Methods and Nodes Relating to System Information Acquisition During Flexible Subframe Operation

A method performed in a wireless device located in a first cell operated by a network node of a wireless communication system, the method comprising:

• acquiring system information of a second cell using at least one autonomous gap during a time period, wherein the wireless device is configured with a flexible subframe allocation scheme in the first cell during at least a part of the time period;
• obtaining a value Nmin corresponding to a minimum number of uplink feedback signals, where the value Nmin is associated with the flexible subframe allocation scheme;
• and
• transmitting at least the minimum number Nmin of uplink feedback signals in response to downlink data during the time period.

A method performed in a network node of a wireless communication system operating a first cell, wherein a wireless device is served by the first cell, the method comprising:

• transmitting configuration information to the wireless device, configuring the wireless device to operate with a flexible subframe allocation scheme in the first cell during at least part of a time period during which the wireless device acquires system information of a second cell;
• obtaining a value Nmin associated with the flexible subframe allocation scheme, the value Nmin corresponding to a minimum number of uplink feedback signals that the wireless device shall transmit in response to downlink data during the time period;
• transmitting downlink data to the wireless device in the first cell during the time period;
• and
• receiving at least the minimum number Nmin of uplink feedback signals in the first cell in response to the transmitted downlink data.

A wireless device configured to, when located in a first cell operated by a network node of a wireless communication system:

• acquire system information of a second cell using at least one autonomous gap during a time period, wherein the wireless device is configured with a flexible subframe allocation scheme in the first cell during at least a part of the time period;
• obtain a value Nmin corresponding to a minimum number of uplink feedback signals, where the value Nmin is associated with the flexible subframe allocation scheme;
• and
• transmit at least the minimum number Nmin of uplink feedback signals in response to downlink data during the time period.

A network node for a wireless communication system configured to operate a first cell, wherein a wireless device is served by the first cell, the network node being configured to:

• transmit configuration information to the wireless device, configuring the wireless device to operate with a flexible subframe allocation scheme in the first cell during at least part of a time period during which the wireless device acquires system information of a second cell;
• obtain a value Nmin associated with the flexible subframe allocation scheme, the value Nmin corresponding to a minimum number of uplink feedback signals that the wireless device shall transmit in response to downlink data during the time period;
• transmit downlink data to the wireless device in the first cell during the time period;
• and
• receive at least the minimum number Nmin of uplink feedback signals in the first cell in response to the transmitted downlink data.

A non-transitory computer readable medium storing a computer program comprising computer readable code that, when executed on a processing circuit of a wireless device located in a first cell operated by a network node of a wireless communication system, causes the processing circuit to:

• acquire system information of a second cell using at least one autonomous gap during a time period, wherein the wireless device is configured to use a flexible subframe allocation scheme in the first cell during at least a part of the time period;
• obtain a value Nmin corresponding to a minimum number of uplink feedback signals, where the value Nmin is associated with the flexible subframe allocation scheme;
• and
• transmit at least the minimum number Nmin of uplink feedback signals in response to downlink data during the time period.

A non-transitory computer readable medium storing a computer program comprising computer readable code that, when executed on a processing circuit of a network node of a wireless communication system configured to operate a first cell that serves a wireless device, causes the processing circuit to:

• transmit configuration information to the wireless device, configuring the wireless device to use a flexible subframe allocation scheme in the first cell during at least part of a time period during which the wireless device acquires system information of a second cell;
• obtain a value Nmin associated with the flexible subframe allocation scheme, the value Nmin corresponding to a minimum number of uplink feedback signals that the wireless device shall transmit in response to downlink data during the time period;
• transmit downlink data to the wireless device in the first cell during the time period;
• and
• receive at least the minimum number Nmin of uplink feedback signals in the first cell in response to the transmitted downlink data.