[srslte-users] What is the maximum channel delay (with channel emulator)?

[Bong Ho Kim]

Hi Justin,

Thank you so much.
It works with 333 usec one-way delay which is about 100km.

Brian

On Thu, Dec 3, 2020 at 3:49 AM Justin Tallon <
justin.tallon at softwareradiosystems.com> wrote:

> Hey bong,
>
> Just looked at your logs and conf there.
>
> If you want to do long-range capable RACHes you need to set the size of
> your cell to be larger.
>
> This is controlled by setting the zeroCorrelationZoneConfig in the
> sib.conf.
>
> The largest cell size setting is zeroCorrelationZoneConfig=0 which gives
> you a cell of 100km roughly.
>
> This way you can tolerate much later PRACH messages.
>
> Hope this helps!
> Justin
> ____
> Justin Tallon Ph.D.
>
> Software Radio Systems (SRS)
> http://www.softwareradiosystems.com
>
> +353-86-067-0753 | justin.tallon at softwareradiosystems.com
>
>
> On Thu, Dec 3, 2020 at 6:47 AM Bong Ho Kim <us.bhkim at gmail.com> wrote:
>
>> Hi Justin,
>>
>> I wonder if you had a chance to take a look at the long and have any
>> suggestions for me to resolve the issue on the RACH process with a long
>> channel delay.
>>
>> Thanks in advance,
>> Brian
>>
>>
>> On Wed, Nov 25, 2020 at 4:43 AM Bong Ho Kim <us.bhkim at gmail.com> wrote:
>>
>>> Hi Justin,
>>>
>>> Here is the log files with "log.all_level = info" for both eNB and UE.
>>>
>>>
>>> https://drive.google.com/file/d/1UiJkzQBLqbKcMemYvpSVkNHVzazNMVoX/view?usp=sharing
>>>
>>> Thank you very much for looking into this for me.
>>>
>>> Brian
>>>
>>>
>>> On Wed, Nov 25, 2020 at 3:26 AM Justin Tallon <
>>> justin.tallon at softwareradiosystems.com> wrote:
>>>
>>>> Hey Brian,
>>>>
>>>> Can you repeat this test with the log level set to "info" in both the
>>>> eNodeB and the UE?
>>>> log.all_level = info
>>>>
>>>> Regards,
>>>> Justin
>>>> ____
>>>> Justin Tallon Ph.D.
>>>>
>>>> Software Radio Systems (SRS)
>>>> http://www.softwareradiosystems.com
>>>>
>>>> +353-86-067-0753 | justin.tallon at softwareradiosystems.com
>>>>
>>>>
>>>> On Tue, Nov 24, 2020 at 6:29 PM Bong Ho Kim <us.bhkim at gmail.com> wrote:
>>>>
>>>>> Hi Justin,
>>>>>
>>>>> I am sorry that the file attachment seems not allowed.
>>>>> Here is the link to the log files.
>>>>>
>>>>>
>>>>> https://drive.google.com/file/d/1Vs7jBvOX2cqUdmMmfOv5fLnFa8vpSe-q/view?usp=sharing
>>>>>
>>>>> Thanks again,
>>>>> Brian
>>>>>
>>>>> On Tue, Nov 24, 2020 at 12:05 PM Bong Ho Kim <us.bhkim at gmail.com>
>>>>> wrote:
>>>>>
>>>>>> Hi Justin,
>>>>>>
>>>>>> Thanks for the quick response.
>>>>>> With your help, I have updated the enb.conf
>>>>>>      max_prach_offset_us  = 200
>>>>>>
>>>>>> both [channel.dl.delay] and  [channel.ul.delay] in the enb.conf file
>>>>>>      enable        = true
>>>>>>      period_s      = 3600
>>>>>>      init_time_s   = 0
>>>>>>      maximum_us    = 30
>>>>>>      minimum_us    = 30
>>>>>>
>>>>>> The RACH process failed again.
>>>>>> So I also tried the channel delay in the ue.conf (at the UE PC), but
>>>>>> the result is the same.
>>>>>> The ue.log indicates the following message, but in the sib.conf the
>>>>>> response window size is set to 10ms (ra_resp_win_size = 10;  // in ms)
>>>>>>       [MAC ] [E] [  394] RA response not received within the response
>>>>>> window
>>>>>>
>>>>>> The two PCs I have set up for (eNB+EPC) and (UE) are directly
>>>>>> connected using an ethernet cable.
>>>>>> I think not, but might the physical delay between two PCs have
>>>>>> affected it?
>>>>>>
>>>>>> To have more of your help I have attached (log.tar.gz) the log, pcap,
>>>>>> and config files at the UE and ENB sides.
>>>>>>
>>>>>> Thank you,
>>>>>> Brian
>>>>>>
>>>>>>
>>>>>>
>>>>>> On Tue, Nov 24, 2020 at 5:05 AM Justin Tallon <
>>>>>> justin.tallon at softwareradiosystems.com> wrote:
>>>>>>
>>>>>>> Hey,
>>>>>>>
>>>>>>> You need to increase max_prach_offset_us in the enodeb conf.
>>>>>>>
>>>>>>> Regards,
>>>>>>> Justin
>>>>>>> ____
>>>>>>> Justin Tallon Ph.D.
>>>>>>>
>>>>>>> Software Radio Systems (SRS)
>>>>>>> http://www.softwareradiosystems.com
>>>>>>>
>>>>>>> +353-86-067-0753 | justin.tallon at softwareradiosystems.com
>>>>>>>
>>>>>>>
>>>>>>> On Tue, Nov 24, 2020 at 10:27 AM Bong Ho Kim <us.bhkim at gmail.com>
>>>>>>> wrote:
>>>>>>>
>>>>>>>> Dear srsLTE team,
>>>>>>>>
>>>>>>>> I have installed srsLTE Release 20.04.2, and the UE is attached to
>>>>>>>> the srsLTE and can ping to the network when the channel emulator is
>>>>>>>> disabled or channel delay is very small (i.e. 10 usec)
>>>>>>>>
>>>>>>>> But, I am trying to use about 100 usec delay for DL and 100 msec
>>>>>>>> delay for UL using the "channel delay" configuration at eNB.
>>>>>>>> So I updated the eNB side config file like below.
>>>>>>>>
>>>>>>>> *[channel.dl.delay]*
>>>>>>>> enable = true
>>>>>>>> period_s = 3600
>>>>>>>> init_time_s = 0
>>>>>>>> maximum_us = 100
>>>>>>>> minimum_us = 100
>>>>>>>>
>>>>>>>> *[channel.ul.delay]*
>>>>>>>> enable = true
>>>>>>>> period_s = 3600
>>>>>>>> init_time_s = 0
>>>>>>>> maximum_us = 100
>>>>>>>> minimum_us = 100
>>>>>>>>
>>>>>>>> Once channel delay is added ( RTT= 200 usec), the RACH process has
>>>>>>>> failed.
>>>>>>>> I believe that a 200 usec delay should be handled through the
>>>>>>>> Timing Advance bits (11-bit) in the RAR message.
>>>>>>>>
>>>>>>>> Would you let me know the maximum channel delay that can be used in
>>>>>>>> the srsLTE configuration if it was different from the standard?
>>>>>>>>
>>>>>>>> Thank you in advance,
>>>>>>>>
>>>>>>>> Brian
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> _______________________________________________
>>>>>>>> srslte-users mailing list
>>>>>>>> srslte-users at lists.softwareradiosystems.com
>>>>>>>> http://www.softwareradiosystems.com/mailman/listinfo/srslte-users
>>>>>>>>
>>>>>>>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.srsran.com/pipermail/srsran-users/attachments/20201203/13bfc940/attachment.htm>