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Serial Interface and QPSK

hello to all,,,

i just want to know how to make relation between router interface clock rate and QPSK symbol capacity...mean to say if i am having router which is not wireless and if i want to send data in wireless form and i am having QPSK converter and having transmitter on both the end so at that time how we can consider clockrate with the QPSK capacity...




Re: Serial Interface and QPSK

There really is no relationship. What you'll see is a device (like a radio transceiver) that will do a certain amount of bandwidth over the wireless link,

On the other side of our hypothetical "black box" transceiver, you'll get some flavor of standard interface; either an Ethernet/Fast Ethernet/Gig Ethernet or (a little closer to your question) a standard serial interface that'll probably be presented on a v.35 / Winchester connector.

That interface will (probably) be a DCE interface (or maybe several), just like a CSU/DSU (because it probably is that or something similar).

The "black box" will do the signal conversion from serial / V.35 into whatever signaling it uses to make the wireless transmisssion.

In the case of a traditional microwave radio, it was fairly common for them to handle up to three DS3s (45 Mbps each).

So what I'd expect is that if you had a radio system that could handle ~2 Mbps, you'd probably have a single V.35 interface that'd handle a T1/DS1 or E1.

If you had a radio that could handle 1.2 Gig of data wirelessly, then I'd expect a GigE inerface, or perhaps one or more OC3, or an OC12.

There are a variety of wireless systems in practically all bandwidth sizes, on just about any chunk of the RF spectrum, up to and including light (LASER - see the Canon Cannobeam).

Once the wireless bandwidth is deterined, then the router-side interface will be appropriate for that kind of bandwidth.

Good Luck