Telefonaktiebolaget Lm Ericsson (publ)

Emil Björnson

Erik G Larsson

Pål Frenger

Martin Hessler

Leif Wilhelmsson

Reza Moosavi

Marcus Karlsson

Giovanni Interdonato

Jan Hederen

Hei Victor Cheng

Eric G Larsson

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.

Arrangement and method performed therein for handling communication

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.

Apparatuses and methods for sequential transmit precoding

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.

Method and network node with improved beamforming

A method of operating a distributed MIMO system is disclosed. The distributed MIMO system is configured to serve a plurality of wireless communication devices (u, . . . , u). The distributed MIMO system comprises a number of access points (A, . . . , A), each comprising a time circuit () configured to keep track of a local time of the access point (A, . . . , A). The method comprises performing () an intra-group synchronization procedure for a group (G) of at least three access points (A-A). The intra-group synchronization procedure comprises, for each access point (A) in the group (G), transmitting (T), from that access point (A), a synchronization signal and obtaining (O) a transmission time indicator indicating a transmission time of that synchronization signal in the local time of that access point (A). Furthermore, the intra-group synchronization procedure comprises receiving (R, R), by each of the other access points (A, A) in the group, the synchronization signal and obtaining (O, O) reception time indicators indicating reception times, in the local times of the other access points (A, A), when the synchronization signal was received by the other access points (A, A) in the group.

Distributed MIMO synchronization

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.

Receiver, communication apparatus, method and computer program for receiving an amplitude shift keyed signal

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.

Methods and apparatus for transmitting and receiving control channel information

A method () of transmitting a block of data in a distributed MIMO system is disclosed. The distributed MIMO system comprises a plurality of access points (A, . . . , A), wherein access points (A) 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 () the block of data using both the first and the second antenna port mapping.

Transmissions of blocks of data in distributed MIMO systems

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. Furthermore, the method comprises transmitting a signal comprising respective symbols intended for corresponding ones of the plurality of wireless communication devices, wherein the symbols intended for wireless communication devices of each group are pre-coded using the determined respective pre-coding weights of the group, and wherein the pre-coded symbols of at least two of the groups are super-positioned to form the signal. Corresponding method of a wireless communication device is also disclosed, as well as corresponding apparatuses, communication element, distributed antenna system, wireless communication device and computer program product.

Disturbance mitigation

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.

Transmitter, communication apparatus, method and computer program for transmitting amplitude shift keyed signals using multiple transmit antennas

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.

Technique for assigning pilot signals to user equipments

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&#xd7;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 XX=aI, where Xis the conjugate transpose of X, I is an identity matrix, and &#x3b1; is a constant.

Reliable communication to energy-detection receivers

Embodiments of systems and methods relating to a first radio device (UE) and a second radio device (base station) are disclosed. In some embodiments, a method implemented in the second radio device for adaptation of transmission over a radio channel is described. The method comprises determining a condition of the radio channel in which the radio channel exhibits an invariance of statistics and transmitting a data symbol to the first radio device via the radio channel. The method further comprises receiving a quality report of the radio channel from the first radio device based on the data symbol when a statistical characterization of the radio channel exceeds a predetermined threshold. The transmission over the radio channel is adapted by the second radio device based on the received quality report.

Reporting of radio channel quality

Method performed by a first communication device () for adapting a pre-coder used by a second communication device () to transmit radio signals using beamforming to a third communication device (). The first communication device (), the second communication device (), and the third communication device () operate in a wireless communications network (). The first communication device () adapts (), over a single time period of transmission of the radio signals, the pre-coder used by the second communication device () to transmit the radio signals to the third communication device () using beamforming. The adapting () is based on a change, over the single time period, in a state of a channel used to transmit the radio signals. The state is measured by the second communication device ().

First communication device and methods performed thereby for transmitting radio signals using beamforming to a second communication device

A method implemented in a first radio device (UE) for quality reporting of a radio channel () comprising: Determining a condition of the radio channel and entering a monitoring phase if the condition of the radio channel exhibits an invariance of statistics of the radio channel (), Receiving at least one data symbol via said radio channel during the monitoring phase (), Determining a statistical characterization of the radio channel based on the received data symbol (), and Reporting a quality of the radio channel () to a second radio device if the statistical characterization exceeds a predetermined threshold ().

A method is disclosed of a first wireless communication apparatus of a communication system operating in a hardened channel environment. The method comprises determining a transmission power to be used by a second wireless communication apparatus of the communication system for transmission of a signal carrying control information, participating in communication involving the signal transmitted using the determined transmission power, and using the determined transmission power to discriminate between the second wireless communication apparatus and one or more third wireless communication apparatus. The second and one or more third wireless communication apparatuses may be comprised in respective user equipments of a plurality of user equipments associated with a network node of the communication system. The first wireless communication apparatus may be comprised in the network node. Then, determining the transmission power may comprise determining respective transmission powers to be used by each of the user equipments in the plurality.

Growing community of inventors

Linköping, Sweden

Emil Björnson