Generic selectors
Exact matches only
Search in title
Search in content
Post Type Selectors

Power Control Message to MS by BSC

  • This topic has 9 replies, 1 voice, and was last updated 12 years ago by Thiagu.
Viewing 10 posts - 1 through 10 (of 10 total)
  • Author
    Posts
  • #64882
    Junior RF Man
    Guest

    Hi Guys,

    If BSC makes decision for performing Power Control on uplink (MS PC) and it should send some message through Um interface to MS for starting power control.

    What is the name of this message? Is it coming on the System Information messages, if yes on which
    SI message is it?

    #64883
    Pix
    Guest

    Hello,

    There is no message to signal the start of PC.
    It is all up to the BSC, the MS doesn’t have to know anything.
    As soon as PC is enabled, the BSC will start sending power control orders to MS and BTS.
    The power control orders is not really an order : it is just that instead of telling the MS to transmit at 33dBm (for ex.) it will say “30dB” or “28dB”, etc.
    By default, with PC disabled, the BSC always transmit the value 33dBm.
    To the BTS, for the DL PC, it says “0dB”, which means the BTS should attenuate its tx power by 0dB.

    I hope i was clear… hum…

    regards
    pix

    #64884
    Junior RF Man
    Guest

    It means, in the layer 3 messages we can see MS_TX_PWR_MAX (33, 30, 28…) during the power control. Yes or not?

    #64885
    fede
    Guest

    hi guys
    there is also the pwrc bit (power control indicator) within Cell Options (SI3)

    #64886
    fede
    Guest

    @junior
    the ordered PC level from BSS is in the L1 header

    #64887
    pix
    Guest

    yes, it’s in layer 1.

    the pwrc refers to the measurement process rather than the power control process (check 3GPP TS 45.008, look for pwrc)

    regards
    pix

    #64888
    fede
    Guest

    hi pix, thanks a lot!
    I did misunderstand the meaning of pwrc bit.

    #64889
    Junior RF Man
    Guest

    So I can not see MS PC Adjustment on TEMS Investigation. Right?

    #64890
    SHELDON
    Guest

    Hi,

    On the downlink SACCH, the BTS sends the MS a power order, which informs the MS as to which power to transmit on. When MS power control is activated in the cell, the power order can ‘instruct’ the MS to transmit on a lower or higher power.

    In TEMs, you can’t see the SACCH message, but you can see the current ‘MS Power Control Level’ the GSM Radio Parameters window. The values given there are in multiples of 2, so eg, if the power control level is 3, the MS should transmit 6dB below the maximum power.

    Regards,
    SHELDON

    #64891
    Thiagu
    Guest

    Is that Means with PC Disabled MS will Transmit at Max Power?

Viewing 10 posts - 1 through 10 (of 10 total)
  • The forum ‘Telecom Design’ is closed to new topics and replies.