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标题: 晒introduction 求意见 [打印本页]

作者: 游戏人生 时间: 2011-2-14 22:57
标题: 晒introduction 求意见

Given the popularity of repeater, lots of researches have been done to improve the range, Interference and other factors of it. Besides, radios enthusiasts’ organizations from all over the world such as HAM from China and ARCC from U.S.A offer lots of help in how to use repeaters in specific steps. Nevertheless, not much work has been done when respect to the problem of how to determine minimum number of repeaters if simultaneous users, area, spectrum available and PL tones are given.

Faced with this problem, frankly speaking, we are totally confused by the phase “simultaneous users”.

1,000 simultaneous users, possible?

Firstly, we assume it means 1,000 users could talk with each other in the given area like they do when use mobile phone. Yet we soon find out that it is not possible since normal repeater only allows single user to “talk”, which means 1,000 users need at least 500 repeaters to accommodate 500 couple of conversation at one moment. Evidences are obvious in reality: interphone is used in group case rather than person to person case in which cell-phone and other devices work much better.

Dozens of hours of waiting time, acceptable?

Secondly, we assume that an appropriate waiting time can be regarded as simultaneity from the view of microscopic. After estimating we get the unbelievable result: if waiting time is as short as one minute on average when all 1,000 users want to speak, more than thousands repeaters are needed. On the other hand, if the number of repeater is limited within normal level such as ten, the waiting time can reach dozens of hours. What about 10,000 users? Forget it. Actually, the case that 1,000 users in one city want to speak at one specific moment will never exist!

Much noise when use repeater as connector, Tolerable?

Thirdly, we assume it means when one user “talk”, users from the given area, wherever, can receive the signal if they want. Unfortunately again, it is proved to be impossible neither. After consulting repeater producers and checking information of what repeater used for, we are informed that repeater’s passing information from one area to another is not allowed even, let alone encouraged. In other words, one repeater’s major job is to amplify and retransmit signals to users within its range rather than pass them to another repeater for two-area’s connection. If only using repeaters for connecting from great distance, lots of extra repeaters will be required and consequently, producing huge Interference. This is also truthfulness since nobody wants to connect others from 90 miles away by interphone, they can use cell phone or other modern facilities instead.

Our goal, practical and reasonable!!!

Excluding all the ridiculous and unpractical ideas and analyzing the specific theory of repeater, we ultimately clear our goals:

·
How to divide the whole given area into parts that each can be covered by one repeater with minimum number of repeaters.

·
How to mitigate the Interference between repeaters to lowest extent

·
How to improve users’ Telecommunication Quality to highest extent

·
Determine the specific location, PL tones and frequency points of each repeater

·
When the terrain become complex, such as mountainous area, how to assign repeaters then

作者: 月之光 时间: 2011-2-15 00:06
回复游戏人生的帖子

LZ，神人！怒我直言，求summary.求strengthes and weaknesses,求references，求model,求table

作者: 月之光 时间: 2011-2-15 00:09
回复游戏人生的帖子

另外，Firstly, we assume it means 1,000 users could talk with each other in the given area like they do when use mobile phone，貌似是when using?

作者: 游戏人生 时间: 2011-2-15 01:12
回复月之光的帖子

看得这么仔细，十分感谢！惭愧的是summary.求strengthes and weaknesses,求references都米写啊……model table咱们相差巨大没啥用额

作者: ABCF 时间: 2011-2-15 01:59
跟LZ模型有点相同~大胆写吧~

作者: ABCF 时间: 2011-2-15 02:01
回复 ABCF 的帖子

嗯，LZ还是仔细考虑哈，好像只有很少队数目那么多~

作者: 笑沧海DJ 时间: 2011-2-15 03:22
够犀利，我们也是瞎写的

作者: 游戏人生 时间: 2011-2-15 04:07
回复 ABCF 的帖子

我们没说我们的数目多少啊……

作者: ABCF 时间: 2011-2-15 06:18
窗口打开多了，回复出错了，不好意思~

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