Communication tester settings for maximum throughput

[felixbjork]

Hi!

We are using the nRF9160 in a product. The product brief specifies a max throughput of 300/375 kbps (UL/DL) for LTE Cat-M1 and 30/60 kbps (UL/DL) for NB-IoT. Can you tell me what settings to use to achieve this throughput? Number of RBs, MCS index etc. 

Thank you!

BR,
Felix 

[Didrik Rokhaug]

The throughput numbers in the product brief are for the pyhisical layer, so the throughput seen by the application will be a bit lower.

However, it is possible to come where close to the theoretical limits. Note that in NCS v1.5.0 and 1.5.1, you might have to increase the buffer sizes used by the nrf_modem library to acheive maxmimum throughput.

When it comes to how to configure the physical layer, the speed can be achieved by selecting max the PRB and MSC (e.g.LTE-M PRB= 6 and MCS=15).

[felixbjork]

Hi!

We seem to have some issues with achieving the advertised max throughput. We are using an Anritsu MT8821C to measure the throughput. The highest throughput we can achieve is 211/70 kbps (UL/DL) by setting the communication tester to 6 RBs, MCS index 9 on UL and MCS index 10 on DL. If we set the MCS index any higher, the throughput measurement cannot be performed anymore. Do you have any configuration file for the MT8821C that you can share to achieve higher throughput?

BR,
Felix

[Didrik Rokhaug]

Hi,

Are those numbers the peak or average rate?

The numbers in the product brief is the maximum peak rate, not average data rate.

It might also depend on the tester/eNB if those numbers can be achieved.

Best regards,

Didrik