Summary: | 碩士 === 國立臺灣科技大學 === 電子工程系 === 95 === In this thesis, one long-haul over the sea surface microwave radio link is analyzed and the measurement requirement is proposed, such that a high capacity (STM-1) and high speed (171Mbps) transmission design can be realized. The analysis of sea reflection coefficient, the obtained high-gain pattern and the analysis between the K-value change and the receiver signal level fluctuation are all the factors to decide the optimal antenna height and spacing. Therefore, the uncorrelated signals can be obtained between the main and diversity antenna and the simultaneous cancellations of signals can be avoided.
The quality of installation for Antenna/Waveguide system plays a very important role since it will generate echoes to result in the ISI appearing on receiver input if there is any impendence mismatch occurred in the conjunction. The measurement requirement derived from radio echo requirement for satisfying specification is proposed. In addition, the interference to cause receive sensitivity degradation is also discussed in this thesis.
The measurement records show that the increasing output power will not alleviate the multipath fading effect suffered by receiver. The use of diversity and time domain adaptive equalization (TDE) have been found to greatly mitigate the effects of dispersive fading, allowing performance objectives to be met for digital radio. The prediction models for multipath channels show that the performance of equalization technology has a great impact on the result of outage probability.
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