Menetelmä ja järjestely kellosignaalin säätämiseksi

摘要

An arrangement for adjusting a clock signal (115) in a network element (101) of a communications network comprises a processor device (111 to 114) arranged to produce a control variable (116) containing information about synchronisation messages (106 to 109) received from at least two other network elements (102 to 105). A situation in which the reception from a sending network element of synchronisation messages of a good enough quality ceases will not significantly disturb the clock signal to be adjusted because only a part of the control variable used for the adjustment depends on synchronisation messages sent by an individual network element. In an arrangement according to an advantageous embodiment the reference value of the control variable is changed in response to a situation where the reception from a sending network element of synchronisation messages of a good enough quality ceases. Thus it is possible to reduce the change of the difference between the control variable and its reference value which further reduces disturbances caused in the clock signal to be adjusted.