Capture 1.6 GHz Bandwidth Spectrum Using Multiple Antennas

I want to fully utilize the 1.6 GHz bandwidth of the X410. What kind of computer hardware configuration should I use should I use (network card, cable, memory, storage, etc.)?

Answer 1

[Neil MacEwen]

Hi Chengrui,

As I assume you have already found, this example shows how to combine four channels on the X410 to gather 1.6GHz of bandwidth. Wireless Testbench supports connection to the X410 via a single 10GigE link connected to port QSFP28-0. To provide this connectivity you will need a QSFP28-to-4xSFP28 breakout cable (here is an example, but we cannot guarantee performance and there are many other alternatives) and a 10GigE network interface card for your host PC (here is an example, but we cannot guarantee performance and there are many other alternatives).

The example stores the captured data on the USRP itself (up to 4GB data) before bringing it to your host machine. You should ensure your machine has enough storage for multiple captures, should you wish to do so. The more computing power (RAM, CPU) your machine has, the better.

Thanks,

Neil

[chengrui]

Thank you for your response. I would like to know if the 10GigE rate is sufficient to fully utilize a 1.6G bandwidth, given that the sampling rate set in the routine is 500MSps.

[Neil MacEwen]

The example uses the basebandReceiver object which by default, and in this example, captures the data to the USRP itself before bringing the data to the host machine. This means that any high rate data is guaranteed to be captured without any dropped data on the USRP, then it can be brought back to the host for processing at a slower rate. It's a capture and post-process workflow rather than live streaming.

If you wish to see something more real-time, you would need to use the targeting workflow, although in that workflow the maximum sampling rate for the X410 is 250 Msps. See the Spectrum Visualization on NI USRP Radio example.

[chengrui]

So, how much data can the x410 store at once before transmitting to the host?

[Neil MacEwen]

Hi Chengrui,

It's documented here. The X410 can store 4 GB of data or 2^30 samples.

Thanks,

Neil

[chengrui]

Thank you for your patient and detailed answer.

[chengrui]

“I’d like to ask whether the USRP X410 can really capture 1.6 GHz of bandwidth simultaneously? My tests show that it can only reach up to 400 MHz bandwidth.

[Neil MacEwen]

The X410 can support 400 MHz of bandwidth per channel. The example combines four channels to generate the 1.6 GHz bandwidth. Whether that technique is suitable for you is dependent on your application.

[chengrui]

Can four channels be used to transmit a 1.6 GHz bandwidth signal?

[chengrui]

which version of FPGA image should I take to capture 1.6G BW signal. Now the version I use is X4_200

[Neil MacEwen]

"Can four channels be used to transmit a 1.6 GHz bandwidth signal?"

You can transmit four 400 MHz bandwidth signals simulataneously on four channels. What you transmit on those four channels is up to you. Here is the documentation for the basebandTransmitter.

"which version of FPGA image should I take to capture 1.6G BW signal. Now the version I use is X4_200"

FPGA image selection and loading is handled automatically by the tools. To use a sample rate of 500 Msps, the X1_200 bitstream will be loaded.

If you have further questions, please contact Support.