New release: MIMO 4x4 and improved performance

[ismagom]

Hi all,

Last week we pushed another release!

The main feature of this new release is 4-layer MIMO. To run it, you need a 4-channel SDR, such as the N310 or a 4-antenna RU. Then select 4 DL antennas in the config and you are ready to go.

In this picture we are running 50 MHz TDD 4x4 MIMO with a COTS Handset and the N310. Check out rank 4 NSG:

Besides this, we have also done improvements on CPU performance and the handling of some TDD patterns such as DDDXU. See this picture, where we are running 100 MHz TDD in 2x2 configuration and again the N310... more than 700Mbps!!

And finally, we continue to grow the number of O-RUs we support. This week we have added Picocom and Foxconn RU. As always, we provide example configs.

Enjoy it!

[mrouili]

Hi, I couldn't find the example configuration files for the N310 for these configurations in the configs folder, could you please provide them and are there any ones for the x310 ? Thank you

[peihaoY]

Thanks. That's where my system conflicts come in. So do you think it would be very difficult to modify srsue's code for MIMO by myself?

[pgawlowicz]

It is a very complex task.

[fahad-ece]

It is a very complex task.

Hi @pgawlowicz,

Hopefully you are doing well. If we use the default configuration files for 5G SA COTS UE setup then theoretically what will be the maximum throughput on the Downlink? Is there any straight-forward way to calculate that? Please let me know. Thank you.

[pgawlowicz]

I think around 70-80Mbps in DL, you can use one of the available 5G NR data rate calculators, for example:
https://5g-tools.com/5g-nr-throughput-calculator/

FDD, SISO, BW=20Hz, SCS=15kHz

[anasalbakri]

This is an example configuration to use the N310 in MIMO mode:

ru_sdr:
  device_driver: uhd                # The RF driver name.
  device_args: send_frame_size=8000,recv_frame_size=8000            # Optionally pass arguments to the selected RF driver.
  clock: external                      # Specify the clock source used by the RF.
  sync: external                       # Specify the sync source used by the RF.
  srate: 122.88                      # RF sample rate might need to be adjusted according to selected bandwidth.
  tx_gain: 55                       # Transmit gain of the RF might need to adjusted to the given situation.
  rx_gain: 40                       # Receive gain of the RF might need to adjusted to the given situation.
  expert_cfg: 
    low_phy_thread_profile: quad

cell_cfg:
  dl_arfcn: 650000                  # ARFCN of the downlink carrier (center frequency).
  band: 78                           # The NR band.
  channel_bandwidth_MHz: 100         # Bandwith in MHz. Number of PRBs will be automatically derived.
  common_scs: 30                    # Subcarrier spacing in kHz used for data.
  plmn: "00101"                     # PLMN broadcasted by the gNB.
  tac: 7                            # Tracking area code (needs to match the core configuration).
  pci: 1                            # Physical cell ID.
  pdsch: 
   mcs_table: qam256
   nof_ports: 2
  nof_antennas_dl: 2
  nof_antennas_ul: 1
  ssb: 
    ssb_block_power_dbm: 5

Hi @pgawlowicz @ismagom

This configuration doesn't work for me no matter whether I'm using Amarisot UE or not.
I wanna use it with Amarisoft UE over ZMQ.
But, It simply pops out the error:
--== srsRAN gNB (commit d5fa4f0) ==--

INI was not able to parse cell_cfg.pdsch.nof_ports

even when running help -h, nof-ports indeed is not a parameter under cell_cfg.pdsch
So, was this configuration based on a special test build or commit? or am I missing something?

[khooi8913]

Hi, is there any further detail on the specific Foxconn O-RU models that are currently supported? From the example configs, I can see that the RPQN4800E is supported, not sure about the RPQN780X series?

[brendan-mcauliffe]

Hi @khooi8913,

We have not tested other Foxconn O-RUs. That being said, assuming that the only difference is the supported frequency range, then yes. You will have to adjust the configuration file accordingly.

[khooi8913]

Hi @brendan-mcauliffe,

Thanks for clarifying. One follow-up question: can you also share the firmware version used for the RPQN4800E?
It would be helpful when engaging with the vendor. Thanks again!

[brendan-mcauliffe]

We are using Firmware v3.1.13q.551p1

[khooi8913]

Thanks a lot!

[omertylmzz]

Hi, does srsUE support 4-layer MIMO? Does it send the necessary CSI feedback to gNodeB? When I examined the srsUE codes, I saw that it calculates for 2 layers, am I missing something?

If srsUE does not perform these calculations, what exactly is the reason for this? (Computation complexity, etc.)

Thank you in advance for your feedback.

[pgawlowicz]

currently, we are not developing srsUE. It is unlikely that it will change in the near future. We use AmarisoftUE, which is a software implementation of a 5G UE.

[omertylmzz]

Hello Piotr,

Is there Multi-USRP support? Can we implement 4x4 MIMO structure with 2 USRP?

[pgawlowicz]

Hi, multi-USRP is not supported.

[omertylmzz]

Piotr, me again :(

Is there any obstacle to running srsRAN with phones that support n78? Can I run it after programming my SIM card?

There is no data given for S23 in the link below, but I don't see any reason why it wouldn't work.
"https://docs.srsran.com/projects/project/en/latest/knowledge_base/source/cots_ues/source/index.html#tested-cots-ues"

There is a tutorial in the link given below, but there is something that confuses me. Can we set the configurable SIMs we have with the "SysmoISIM-SJA2" program? Or did you use a special SIM card?

"https://docs.srsran.com/projects/project/en/latest/tutorials/source/cotsUE/source/index.html#overview"

If I can get it to work as given in the Tutorial I'll be happy to share the results with you for the S23.

[pgawlowicz]

In theory, it should work smoothly, but it's always essential to verify.

You should be able to use any programmable SIM with compatible programming software; the tutorial simply provides one example.

Piotr

[Moussa-Guemdani]

Hi all,

Last week we pushed another release!

The main feature of this new release is 4-layer MIMO. To run it, you need a 4-channel SDR, such as the N310 or a 4-antenna RU. Then select 4 DL antennas in the config and you are ready to go.

In this picture we are running 50 MHz TDD 4x4 MIMO with a COTS Handset and the N310. Check out rank 4 NSG:

Besides this, we have also done improvements on CPU performance and the handling of some TDD patterns such as DDDXU. See this picture, where we are running 100 MHz TDD in 2x2 configuration and again the N310... more than 700Mbps!!

And finally, we continue to grow the number of O-RUs we support. This week we have added Picocom and Foxconn RU. As always, we provide example configs.

Enjoy it!

Hello,
can we achieve this with usrp x310?

[omertylmzz]

I think you can most likely achive. We achieved using USRP X410. But your pc must be powerful enough.

[gabrielzb19]

Hi @osmanmerty I'm currently using an x410, but when deploying the gNB I have an error saying: Error: failed receiving packet. RfnocError: OpTimeout: Control operation timed out waiting for ACK.
Can you provide the most basic .yaml that worked for you please? Sorry for the inconveniences.

[omertylmzz]

Hi, sure.

cu_cp:
  amf:
    addr: 10.53.1.2                                             # The address or hostname of the AMF.
    port: 38412
    bind_addr: 10.53.1.1                                        # A local IP that the gNB binds to for traffic from the AMF.
    supported_tracking_areas:
      - tac: 7
        plmn_list:
          - plmn: "00101"
            tai_slice_support_list:
              - sst: 1

ru_sdr:
  device_driver: uhd
  device_args: addr=192.168.20.2,type=x4xx,num_recv_frames=64,num_send_frames=64
  sync: internal
  clock: internal
  srate: 122.88 # 30.72, 61.44, 122.88
  tx_gain: 50
  rx_gain: 50


cell_cfg:
  dl_arfcn: 650000
  band: 78
  channel_bandwidth_MHz: 100
  common_scs: 30
  plmn: "00101"
  tac: 7
  pci: 1
  nof_antennas_dl: 2
  nof_antennas_ul: 2
  pdsch:
    mcs_table: qam256
  ssb:
    ssb_period: 20

pcap:
  mac_enable: false
  mac_filename: /tmp/gnb_mac.pcap
  ngap_enable: false
  ngap_filename: /tmp/gnb_ngap.pcap

[gabrielzb19]

Hi again @osmanmerty
First of all, thank you very much for your response. I tried your .yaml file (obviosuly with the IP address of my x410) but the tiemout error still appears, I think I miss some hardware components in my setup like SFP cables or even an external reference (I'm currently setting reference as internal due to lack of material). I attach an image of my current setup, could you be kind of tell me which hardware I am missing if applicable, please? Sorry again for the inconveniences.