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电子工程专辑
2 年
VHF和UHF信号视距传播距离计算器
特高频(UHF,也称分米波)在我国的频率范围是470MHz~806MHz 30MHZ以下的短波段(HF段)无线电信号是依靠电离层的反射进行远距离的传播,传播的距离可以由数百公里至上万公里,由于电离层本身的特殊性,正常情况下电离层对高于40MHZ的无线电信号的反射是很 ...
来自MSN
4 个月
夜鹰号发射成功!镭洋与太空中心合作首颗3U通信立方卫星升空
并有海内外多位UHF无线电用户成功接收到夜鹰号卫星发出的beacon信号。 夜鹰号为镭洋科技参与国家太空中心创业公司追星计划任务,以创建台湾卫星 ...
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