某局投诉有一个基站手机信号波动严重，局方维护工程师在某处用测试手机实测接收信号有－90dbm，但是有时甚至会达到20几个dbm的波动。办事处工程师小H接到任务后前往现场进行处理，并且做出了一系列判断定位，请协助对办事处工程师的判断做出分析。
首先根据波动现象初步分析，小H认为可能是弱信号覆盖或孤站的边缘覆盖，造成信号波动现象，你认为他的判断有道理吗？为什么？
参考答案：这种判断是正确的。因为信号的传播存在直射、绕射、反射等多种形式，多径传播造成接收点的信号强度是时变的，尤其是弱信号时从手机上更能够反应出信号的波动存在。
第二节摘录信息（共5小题；每小题1分，满分5分） 阅读下面短文，根据所读内容在文后第53至第57小题的空格里填上适当的单词或短语，并将答案转写到答题卡上。 注意：每空不超过3个单词。 You’re listening to Radio Five. Regular listeners know that every Thursday I give a list of places in the city that are looking for volunteers. Perhaps you’d like to get a pencil and write down the ones that interest you. Tiny Tot Preschool is looking for someone who will sing songs to the children on Tuesday mornings. The best person for the job would be someone who can play the piano or guitar. Primary School 39 needs volunteers to tutor students in English after school on Mondays, Wednesdays and Fridays. If you are good at English, that is a great chance. The Parks Department needs volunteers to help clean up the parks before National Day. If you like to work outdoors and help the environment, this job is for you. Lastly, the Community Center is looking for volunteers to work with older people on weekends. You can help read and write letters for seniors with bad eyesight. The Center also needs a few students to do fix-up work on houses. If you often help your grandfather repair his house, perhaps this is the perfect job for you. If you are interested in any of the jobs, you can call us at 5488-2377. People need your help. Volunteer today! Let’s be volunteers!
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