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bg2uey 发表于 2011-2-12 14:10

流星雨0724 发表于 2011-2-12 14:04 static/image/common/back.gif
一个中继的接收信号范围与发送信号范围是不是一样

是的~~~~~~

yangzhe1991 发表于 2011-2-12 14:10

维基百科查的：
A disadvantage of using CTCSS in shared frequencies is that since users cannot hear transmissions from other groups, they may assume that the frequency is open when it is not and transmit simultaneously with another user, thus accidentally overriding or interfering with the other group's transmission. For example, in the above situation a landscaper might be communicating with another landscaper. Meanwhile, a pizza delivery driver—not hearing any transmissions—assumes that the frequency is clear and calls his dispatch office. Depending on several factors (locations, power, etc.), the two simultaneous transmissions could easily interfere with each other—resulting in one or both not being clearly understood. The more separate groups that share a single frequency and the more frequently that they transmit, the more likely that this accidental interference will occur.
感觉这题出的有毛病啊………………

bg2uey 发表于 2011-2-12 14:12

joyce90829 发表于 2011-2-12 14:09 static/image/common/back.gif
回复 bg2uey 的帖子

楼主说一般step为12.5khz,那这个题目里145到148MHZ共有多少上下行频率对呢？比如这个上 ...

可以这样理解，但是step步进也可以设置成别的值，但是题目里却没有要求。。

bg2uey 发表于 2011-2-12 14:12

mandylh 发表于 2011-2-12 14:09 static/image/common/back.gif
啥也不说了 谢谢楼主

祝取得好成绩~

bg2uey 发表于 2011-2-12 14:14

云枫梦泽 发表于 2011-2-12 14:09 static/image/common/back.gif
楼主，看了前面的对我帮助很大，非常感谢~
想请教楼主：
1.本题如果用最小覆盖算法来解，那么PL的应用是 ...

如果一个城市中继无干扰，则可以不设置中继，如果被杂波干扰，则需要设置亚音，以防止中继因干扰而长时间转发，烧坏发射机

bg2uey 发表于 2011-2-12 14:15

云枫梦泽 发表于 2011-2-12 14:09 static/image/common/back.gif
楼主，看了前面的对我帮助很大，非常感谢~
想请教楼主：
1.本题如果用最小覆盖算法来解，那么PL的应用是 ...

我说过了，大连zj，可以覆盖到山东，怎么说也100多公里了吧？
高度决定一切，再次重申

dannydoggygouch 发表于 2011-2-12 14:16

对于原题上面对信道的划分有疑惑。。我的理解是直接用0.6做间距。。但是队友认为是output: 145.100 to 145.500 MHz input: 144.500 to 144.900 MHz
146.610 to 147.000 146.010 to 146.400
147.000 to 147.390 147.600 to 147.990；

请问哪个对呢。

小舜子 发表于 2011-2-12 14:19

楼主，用户会不会向中继站发送频率？

bg2uey 发表于 2011-2-12 14:19

yangzhe1991 发表于 2011-2-12 14:10 static/image/common/back.gif
维基百科查的：
A disadvantage of using CTCSS in shared frequencies is that since users cannot hear  ...

所以我果断放弃这题。。

bg2uey 发表于 2011-2-12 14:20

dannydoggygouch 发表于 2011-2-12 14:16 static/image/common/back.gif
对于原题上面对信道的划分有疑惑。。我的理解是直接用0.6做间距。。但是队友认为是output: 145.100 to 145. ...

应该是你队友的正确，题里的0.6指的上下行频率差~

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