【判断题】定向天线,在在水平方向图上表现为一定角度范围辐射,也就是平常所说的有方向性,在垂直方向图上表现为有一定宽度的波束,同全向天线一样,波瓣宽度越小,增益越大。()
【判断题】定向天线,在水平方向图上表现为一定角度范围辐射,也就是平常所说的有方向性,在垂直方向图上表现为有一定宽度的波束,同全向天线一样,波瓣宽度越小,增益越大。()
【简答题】阅读下文并回答问题。 People often like collecting things. Collecting stamps, books, pictures and pens are some common hobbies. I know many kinds of collections, but the strangest is a collection of clocks. My f...
【简答题】I’d like to tell you about my dream classroom in the future.My classroom will be very 31 ,so we can do lots of activities in the classroom.In summer,it will be 32 and in winter it will be warm,so it w...
【简答题】People often like collecting things. Collecting stamps, books, pictures and pens are some common hobbies. I know many kinds of collections, but do you know the collection of clocks? My friend Mr. Cloc...
【简答题】完型填空。 There is a shop near my home. It (1) many things like bread, milk, (2) and drinks. My mother often goes shopping there (3) Sundays and buy food. I go with her, too, and carry baskets (4) her. Th...
【判断题】全向天线,即在水平、垂直方向图上表现为360°都均匀辐射。