Abstract: The present disclosure relates to radio network communication. In one of its aspects, the present disclosure relates to a method, performed by a first APU, for sequential transmit precoding in a radio stripe system. The system comprises at least two APUs connected 5 in series from a CPU and serves at least two UEs. According to the method, channel estimates for channels to the served UEs are obtained and based on these, a precoding filter is determined. The precoding filter is going to be applied to signals that are to be transmitted from the first APU to the UEs. Thereafter, based on the determined precoding filter and the obtained channel estimates, effective precoded channels for the 0 signals to the UEs are determined. These represent the effective channel created after the precoding filter being applied to each channel for the UEs. The effective precoded channels are transmitted to at least one subsequent second APU.

Abstract: The present disclosure relates to radio network communication. In one of its aspects, the present disclosure relates to a method, performed by a first APU, for sequential receive combining in a radio stripe system. The system comprises at least two APUs connected in series to a CPU and serves at least two UEs. According to the method, channel estimates for channels to said served UEs are received and based on these, a receive combining filter is determined. The receive combining filter is to be applied to received data signals. Thereafter, based on the obtained channel estimates and the determined receive combining filter, effective channels from said served UEs are determined. These represent the effective channel created after the receive combining filter being applied to each channel for said served UEs. The effective channels are transmitted from said served UEs to at least one subsequent second APU.

Abstract: The embodiments herein relate to a method performed by an APU (103) for handling data transmissions in a distributed massive MIMO communication system (100). The APU (103) is comprised in one of at least two non-co-located groups of APUs (103) in the system (100). The APU (103) determines a first pre-coding configuration and a DL reference signal. The APU (103) transmits, to a UE (125), the DL reference signal pre-coded with the first pre-coding configuration. The APU (103) receives information indicating at least one phase adjustment parameter from the UE (125), and determines a second pre-coding configuration based on the first pre-coding configuration adjusted with the phase adjustment parameter. The APU (103) transmits DL data pre-coded with the second pre-coding configuration to the UE (125).

Abstract: An antenna system includes at least a first antenna processing unit, APU1, and a second antenna processing unit, APU2, adjacently connected to each other through a serialized front haul. Each one of the APU1 and APU2 has at least two antenna elements. The antenna elements of APU1 are connected to their respective Radio Frequency, RF, chains via a first beamforming unit, and the antenna elements of APU2 are connected to their respective RF chains via a second beamforming unit. A network node configures the first beamforming unit and the second beamforming unit such that an absolute value of an angular difference between at least one of the beam directions generated by the first beamforming unit and each of the beam directions generated by the second beamforming unit exceeds or is equal to a threshold value.

Abstract: A method of operating a distributed MIMO system is disclosed. The distributed MIMO system is configured to serve a plurality of wireless communication devices (u1, . . . , uN). The distributed MIMO system comprises a number of access points (A1, . . . , AK), each comprising a time circuit (180) configured to keep track of a local time of the access point (A1, . . . , AK). The method comprises performing (210) an intra-group synchronization procedure for a group (G1) of at least three access points (A1-A3). The intra-group synchronization procedure comprises, for each access point (Ai) in the group (G1), transmitting (Ti), from that access point (Ai), a synchronization signal and obtaining (Oi) a transmission time indicator indicating a transmission time of that synchronization signal in the local time of that access point (Ai).

Abstract: A method of a receiver is used for receiving an amplitude shift keyed signal provided over a multi-layered transmission from a plurality of antennas with different precoding of different symbols for the respective layers. The method comprises receiving a sequence of signal values of the signal, estimating, from the sequence of signal values, channels for the respective layers, and selecting one of a plurality of detection methods based on a difference in quality between the estimated channels A receiver and a computer program are also disclosed.

Abstract: A method, in a base station, for transmitting first control channel information to a first wireless device and second control channel information to a second wireless device in a wireless communications network. The method comprises obtaining an indication of whether a spatial relationship between the first wireless device and the second wireless device meets a predetermined condition and operating in one of a first mode and a second mode based on the indication. Operating in the first mode comprises transmitting the first control channel information and the second control channel information using common radio resources; and operating in the second mode comprises transmitting the first control channel information to the first wireless device and the second control channel information to the second wireless device using orthogonal radio resources. Methods and apparatus for obtaining control channel information in a first wireless device are also disclosed.

Abstract: The present disclosure relates to radio network communication. In one of its aspects, the present disclosure relates to a method, performed by a first APU, for sequential transmit precoding in a radio stripe system. The system comprises at least two APUs connected 5 in series from a CPU and serves at least two UEs. According to the method, channel estimates for channels to the served UEs are obtained and based on these, a precoding filter is determined. The precoding filter is going to be applied to signals that are to be transmitted from the first APU to the UEs. Thereafter, based on the determined precoding filter and the obtained channel estimates, effective precoded channels for the 0 signals to the UEs are determined. These represent the effective channel created after the precoding filter being applied to each channel for the UEs. The effective precoded channels are transmitted to at least one subsequent second APU. To be published with FIG.

Abstract: Embodiments herein disclose, e.g., an arrangement for handling radio signals, wherein the arrangement has an elongated housing. The elongated housing has at least one antenna processing unit (APU) and at least two groups of antenna elements, wherein each group of antenna elements includes antenna elements and a beamforming unit that generates one or more beams. The at least one APU is connected to both the groups of antenna elements.

Abstract: An antenna system includes at least a first antenna processing unit, APU1, and a second antenna processing unit, APU2, adjacently connected to each other through a serialized front haul. Each one of the APU1 and APU2 has at least two antenna elements. The antenna elements of APU1 are connected to their respective Radio Frequency, RF, chains via a first beamforming unit, and the antenna elements of APU2 are connected to their respective RF chains via a second beamforming unit. A network node configures the first beamforming unit and the second beamforming unit such that an absolute value of an angular difference between at least one of the beam directions generated by the first beamforming unit and each of the beam directions generated by the second beamforming unit exceeds or is equal to a threshold value.

Abstract: The present disclosure relates to radio network communication. In one of its aspects, the present disclosure relates to a method, performed by a first APU, for sequential receive combining in a radio stripe system. The system comprises at least two APUs connected in series to a CPU and serves at least two UEs. According to the method, channel estimates for channels to said served UEs are received and based on these, a receive combining filter is determined. The receive combining filter is to be applied to received data signals. Thereafter, based on the obtained channel estimates and the determined receive combining filter, effective channels from said served UEs are determined. These represent the effective channel created after the receive combining filter being applied to each channel for said served UEs. The effective channels are transmitted from said served UEs to at least one subsequent second APU.

Abstract: A method (200) of transmitting a block of data in a distributed MIMO system is disclosed. The distributed MIMO system comprises a plurality of access points (A1, . . . , AK), wherein access points (Aj) are grouped into a first set of M groups and a second set of M groups, different from the first set, wherein M is an integer. A first antenna port mapping assigns each group of the first set to a unique one of M antenna ports. A second antenna port mapping assigns each group of the second set to a unique one of M antenna ports. The method comprises transmitting (220) the block of data using both the first and the second antenna port mapping.

Abstract: A method of transmitting an amplitude shift keyed signal uses a multi-layered transmission over a plurality of transmit antennas with different precoding of different symbols for the respective layers. The method comprises obtaining a sequence of bits to be conveyed, keying the sequence of bits to a signal, precoding the signal to respective layer, and transmitting the precoded signal. A transmitter for transmitting the amplitude shift keyed signal, and a computer program for implementing the method are also disclosed.

Abstract: A disturbance mitigation method of a communication element for a distributed antenna system is disclosed. The communication element is associated with two or more antenna elements of the distributed antenna system. The method comprises acquiring channel condition information associated with at least two of a plurality of wireless communication devices served by the communication element, and partitioning the plurality of wireless communication devices into at least two groups based on the acquired channel condition information. The method also comprises, for each of the groups, determining respective pre-coding weights based on the acquired channel condition information, wherein the respective pre-coding weights of different groups are determined according to different disturbance mitigation approaches.

Abstract: A technique for assigning pilot signals to user equipments is described. The UEs access an RBS that provides radio access. As to a method aspect of the technique, an access burst including initial pilot signals is received from the UEs, wherein at least two of the UEs apply simultaneously the same initial pilot signal. A multicast channel to the at least two UEs is estimated based on the received access burst. A combined signal power received at the RBS is computed for the at least two UEs based on the estimated multicast channel. A message to the at least two UEs is sent using the multicast channel. The message is indicative of the combined signal power and assigns different pilot signals to the at least two UEs, wherein the assignment depends for each of the at least two UEs on the combined signal power and a signal power received at the respective UE.

Abstract: A method performed by a network node for broadcasting beamformed signals of a data transmission to a User Equipment (UE). For each specific data transmission from a number of data transmissions the network node allocates a set of Reference Signals, RS, for the data transmission, the number of RSs in the set of RSs being based on a measure of popularity for UEs receiving the specific data transmission. The network node sends an indication of the allocated set of SRs for each specific data transmission. The network node receives from a UE requesting a particular data transmission out of the number of data transmissions an RS from the set of RS allocated for the particular data transmission. The network node broadcasts beamformed signals of the particular data transmission. The signals are beamformed based on estimated composite channels from all UEs that transmit any RS included in the set of RS allocated for the particular data transmission.

Abstract: A method (200) of transmitting a block of data in a distributed MIMO system is disclosed. The distributed MIMO system comprises a plurality of access points (A1, . . . , AK), wherein access points (Aj) are grouped into a first set of M groups and a second set of M groups, different from the first set, wherein M is an integer. A first antenna port mapping assigns each group of the first set to a unique one of M antenna ports. A second antenna port mapping assigns each group of the second set to a unique one of M antenna ports. The method comprises transmitting (220) the block of data using both the first and the second antenna port mapping.

Abstract: A method of a receiver is used for receiving an amplitude shift keyed signal provided over a multi-layered transmission from a plurality of antennas with different precoding of different symbols for the respective layers. The method comprises receiving a sequence of signal values of the signal, estimating, from the sequence of signal values, channels for the respective layers, and selecting one of a plurality of detection methods based on a difference in quality between the estimated channels A receiver and a computer program are also disclosed.

Abstract: A method for detecting a data transmission, the method including measuring a signal level for each of a predetermined plurality of distinct time-frequency transmission resources within a first time interval, non-coherently summing the measured signal levels, and comparing the sum to at least a first threshold to determine whether a channel-hardened signal targeted to the wireless receiver is present. A corresponding method for encoding a channel-hardened signal comprises transmitting, in a first time interval and using M antenna ports and T1 time-frequency resources, an array X of M×T1 symbols, where each row of the array corresponds to one of the M antenna ports and each column of the array X corresponds to one of the first set of T1 time-frequency resources. X satisfies the expression XXH=aI, where XII is the conjugate transpose of X, I is an identity matrix, and ? is a constant.

Abstract: A method of transmitting an amplitude shift keyed signal uses a multi-layered transmission over a plurality of transmit antennas with different precoding of different symbols for the respective layers. The method comprises obtaining a sequence of bits to be conveyed, keying the sequence of bits to a signal, precoding the signal to respective layer, and transmitting the precoded signal. A transmitter for transmitting the amplitude shift keyed signal, and a computer program for implementing the method are also disclosed.