Abstract: There is provided mechanisms for determining a precoder for APs in a cell-free communication system. A method is performed by a controller of the APs. The method comprises obtaining channel estimates of a radio propagation channel between the APs and user equipment served in the cell-free communication system. The method comprises determining a precoder for the APs. The precoder has a ZF precoding factor and a power allocation factor. The ZF precoding factor is determined from the channel estimates. The power allocation factor is determined by maximizing total transmission power for all user symbols to be transmitted to the user equipment, one user symbol per each user equipment. Transmission power of each of the APs is not larger than a power constraint. Transmission power for each of the user equipment is lower bounded by a scaled heuristic value. The method comprises initiating transmission of precoded user symbols from the APs towards the user equipment.

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 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: 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: 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: Described is a method performed by an encoder of a base station system (100) of a wireless communication network, for handling a bit stream for transmission over a transmission link (165) between a remote unit (160) and a base unit (170) of the base station system. The remote unit is arranged to transmit wireless signals to and receive from mobile stations (180). The bit stream comprises a first OFDM symbol and a second OFDM symbol, each OFDM symbol comprising a number of consecutive IQ samples. The method comprises, for a first number of the IQ samples situated at a boundary between the first and the second OFDM symbol, transmitting, over the transmission link to a decoder of the base station system, the first number of IQ samples having a representation spanning a first amplitude range.

Abstract: Described is a method performed by an encoder of a base station system (100) of a wireless communication network, for handling a bit stream for transmission over a transmission link (165) between a remote unit (160) and a base unit (170) of the base station system. The remote unit is arranged to transmit wireless signals to and receive from mobile stations (180). The bit stream comprises a first OFDM symbol and a second OFDM symbol, each OFDM symbol comprising a number of consecutive IQ samples. The method comprises, for a first number of the IQ samples situated at a boundary between the first and the second OFDM symbol, transmitting, over the transmission link to a decoder of the base station system, the first number of IQ samples having a representation spanning a first amplitude range.

Abstract: Disclosed is a method performed by an IRU (210) of abase 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: 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.