Abstract: In mobile communications networks, requirements on signal distortion may be fulfilled at a lower bit rate, or alternatively quantization noise be reduced for a given bit rate, by including fractional exponent bits in a block floating point format. One or more fractional exponent bits may apply to all samples in the block. Alternatively, fractional bits may apply to sub-blocks within the block. The optimal number of fractional bits depends on the number of samples in the block.

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 by performed by a network node operating as a Distributed Unit (DU) includes configuring a plurality of Transmit/Receive Points (TRPs) in a group of TRPs to transmit a plurality of signals in a multiplexed sequence to at least one wireless device. Each TRP in the group of TRPS is associated with a shared cell. The network node receives, from the at least one wireless device, a response signal. Based on the response signal, the network node determines at least one TRP from the group of TRPs for use in transmitting at least one additional signal to the at least one wireless device.

Abstract: A method performed by an IRU of a base station system, the base station system comprising the IRU, a BBU connected to the IRU, and a first RH connected to the IRU via a packet data network. The first RH is arranged for wireless transmission in RF of a plurality of antenna carriers to UEs. The method comprises receiving, from the BBU, a plurality of first digital representations of the plurality of antenna carriers of the first RH, each first digital representation representing one antenna carrier, the plurality of first digital representations being received in a baseband frequency range, frequency multiplexing the plurality of first digital representations of the plurality of antenna carriers into a second digital representation over a first bandwidth, and transmitting the second digital representation to the first RH.

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: There is provided mechanisms for processing uplink signals. A method is performed by a RRU (200). The method comprises obtaining uplink signals (S102) as received from wireless devices at antenna elements of an antenna array of the RRU (200), each wireless device being associated with its own at least one user layer. The method comprises capturing (S104) energy per user layer by combining the received uplink signals from the antenna array for each user layer into combined signals, resulting in one combined signal per user layer. The combining for each individual user layer is based on channel coefficients of the wireless device associated with said each individual user layer. The method comprises providing (S106) the combined signals to a BBU (300).

Abstract: A method is disclosed performed by an RRU (120) of a distributed base station system (100) of a wireless communication network, the distributed base station system (100) further comprises a BBU (110) connected to the RRU, the RRU (120) being connected to a plurality of antennas (121, 122, 123) through which the RRU transmits user-layer signals to a plurality of UEs (161, 162, 163). The method comprises sending information related to received uplink signals to the BBU so that the BBU can obtain a first part of precoding coefficients to be used for precoding digital user-layer signals. The method further comprises obtaining a second part of the precoding coefficients and receiving, from the BBU, the digital user-layer signals precoded using the first part of the precoding coefficients.

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 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 distributed base station system comprises a remote radio unit, RRU, and a base band unit, BBU, connected to the RRU over a fronthaul link, the RRU being connected to N antennas. The method comprising by the RRU: obtaining uplink signals as received at the N antennas from a number of User Equipment, UEs, wirelessly connected to the RRU; obtaining a channel estimation matrix of the wireless communication channels; determining an interference covariance estimation matrix based on the obtained channel estimation matrix and on other channel information different from the channel estimation matrix; sending information on the channel estimation matrix and on the interference covariance estimation matrix to the BBU; determining intermediate signals based on the uplink signals, the channel estimation matrix and the interference covariance estimation matrix, and sending the intermediate signals to the BBU.

Abstract: Disclosed is a method performed by an IRU (210) of a base station system (200), the base station system comprising the IRU (210), a BBU (230) connected to the IRU (210), and a first RH (221) connected to the IRU (210) via a packet data network (240). The first RH (221) is arranged for wireless transmission in RF of a plurality of antenna carriers to UEs (250). The method comprises receiving, from the BBU (230), a plurality of first digital representations of the plurality of antenna carriers of the first RH (221), each first digital representation representing one antenna carrier, the plurality of first digital representations being received in a baseband frequency range, frequency multiplexing the plurality of first digital representations of the plurality of antenna carriers into a second digital representation over a first bandwidth, and transmitting the second digital representation to the first RH (221).

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 method performed by an encoder of a base station system, for handling a data stream for transmission over a transmission connection between a remote unit and a base unit of the base station system, the remote unit being arranged to transmit wireless signals to, and receive from, mobile stations. The method comprises quantizing a plurality of IQ samples, converting the quantized plurality of IQ samples to IQ predictions, calculating per sample a difference between the quantized plurality of IQ samples and the IQ predictions in order to create IQ prediction errors. The method further comprises quantizing the IQ predictions or the IQ prediction errors, entropy encoding the IQ prediction errors and sending the entropy encoded IQ prediction errors over the transmission connection to a decoder of the base station system. The method can be performed by a decoder.

Abstract: Disclosed is a method performed by a first unit, which is any of a baseband unit (170) and a radio unit (160) of abase station system (100). The method comprises transmitting a first user plane data stream to a second unit, which is the other of the baseband unit and the radio unit, over a first fronthaul link (165), using a first encoding scheme resulting in a first data rate, and transmitting a second user plane data stream to the second unit over a second fronthaul link (167), using a second encoding scheme resulting in a second data rate.

Abstract: Systems and methods for handling antenna signals are provided. In some embodiments, a method is performed by a first unit for handling antenna signals for transmission over a transmission connection with a second unit of the base station system. The base station system includes a base unit and a remote unit. The remote unit is arranged to transmit the antenna signals wirelessly to, and receive from, one or more wireless communication devices. The antenna signals each include a plurality of In-phase and Quadrature (IQ) samples. The first unit is the base unit and the second unit is the remote unit, or the first unit is the remote unit and the second unit is the base unit. In this way, quantization errors may typically add incoherently, i.e., adding quantization error power. Also, this may allow cancellation of quantization errors in certain directions depending on transformation type and transformation values.

Abstract: A method performed by a RRU of a distributed base station system, which further comprising a BBU, connected to the RRU. The RRU is arranged to wirelessly communicate with at least one UE. The method comprises determining a downlink channel estimate from received uplink signals and determining a first part of precoding coefficients to be used for precoding signals to be sent downlink to the at least one UE based on the determined downlink channel estimate. The method further comprises receiving a second part of the precoding coefficients from the BBU, precoding downlink signals of data received from the BBU using the first and the second part of the precoding coefficients and sending the precoded downlink signals to the at least one UE via the plurality of antennas.

Abstract: Described is a method performed by an encoder of a base station system of a wireless communication network, for handling a data stream comprising a number of consecutive IQ samples for transmission over a transmission network between a remote unit and a base unit of the base station system. The remote unit is arranged to transmit wireless signals to and receive from mobile stations, each of the number of IQ samples comprising a first number of bits.

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: In mobile communications networks, requirements on signal distortion may be fulfilled at a lower bit rate, or alternatively quantization noise be reduced for a given bit rate, by including fractional exponent bits in a block floating point format. One or more fractional exponent bits may apply to all samples in the block. Alternatively, fractional bits may apply to sub-blocks within the block. The optimal number of fractional bits depends on the number of samples in the block.

Abstract: Disclosed is a method performed by a first unit of a base station system of a wireless communication network for handling a signal for transmission over a fronthaul link between the first unit and a second unit of the base station system. The base station system includes a base unit and a remote unit. The method includes receiving the signal having at least one complex value, each consisting of two subparts, each being represented by a first number of bits, and transmitting the signal over the fronthaul link to the second unit, wherein at least two subparts are represented in a subgroup, the subgroup being a binary codeword having an integer number of bits that is a multiple of a second non-integer number of bits allocated per subpart, the second non-integer number of bits being fewer than the first number of bits.