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How larger bandwidth serves better?

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EngIntoHW

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I'd like to understand the advantages of transferring data (wirelessly) over a larger bandwidth.

Bandwidth sets the rate of data which are being transferred from a transmitter to a receiver, and not the amount of data which is being transferred (as the amount of data depends on the time duration the data is being transmitted).

How does haveing larger bandwidth help in transferring voice (which has a limitted baseband bandwidth) in a cellular network?

I think that one of the reasons is that larger bandwidth allows transferring the same code (which contains the voice) in less time (as the data transfer rate is larger):
=> The network is loaded for less time.
=> The voice reaches its destination faster.
=> larger code (=> less noise) could be used without increasing the transfer time.

Am I right about these 3 points?
Any more advantages you can think of?

Thank you :)
 
The cellular market for voice calls is fairly well saturated. The UK, with 60 million people, had approximately 70 million active cell phones a couple of years ago.

The cellular companies are trying to use their expensive networks for other things. For example, the iPad 3G is selling quite well and can't make a voice call. I designed vehicle tracking devices that had no connection to the audio circuits as it could only use texts and GPRS data.

All those data uses need more bandwidth for faster download times, to either give faster browsing, or to allow more users on each cell.
 
Thank you very much Diver! :)

The cellular market for voice calls is fairly well saturated. The UK, with 60 million people, had approximately 70 million active cell phones a couple of years ago.

The cellular companies are trying to use their expensive networks for other things. For example, the iPad 3G is selling quite well and can't make a voice call. I designed vehicle tracking devices that had no connection to the audio circuits as it could only use texts and GPRS data.

All those data uses need more bandwidth for faster download times, to either give faster browsing, or to allow more users on each cell.

Regarding your last sentence.
in WCDMA-FDD protocol, all users transmit over 3.84MHz bandwidth of each 5MHz channl's bandwidth, am I right?
However, in this protocol, Uplink and Downlink use different frequencies (that's where the FDD is involved), don't they?

If so, having larger bandwidth, means that more channels can be used, therefore more users can be connected without increasing the noise level, is that so?
 
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It's now possible to have cellular connections where the users are permanently connected with an IP address, like computers on a LAN. Data can be sent either way. Having more bandwidth means that the data will get through faster, so the users will spend less time using cell, so more users can be supported.
 
Got it, thank you :)

I'm sorry for asking this stupid basic question, I'm really curious abou it.
the users will spend less time using cell, so more users can be supported


I could understand the restriction of users' quantity, if TDMA or FDMA were in use, as for TDMA, there's a limitted amount of time-slots to allocate for users, and as for FDMA, there's a limitted amount of frequencies to allocate for users.
But having WCDMA, which allows users to share the same bandwidth at the same time, what restricts the amount of users transmitting overa given bandwidth?

Is it not having enough code to encode each user and keep its data nearly orthogonal to other users' data?
 
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Eng, regardless of how the data is encoded every slot uses some bandwidth, if your channel uses 1mhz you can only fit 10 in use channels in a 10mhz spectrum. It doesn't matter how many logical chanels are asigned to a given bandwidth it can only contain as much data as the spectrum band it's in. Once enough in use channels consume the available bandwidth further channels will get left without a connection, the WCDMA protocal can't make bandwidth out of nothing, it's a slick protocol but it's not magic =) So while cell phone towers can be in contact with hundreds or thousands of cell phones because the identification and control protocols use little bandwidth every phone in a cell can't make a call at the same time (in a densely populate cell), there isn't enough bandwidth.
 
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