10 MHz bandwidth

[improperaffo]

Dear all,

my team and I are trying to transmit over a 10 MHz bandwidth. For that, we set srate: 11.52. When we run the code we get the following error:

/opt/srsRAN_Project/include/srsran/ran/phy_time_unit.h:105: constexpr srsran::phy_time_unit::value_type srsran::phy_time_unit::to_samples(U) const [with U = unsigned int; srsran::phy_time_unit::value_type = long int]: 
Assertion `is_sample_accurate(sampling_rate_Hz)' failed - Incompatible sampling rate 11.52 MHz with time 817408.

It seems that (std::abs(value) * sampling_rate_Hz) % (SCS_REF_HZ * N_F_REF * KAPPA)) in include/srsran/ran/phy_time_unit.h:89 is not zero. In fact we believe it to be 4789.5.

Similarly, when we want to run a 30 MHz bandwidth (using srate: 34.56), we get

/opt/srsRAN_Project/include/srsran/ran/phy_time_unit.h:105: constexpr srsran::phy_time_unit::value_type srsran::phy_time_unit::to_samples(U) const [with U = unsigned int; srsran::phy_time_unit::value_type = long int]: 
Assertion `is_sample_accurate(sampling_rate_Hz)' failed - Incompatible sampling rate 34.56 MHz with time 817408.

What else should we set in our configuration to fix this problem?
Thank you

[yagoda]

Hi, Can you share the config you using? Thanks, Justin

…

On Wed, 1 Nov 2023, 17:39 Raphael Cannatà, ***@***.***> wrote: Dear all, my team and I are trying to transmit over a 10 MHz bandwidth. For that, we set srate: 11.52. When we run the code we get the following error: /opt/srsRAN_Project/include/srsran/ran/phy_time_unit.h:105: constexpr srsran::phy_time_unit::value_type srsran::phy_time_unit::to_samples(U) const [with U = unsigned int; srsran::phy_time_unit::value_type = long int]: Assertion `is_sample_accurate(sampling_rate_Hz)' failed - Incompatible sampling rate 11.52 MHz with time 817408. It seems that (std::abs(value) * sampling_rate_Hz) % (SCS_REF_HZ * N_F_REF * KAPPA)) in include/srsran/ran/phy_time_unit.h:89 is not zero. In fact we believe it to be 4789.5. Similarly, when we want to run a 30 MHz bandwidth (using srate: 34.56), we get /opt/srsRAN_Project/include/srsran/ran/phy_time_unit.h:105: constexpr srsran::phy_time_unit::value_type srsran::phy_time_unit::to_samples(U) const [with U = unsigned int; srsran::phy_time_unit::value_type = long int]: Assertion `is_sample_accurate(sampling_rate_Hz)' failed - Incompatible sampling rate 34.56 MHz with time 817408. What else should we set in our configuration to fix this problem? Thank you — Reply to this email directly, view it on GitHub <#286>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AATLGFGDVVKH6TUH4W5GN53YCJ3MVAVCNFSM6AAAAAA6ZR44XOVHI2DSMVQWIX3LMV43ERDJONRXK43TNFXW4OZVHAYDEMZQHA> . You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>

[improperaffo]

gnb_id: 107

slicing:
 - sst: 1
   sd: 0
   
amf:
  addr: 10.43.206.196
  bind_addr: 10.16.0.182

ru_sdr:
  device_driver: uhd
  device_args:
  # clock:
  # sync:
  srate: 11.52
  otw_format: sc12
  tx_gain: 80
  rx_gain: 50

cell_cfg:
  dl_arfcn: 632628
  band: 78
  channel_bandwidth_MHz: 10
  common_scs: 30
  plmn: "00102"
  tac: 1
  pci: 1
  tdd_ul_dl_cfg:
    dl_ul_tx_period: 4
    nof_dl_slots: 2
    nof_dl_symbols: 7
    nof_ul_slots: 1
    nof_ul_symbols: 6
  nof_antennas_ul: 1
  nof_antennas_dl: 1
  pdsch:
    mcs_table: qam256
  pusch:
    mcs_table: qam256
  pucch:
    sr_period_ms: 4

e2:
  enable_du_e2: false
  e2sm_kpm_enabled: true
  addr: 10.43.183.80
  bind_addr: 10.16.0.182
  port: 36421

log:
  filename: /tmp/gnb.log
  all_level: info

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

[robertfalkenberg]

Hi,

I can confirm that TDD and srate: 11.52 cannot be set. However, you can use srate: 30.72 as a workaround.
(Note that some UE require at least 20MHz bandwidth in band n78 - check the UE Capability Information.)

Also for 30MHz bandwidth, you can use srate: 30.72.

[improperaffo]

Thank you, that was very helpful