Abstract: A method is provided for evaluating a first time-domain signal received from a single source, wherein the time domain signal is processed with a Fourier-related transform with overlapping input frames to provide a first frequency-domain signal being made up of frames of coefficients, wherein only one part is included in the first frequency-domain signal, wherein a first part is the part, real or imaginary, that is included in the frequency-domain signal and a second part is the part, real or imaginary, that is not included in the frequency-domain signal. The method is performed by a signal evaluator. The method comprises: receiving the first frequency-domain signal; obtaining a reference frequency-domain signal; and determining a first cross-correlation between the received first frequency-domain signal and the reference frequency-domain signal by cross-correlating the received first frequency-domain signal and the reference frequency-domain signal.

Abstract: A network entity can be in a communications network that includes a plurality of network nodes communicatively coupled to the network entity via a cascaded topology. The network entity can transmit scheduling information to a first network node of the plurality of network nodes. The network entity can further receive an indication of an intermediate beamforming weight from the first network node. The network entity can further determine a part of a frequency-domain beamforming weight based on the indication of the intermediate beamforming weight. The network entity can further transmit an indication of the part of the frequency-domain beamforming weight to the first network node. The network entity can further communicate data with the communication device via the first network node.

Abstract: A method and transition device for enabling communication of data between a remote radio unit and a central baseband unit in a wireless network. When detecting a first interface configuration used by the remote radio unit and a second interface configuration used by the baseband unit, the transition device configures interface functions, based on the first and second interface configurations. The interface functions are selected from a set of predefined interface functions associated with different interface configurations. The transition device then establishes a data flow between the remote radio unit and the central baseband unit over the transition device, and performs conversion between the first interface configuration and the second interface configuration for data communicated in the data flow, using the selected interface functions.

Abstract: A first network node (360, 2300) can be a part of a communications network that includes a second network node communicatively coupled to the first network node via a fronthaul interface and that includes a communication device communicatively coupled to the first network node. The first network node can generate (830) first data associated with an uplink signal received from the communication device. The first network node can further generate (840) second data associated with the uplink signal received from the communication device. The first network node can prioritize (850, 860) transmission of the first data to the second network node via the fronthaul interface over transmission of the second data to the second network node via the fronthaul interface.

Abstract: A method performed by a distributed base station system of a wireless communication network. The distributed base station system comprises a base band unit (BBU) and a remote radio unit (RRU) connected to each other over a fronthaul link. The method comprises receiving uplink signals at N antennas of the RRU from a number of user equipment (UEs) connected to the RRU. The BBU determines first beamforming weights based on a first reference signal that is has received from the UEs and sends the first beamforming weights to the RRU. The RRU then determines intermediate signals from the first beamforming weights and the uplink signals and sends the intermediate signals to the BBU. The BBU then determines second beamforming weights from a second reference signal it has received from the RRU. Then, the BBU determines an output signal based on the intermediate signal and the second beamforming weights.

Abstract: Disclosed is a method performed by a first radio unit, RU, of a distributed base station system. The distributed base station system further comprises a Baseband Unit, BBU, connected to the first RU over a fronthaul link and a second RU connected to the first RU over an RU link. The first RU determines first part of beamforming weights that it uses for performing a first part of the beamforming of uplink signals received at its antennas into intermediate signals. The first RU further determines intermediate beamforming weights to be used for a second part of beamforming at the BBU. The first RU further receives, from the second RU, intermediate signals and intermediate beamforming weights determined by the second RU. The first RU combines the intermediate signals and sends them to the BBU. The first RU further combines the intermediate beamforming weights and sends them to the BBU.

Abstract: A first network node, a second network node and methods therein, for handling baseband processing of signals communicated with wireless devices in a wireless network. The first network node communicates a first type of signals with a first wireless device and performs a first part of baseband processing of the first type of signals using a non-GPP implemented processor. The first network node also communicates the first type of signals with the second network node for a second part of baseband processing of the first type of signals using a GPP implemented processor. The first network node further communicates a second type of signals with a second wireless device and performs both of said first and second parts of baseband processing of the second type of signals using the non-GPP implemented processor.

Abstract: A method and transition device for enabling communication of data between a remote radio unit and a central baseband unit in a wireless network. When detecting a first interface configuration used by the remote radio unit and a second interface configuration used by the baseband unit, the transition device configures interface functions, based on the first and second interface configurations. The interface functions are selected from a set of predefined interface functions associated with different interface configurations. The transition device then establishes a data flow between the remote radio unit and the central baseband unit over the transition device, and performs conversion between the first interface configuration and the second interface configuration for data communicated in the data flow, using the selected interface functions.

Abstract: Disclosed is a method performed by a first radio unit, RU, (140) of a distributed base station system (100), the first RU (140) comprising Ni antennas (141, 142), the distributed base station system (100) further comprising a first aggregation unit, AU, (120) connected to the first RU (140) via a first AU fronthaul, FH, link (145) and a second RU (150) connected to the first AU (120) via a second AU FH link (155), the second RU (150) comprising N2 antennas (151, 152), the distributed base station system (100) further comprising a BBU (110) connected to the first AU (120) over a first BBU FH link (115). The method comprises receiving, from a first number of UEs (181, 182, 183), uplink, UL, data streams comprising first user layers of the first number of UEs (181, 182, 183).

Abstract: Disclosed is a method performed by a first radio unit, RU, (140) of a distributed base station system (100), the first RU (140) comprising Ni antennas (141, 142), the distributed base station system (100) further comprising a first aggregation unit, AU, (120) connected to the first RU (140) via a first AU fronthaul, FH, link (145) and a second RU (150) connected to the first AU (120) via a second AU FH link (155), the second RU (150) comprising N2 antennas (151, 152), the distributed base station system (100) further comprising a BBU (110) connected to the first AU (120) over a first BBU FH link (115). The method comprises obtaining a first downlink, DL, channel estimate of a communication channel between the first RU (140) and a first number of UEs (181, 182, 183), determining first intermediate beamforming weights, BFW, and sending, to the first AU (120), the determined first intermediate BFW.

Abstract: A method by a RU node for performing frequency-domain beamforming for communication between a base station (BS) and UEs in a network using a multiple antenna system, the BS including a DU node connected to the RU node, the method including: obtaining uplink signals including K user-layer signals overlaid with interference signals and noise as received at N antennas from a number of UEs; determining: a channel estimation matrix H of wireless communication channels between a number of UEs and N antennas; an estimate of an Interference plus Noise covariance matrix Q based on H and other channel information; a first part beamforming weights, BFWs; an effective channel matrix Heff based on H and the first part BFWs; and intermediate uplink signals having K components and based on the uplink signals and the first part BFWs; and sending Heff and the intermediate uplink signals towards the DU node.

Abstract: Disclosed is a method performed by a BBU system of a wireless communication network, comprising a distributed base station system (100), which comprises a BBU (110) and an RRU (120) connected over a fronthaul link (140). The method comprises determining first and second parts of beamforming weights based on a determined downlink channel estimate, and compressing the second part of the beamforming weights. The first part of the beamforming weights is determined for performing interference cancellation between user-layer signals, and the second part is determined for expanding the user-layer signals to antenna signals. The BBU then sends the first part and the compressed second part of the beamforming weights to the RRU, as well as the user-layer signals, over the fronthaul link (140). The RRU (120) then beamforms the user-layer signals according to the first and the second parts of the beamforming weights before sending the signals to a number of UEs (131, 132, 133).

Abstract: A first network entity of a communications network can generate compressed beamforming weights (“BFWs”) based on a transformation configuration. The transformation configuration can be based on one or more parameters of an antenna array associated with a second network entity of the communications network. The one or more parameters can include a parameter that is separate from a total number of antenna ports in the antenna array. The first network entity can further transmit an indication of the compressed BFWs to the second network entity via a fronthaul between the first network entity and the second network entity.

Abstract: A method performed by a distributed base station system of a wireless communication network. The distributed base station system comprises a base band unit (BBU) and a remote radio unit (RRU) connected to each other over a fronthaul link. The method comprises receiving uplink signals at N antennas of the RRU from a number of user equipment (UEs) connected to the RRU. The BBU determines first beamforming weights based on a first reference signal that is has received from the UEs and sends the first beamforming weights to the RRU. The RRU then determines intermediate signals from the first beamforming weights and the uplink signals and sends the intermediate signals to the BBU. The BBU then determines second beamforming weights from a second reference signal it has received from the RRU. Then, the BBU determines an output signal based on the intermediate signal and the second beamforming weights.

Abstract: A network entity can be in a communications network that includes a plurality of network nodes communicatively coupled to the network entity via a cascaded topology. The network entity can transmit scheduling information to a first network node of the plurality of network nodes. The scheduling information can indicate user layers to be used for communication with a communication device. The network entity can further receive an indication of an intermediate beamforming weight from the first network node. The network entity can further determine a part of a frequency-domain beamforming weight based on the indication of the intermediate beamforming weight. The network entity can further communicate with the communication device via the first network node using the part of the frequency-domain beamforming weight.

Abstract: A method for determining a relation between a first time-domain signal and a second time-domain signal received from a single source is provided. The time domain signals are respectively processed with a Fourier-related transform to indirectly or directly provide respective first and second frequency-domain signals being made up of frames. Only one part from the Fourier-related transform is included. A first part is the part that is included and a second part is the other part. The method comprises the steps of: receiving the frequency-domain signals; determining a first part cross-correlation by cross-correlating corresponding frames in the first frequency-domain signal and the second frequency-domain signal, for the first part; and determining a second part cross-correlation by cross-correlating non-corresponding frames in the first frequency-domain signal and the second frequency-domain signal, for the second part.

Abstract: Disclosed is a method performed by a RRU of a distributed base station system of a wireless communication network, the RRU being connected to a BBU over a fronthaul link, the RRU being connected to N antennas. The method comprises obtaining uplink signals as received at the antennas from UEs wirelessly connected to the RRU, and obtaining a channel estimation matrix of wireless communication channels between UEs and the antennas. The method further comprises determining an error estimation matrix based on the channel estimation matrix, and on received reference signals yref,l, the received reference signals having L symbols, L being smaller than N, determining intermediate signals, based on the uplink signals, the channel estimation matrix and the error estimation matrix, and sending to the BBU over the fronthaul link, the determined intermediate signals.

Abstract: A method (1700) for antenna power scaling in a fronthaul lower-layer split, LLS, is provided. The method is performed by a baseband unit, BBU (102, 202, 302), for assisting a Radio Unit, RU (104, 204, 304), in scaling a transmit power of one or more antennas when performing beamforming. The method includes transmitting (1702) at least one antenna power scaling factor to the RU for scaling the transmit power of the one or more antennas.

Abstract: A method is provided, performed by a Baseband Unit (BBU) for assisting a Radio Unit (RU) to perform beamforming for a communication between a User Equipment (UE) and a base station in a wireless communications network using a multiple antenna system for communication. The BBU and the RU are associated with the base station. The BBU calculates (401) respective Beamforming Weights. BFWs, for at least a subset of subcarriers out of a number of subcarriers. The BBU transforms (402) by a mathematical transformation, the respective calculated BFWs, from frequency domain BFWs to obtain tap-domain BFWs. The BBU select (403) one or more tap-domain BFWs from said obtained tap-domain BFWs. The BBU sends (404) to the RU, the selected one or more the tap-domain BFWs. The selected one or more tap-domain BFWs assists the RU to perform beamforming for the communication between the CE and the base station.

Abstract: Disclosed is a method performed by a first radio unit, RU, of a distributed base station system. The distributed base station system further comprises a Baseband Unit, BBU, connected to the first RU over a fronthaul link and a second RU connected to the first RU over an RU link. The first RU determines first part of beamforming weights that it uses for performing a first part of the beamforming of uplink signals received at its antennas into intermediate signals. The first RU further determines intermediate beamforming weights to be used for a second part of beamforming at the BBU. The first RU further receives, from the second RU, intermediate signals and intermediate beamforming weights determined by the second RU. The first RU combines the intermediate signals and sends them to the BBU. The first RU further combines the intermediate beamforming weights and sends them to the BBU.