Digital wireless systems

Apparently not.

Sure, if we are looking for a $200 solutions, we can build multi-TX,RX radios. We don't have to deal with channels and/or routings as well.

Yep. Too bad the O.P. here seems to have disappeared!

Hi,

So, I need customized hardware to do this. Are you guys sure that there are no chips available to do what I want to do? Any suggestions or pointers that how should I proceed. I have FPGA generated clock and data stream . Data is 48 bits wide and I am serially outing the data at 1.5MHz.

Regards, John

So you are dealing with 1.5Mbps. In theory, 5.8GHz 802.11n can handle it. But with all the overheads of channellings and routings, it will not guarantee the data rate. Your FPGA would have to talk ethernet/TCP/IP in this case. You can bump it up with Multi- Transceivers as another poster suggested, but it will not be cheap. Your best bet is to do a simple modulation/protocol at 5.8GHz.

What's the actual required throughput? Could you bring the 48 bits into a FIFO and send them out at a slower (cheaper, easier to find) rate?

Hi,

Okay , What is the slower , achievable rate? I can try to slow the data rate down to that value

John

Frank

My understanding is that the internal data path is 48 bits, but the serial clock rate is 1.5MHz or 1.5Mbps. Either way, he need a custom solution. If I am right, it would be a cheap custom solution. If you are right, it would be an expensive custom solution.

Yep, it looks like 1.5 Mbps as you said. I wonder why no wires? 6 feet looks like such a short range for wireless, especially RF wireless. Since it's apparently only 1.5 Mbps, I'd consider something simple, like FM carrier at 2.4 or 5.8 GHz, Manchester coded. That would double the BW, but improve the SNR. It's still cheap and simple. I'd publish a 1.5 Msps demodulator in Verilog for the right kind of beer ;-). The up/downconverter is up to the OP.

Frank

He says he is "serial outing the data ay 1.5 MHz" . He needs to explain better what he is doing or intends to do. Otherwise this thread is a "waste of bandwidth".

We need the OP back for sure. If he is really from Wayne State University Medical Center, perhaps isolation issues from the operating room?

Hi,

I am looking for a digital design or technique that I can use to transmit the 48bit of data at 1.5MHz frequncy wirelessly. So, what I gathered so far is that a digital frequncy modulator can be made using a FPGA and the demodulator can also be made using FPGA. Am I right , if yes then i need more guidance , some literature to understand exaclty how can I do this? The thing that I do not still understand that If I am right about the FPGA based frequency modulator and domodulator then how would I design the wireless part of the system?

John

So, is it 1.6Mbps or 48x1.5=72Mbps?

The modulator/demodulator can be configurated/controlled by the FPGA, but you need analog RF circuits. You need to be very careful with PCB layouts. RF PCB layouts are very tricky.

First thing is to pick your encoding scheme. Manchester FM sounds good, as suggested by other posters.

Haven't you bothered to read any of the dozens of answers you've already gotten?

This is why people don't like googlies. Do you expect the answers to just show up on your desk or something? If you ask on USENET, you get answers on USENET.

Thanks, Rich

Send 48bits of data at 1.5Mhz is either:

or

a 1.5Mhz carrier frequency to send 48bits.

Which is it ??

As i come at this reading the whole thread OP is looking for about 1 mile range and three data sources.

Hi,

Each bit of the 48 bit data gets out of the FPGA at the rising edge of the 1.5MHz of the Clock. I found following two transciever chips

What do guys think? Has anybody worked with these chips before?

John