您好!中继台与中继台之间的干扰据说可以使用亚音频技术解决?那亚音频是如何减少其干扰的?问题的背景如下:Problem:Repeater Coordination The VHF radio spectrum involves line-of-sight transmission and reception.
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您好!中继台与中继台之间的干扰据说可以使用亚音频技术解决?那亚音频是如何减少其干扰的?问题的背景如下:Problem:Repeater Coordination The VHF radio spectrum involves line-of-sight transmission and reception.
您好!中继台与中继台之间的干扰据说可以使用亚音频技术解决?那亚音频是如何减少其干扰的?
问题的背景如下:Problem:Repeater Coordination
The VHF radio spectrum involves line-of-sight transmission and reception.
甚高频无线电频谱包含信号的发送和接受.
This limitation can be overcome by “repeaters,” which pick up weak signals,amplify them,and retransmit them on a different frequency.
这种限制可以被中继站所克服.中继站可以捕捉到微弱的信号,然后把它放大,再用不同的频率重新发送.
Thus,using a repeater,low-power users (such as mobile stations) can communicate with one another in situations where direct user-to-user contact would not be possible.
这样,低功耗的用户,例如移动电话用户,在不能直接与其他用户联系的地方可以通过中继站来保持联系.
However,repeaters can interfere with one another unless they are far enough apart or transmit on sufficiently separated frequencies.
然而,中继站之间会互相影响,除非彼此之间有足够远的距离或通过充分分离的频率来传送.
In addition to geographical separation,the “continuous tone-coded squelch system” (CTCSS),sometimes nicknamed “private line” (PL),technology can be used to mitigate interference problems.
除了地理的分离、“连续编码音调控制系统”(CTCSS),有时被称为“私人专线”(PL)、这项技术可以用来减轻干扰问题.
This system associates to each repeater a separate subaudible tone that is transmitted by all users who wish to communicate through that repeater.
该系统连接每个中继站,靠的是所有通过同一个中继站连接的用户发送的独立的亚音频音调来连接.
The repeater responds only to received signals with its specific PL tone.
中继站只回应接收到的具有特殊PL的语调的信号.
With this system,two nearby repeaters can share the same frequency pair (for receive and transmit); so more repeaters (and hence more users) can be accommodated in a particular area.
通过这个系统,两个附近的中继站可以共享相同的频率对(包括接收和发送);对于更多的中继站(今后更多的用户)可以安排在一个特定的区域.
For a circular flat area of radius 40 miles radius,determine the minimum number of repeaters necessary to accommodate 1,000 simultaneous users.
在一个半径40英里的圆形区域,请你设计一个方案,用最少量的中继站来容纳1000同时在线用户.
Assume that the spectrum available is 145 to 148 MHz,the transmitter frequency in a repeater is either 600 kHz (=0.6MHz) above or 600 kHz below the receiver frequency,and there are 54 different PL tones available.
假设频谱范围是145到148兆赫,在中继站中的发射机的频率要么比接收机频率高600千赫以上,要么低600千赫以下,并且这里有54个不同的PL可用.
How does your solution change if there are 10,000 users?
如果有10,000个用户,你的方案如何更改?
Discuss the case where there might be defects in line-of-sight propagation caused by mountainous areas.
由于山区会阻碍信号的传播,讨论这样的情形.
您好!中继台与中继台之间的干扰据说可以使用亚音频技术解决?那亚音频是如何减少其干扰的?问题的背景如下:Problem:Repeater Coordination The VHF radio spectrum involves line-of-sight transmission and reception.
这道题目我是这样理解的~54个亚音频相当于54种不同颜色的帽子~然后就相当于给每个传输中的信号带了帽子~
然后每个中继器只能接一个特定颜色的帽子~可以传出别的颜色的帽子的给别的中继器~
本来假如信号按频率分总共有84种信号~再给每个频率的信号带帽子,可以带成84种样子~所以就可以相当于信号总的分成84*54种了~--------还有~我觉得MCM结束了啦~可以好好休息准备开学啦~^ ^
.......................就是相当于你讲话的时候加密了,不让别人听见!