM-CW SAR, followed by de-signing a novel image focusing algorithm for it. In order to verify the system archi-tecture, well-controlled instruments, RF circuits and computer are utilized throughout the design and construction of the system. In the test, a signal generator is used to generate chirp source fed to the RF circuit including antenna for transmitting. The re-ceived signal is then demodulated to baseband and stored for further SAR processing. The analysis of the image quality is performed through a series of field tests. It is demonstrated that the system is able to achieve the required specifications.
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