Abstract: Systems and methods for enhanced link adaptation are provided. In some embodiments, a method of operation of a network node includes calculating an actual RE efficiency based at least in part on an actual TBS obtained from a specification. The TBS may be obtained from a specification based on LA result and actual buffer data volume. The method also includes determining a real BLER from a searchable repository, based on the actual RE efficiency and an actual BLER. The method may further include calculating an actual outer-loop adjustment (OLA) step based on the actual BLER. The method may further include a dynamic outer-loop up/down step adjustment based on the actual OLA step.

Abstract: A method and system for performing link adaptation are disclosed. According to one aspect, a method in a wireless communication system for performing link adaptation is provided. The method includes, when a first measure of channel quality is higher than a first predetermined amount, using a first outer loop adjustment process directed to determining link adaptation for a first data transmission transmitted to a wireless device. The method also includes, when the first measure of channel quality is lower than a second predetermined amount, using a second outer loop adjustment process different from the first outer loop adjustment process directed to determining link adaptation for a second data transmission transmitted to the wireless device.

Abstract: There is provided a method performed by a wireless device for handling user data, wherein the user data are converted into codewords, each codeword having a first group of layers and a second group of layers. The method comprises: receiving an index from a network node, the index indicating a Transport Block Size (TBS) index, a Redundant Version (RV) and a differential modulation; determining a TBS based on the received index; determining a redundant version value based on the received index; determining a first modulation order for the first group and a second modulation order for the second group of a codeword, based on the differential modulation; and performing one of decoding and encoding the codeword based at least on the determined first and second modulation orders, the determined TBS and the determined redundant version value.

Abstract: A method, in a network in which a handover of a wireless device occurs, the User Equipment (UE) moving from a source cell to a target cell, is provided. The method comprises at least: (at the source cell) determining a sequence number (SN) related to a data packet; forwarding at the RLC layer data packets to the target cell, the data packets being previously sent to the UE but unacknowledged by the UE and having SNs inferior to the determined sequence number; and sending the determined SN to the target cell. The method further comprises (at the target cell) sending a first data packet with the determined SN to the wireless device; the determined SN being a demarcation line for using different encryption keys. The UE will decrypt the received data packets having SNs inferior to the determined SN using an encryption key from the source cell; and decrypt received packets having SNs superior to the determined SN using an encryption key from the target cell.

Abstract: According to one aspect of the disclosure, a network node for adjusting a maximum channel code rate limit of a wireless device is provided. The network node includes processing circuitry. The processing circuitry includes a processor and a memory. The memory contains instructions that, when executed by the processor, configure the processor to: cause transmission, to the wireless device, of at least one data transmission coded at a maximum channel code rate that is one of less than and equal to a maximum channel code rate limit, receive at least one indication of reception of the at least one data transmission coded at the maximum channel code rate by the wireless device, and in response to receiving the at least one indication of reception associated with the at least one data transmission coded at the maximum channel code rate, modify the maximum channel code rate limit.

Abstract: There is provided a method performed by a wireless device for handling user data, wherein the user data are converted into codewords, each codeword having a first group of layers and a second group of layers. The method comprises: receiving an index from a network node, the index indicating a Transport Block Size (TBS) index, a Redundant Version (RV) and a differential modulation; determining a TBS based on the received index; determining a redundant version value based on the received index; determining a first modulation order for the first group and a second modulation order for the second group of a codeword, based on the differential modulation; and performing one of decoding and encoding the codeword based at least on the determined first and second modulation orders, the determined TBS and the determined redundant version value.

Abstract: Systems and methods for enhanced link adaptation are provided. In some embodiments, a method of operation of a network node includes calculating an actual RE efficiency based at least in part on an actual TBS obtained from a specification. The TBS may be obtained from a specification based on LA result and actual buffer data volume. The method also includes determining a real BLER from a searchable repository, based on the actual RE efficiency and an actual BLER. The method may further include calculating an actual outer-loop adjustment (OLA) step based on the actual BLER. The method may further include a dynamic outer-loop up/down step adjustment based on the actual OLA step.

Abstract: According to one aspect of the disclosure, a network node for adjusting a maximum channel code rate limit of a wireless device is provided. The network node includes processing circuitry. The processing circuitry includes a processor and a memory. The memory contains instructions that, when executed by the processor, configure the processor to: cause transmission, to the wireless device, of at least one data transmission coded at a maximum channel code rate that is one of less than and equal to a maximum channel code rate limit, receive at least one indication of reception of the at least one data transmission coded at the maximum channel code rate by the wireless device, and in response to receiving the at least one indication of reception associated with the at least one data transmission coded at the maximum channel code rate, modify the maximum channel code rate limit.

Abstract: There is provided a method performed by a wireless device for handling user data. The method comprises: receiving an index (such as a Transport Block Size (TBS) index) from a network node; determining a TBS based on the received index; determining a modulation order based at least on the determined TBS; and performing one of decoding and encoding the user data based at least on the determined modulation order.

Abstract: A method and system for performing link adaptation are disclosed. According to one aspect, a method in a wireless communication system for performing link adaptation is provided. The method includes, when a first measure of channel quality is higher than a first predetermined amount, using a first outer loop adjustment process directed to determining link adaptation for a first data transmission transmitted to a wireless device. The method also includes, when the first measure of channel quality is lower than a second predetermined amount, using a second outer loop adjustment process different from the first outer loop adjustment process directed to determining link adaptation for a second data transmission transmitted to the wireless device.

Abstract: Systems and methods for Multiple-Input and Multiple-Output (MIMO) rank reduction to improve downlink throughput are disclosed. A method of operation of a radio access node includes determining that an imbalance between parallel channels of a spatial multiplexing downlink transmission to a wireless device is greater than an imbalance threshold and/or that a Negative Acknowledgement (NACK) rate over time for the parallel channels of a spatial multiplexing downlink transmission reported by the wireless device is greater than a NACK rate threshold. The method also includes, in response to determining that the imbalance between the parallel channels is greater than the imbalance threshold and/or that the NACK rate is greater than the NACK rate threshold, performing a fast rank reduction for a next downlink transmission whereby a rank is reduced from a rank indicator reported by the wireless device to some lower rank. Reducing the rank may improve downlink throughput.

Abstract: Systems and methods for control signal outer-loop adjustment are disclosed. In some embodiments, a method of operation of a network node in a cellular communications network is provided. The method includes transmitting a control signal and a data signal to a wireless device. The method also includes detecting an ambiguous state of reception of the control signal by the wireless device based on a feedback of reception of the data signal. The method also includes, in response to detecting the ambiguous state of reception, updating a link adaptation (LA) parameter used to choose a coding scheme and power level for transmission of information in the control signal. By updating the LA parameter in response to detecting the ambiguous state of reception, the network node may provide improved performance.

Abstract: In one embodiment, a method of operating a radio access node is provided. The method comprises determining whether support from a secondary cell is required for a wireless device to communicate with the radio access node, and, in response to determining that support from the secondary cell is required, calculating a modified channel condition outer-loop value for the secondary cell; and using the modified channel condition outer-loop value in an initial activation decision step for the secondary cell. The initial activation decision step may comprise activating the secondary cell in response to determining that the sum of a device reported channel condition value and the modified channel condition outer-loop value is above an activation threshold. Corresponding devices, computer programs and radio access nodes adapted to carry out the methods provided are also disclosed.

Abstract: Systems and methods for Multiple-Input and Multiple-Output (MIMO) rank reduction to improve downlink throughput are disclosed. A method of operation of a radio access node includes determining that an imbalance between parallel channels of a spatial multiplexing downlink transmission to a wireless device is greater than an imbalance threshold and/or that a Negative Acknowledgement (NACK) rate over time for the parallel channels of a spatial multiplexing downlink transmission reported by the wireless device is greater than a NACK rate threshold. The method also includes, in response to determining that the imbalance between the parallel channels is greater than the imbalance threshold and/or that the NACK rate is greater than the NACK rate threshold, performing a fast rank reduction for a next downlink transmission whereby a rank is reduced from a rank indicator reported by the wireless device to some lower rank. Reducing the rank may improve downlink throughput.

Abstract: In one embodiment, a method of operating a radio access node is provided. The method comprises determining whether support from a secondary cell is required for a wireless device to communicate with the radio access node, and, in response to determining that support from the secondary cell is required, calculating a modified channel condition outer-loop value for the secondary cell; and using the modified channel condition outer-loop value in an initial activation decision step for the secondary cell, The initial activation decision step may comprise activating the secondary cell in response to determining that the sum of a device reported channel condition value and the modified channel condition outer-loop value is above an activation threshold. Corresponding devices, computer programs and radio access nodes adapted to carry out the methods provided are also disclosed.

Abstract: Systems and methods for control signal outer-loop adjustment are disclosed. In some embodiments, a method of operation of a network node in a cellular communications network is provided. The method includes transmitting a control signal and a data signal to a wireless device. The method also includes detecting an ambiguous state of reception of the control signal by the wireless device based on a feedback of reception of the data signal. The method also includes, in response to detecting the ambiguous state of reception, updating a link adaptation (LA) parameter used to choose a coding scheme and power level for transmission of information in the control signal. By updating the LA parameter in response to detecting the ambiguous state of reception, the network node may provide improved performance.