Methods and Nodes for Detecting Activation of Serving Cell

A method, implemented by a network node of a wireless communication system supporting carrier aggregation, for detecting that an additional serving cell is activated, wherein the network node serves a wireless device configured with a first serving cell and the additional serving cell, the method comprising:

• configuring the wireless device to transmit feedback information associated with the additional serving cell at a first rate;
• transmitting a command to the wireless device to activate the additional serving cell;
• detecting the activation of the additional serving cell based on reception of feedback information from the wireless device;
• configuring the wireless device to transmit feedback information associated with the additional serving cell at a second rate after activation of the additional serving cell, wherein the second rate is lower than the first rate.

A method, implemented by a wireless device supporting carrier aggregation and configured with a first serving cell and an additional serving cell, for enabling detection of activation of the additional serving cell by a network node serving the wireless device, the method comprising:

• receiving a command from the network node to activate the additional serving cell;
• in response to the received command:
• adjusting a rate for transmitting feedback information associated with the additional serving cell to a first rate;
• and
• activating the additional serving cell;
• adjusting the rate for transmitting feedback information associated with the additional serving cell to a second rate, after activating the additional serving cell, wherein the second rate is lower than the first rate.

A network node of a wireless communication system, the network node for detecting that an additional serving cell is activated, the network node configured to support carrier aggregation and to serve a wireless device configured with a first serving cell and the additional serving cell, the network node comprising:

• a transceiver;
• a processing circuit operatively connected to the transceiver and configured to:
• configure the wireless device to transmit feedback information associated with the additional serving cell at a first rate;
• transmit, via the transceiver and to the wireless device, a command to activate the additional serving cell;
• detect the activation of the additional serving cell based on reception of feedback information from the wireless device;
• configure the wireless device to transmit feedback information associated with the additional serving cell at a second rate after activation of the additional serving cell, wherein the second rate is lower than the first rate.

A wireless device for enabling detection of activation of an additional serving cell by a network node of a wireless communication system supporting carrier aggregation, the network node serving the wireless device, the wireless device configured with a first serving cell and the additional serving cell, the wireless device comprising:

• a transceiver;
• processing circuit operatively connected to the transceiver and configured to:
• receive, via the transceiver and from the network node, a command to activate the additional serving cell;
• in response to the received command:
• adjust a rate for transmitting feedback information associated with the additional serving cell to a first rate;
• and
• activate the additional serving cell;
• adjust the rate for transmitting feedback information associated with the additional serving cell to a second rate, after activating the additional serving cell, wherein the second rate is lower than the first rate.