期刊文献+
共找到1篇文章
< 1 >
每页显示 20 50 100
Methods to Improve the Long Distance Time-Varying Channel Transmission Performance of Expendable Profiler
1
作者 ZHENG Yu ZHANG Xiao-yang +2 位作者 WANG Xiao-rui GUO Xing-xin LI Hong-zhi 《China Ocean Engineering》 SCIE EI CSCD 2019年第6期753-761,共9页
To improve the transmission performance of XCTD channel, this paper proposes a method to measure directly and fit the channel transmission characteristics by using frequency sweeping method. Sinusoidal signals with a ... To improve the transmission performance of XCTD channel, this paper proposes a method to measure directly and fit the channel transmission characteristics by using frequency sweeping method. Sinusoidal signals with a frequency range of 100 Hz to 10 k Hz and an interval of 100 Hz are used to measure transmission characteristics of channels with lengths of 300 m, 800 m, 1300 m, and 1800 m. The correctness of the fitted channel characteristics by transmitting square wave, composite waves of different frequencies, and ASK modulation are verified. The results show that when the frequency of the signal is below 1500 Hz, the channel has very little effect on the signal. The signal compensated for amplitude and phase at the receiver is not as good as the uncompensated signal.Alternatively, when the signal frequency is above 1500 Hz, the channel distorts the signal. The quality of signal compensated for amplitude and phase at receiver is better than that of the uncompensated signal. Thus, we can select the appropriate frequency for XCTD system and the appropriate way to process the received signals. Signals below1500 Hz can be directly used at the receiving end. Signals above 1500 Hz are used after amplitude and phase compensation at the receiving end. 展开更多
关键词 expandable conductivity temperature depth(XCTD)profiler time-varying channel modeling frequency sweeping method amplitude and phase compensation transmission performance
下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部