Abstract: The present disclosure provides a method (200) in a network device for data transmission over a front haul interface between a first unit and a second unit. The method (200) includes: compressing (210), at the first unit, time domain data in frequency domain and/or spatial domain; transmitting (220) the compressed time domain data along with an associated compression parameter over the front haul interface from the first unit to the second unit; and decompressing (230), at the second unit, the compressed time domain data based on the compression parameter.

Abstract: A terminal device for transmission to at least a first network device and a second network device over bundled Transmission Time Intervals (TTIs). A method comprises determining that a first TTI for transmission to the first network device overlaps a second TTI for transmission to the second network device based on a first Timing Advance (TA) value associated with the first network device and a second TA value associated with the second network device; and requesting from the first and second network devices a first and a second transmission grants, respectively, based on the first and second TA values, such that an order of the first and second transmission grants requested is based on values of the first and second TA values.

Abstract: A method for managing a Massive Multiple Input Multiple Output (M-MIMO) base station is disclosed. The method comprises receiving from a neighbour base station a notification of load conditions at the neighbour base station (110) and obtaining measurements on communication resources associated with the neighbour base station (120). The method further comprises determining whether there exists within a spatial distribution of traffic served by the neighbour base station a region having a concentration of traffic which is above a threshold level (130), and, if such a region exists, and if a condition for load transfer from the neighbour base station is fulfilled, causing at least one reference signal transmitted by the M-MIMO base station to be transmitted towards the determined region with a signal strength sufficient to trigger handover of a device in the determined region to the M-MIMO base station (160).

Abstract: Embodiments of the present disclosure provide methods, apparatus and computer readable storage medium for controlling data retransmission in a multi-user system. A method comprises determining whether data transferred by any of multiple users are received unsuccessfully. The multiple users share a same resource in a feedback channel, for carrying feedback information of whether or not data transferred by respective users are received successfully. When data transferred by any of the multiple users are received unsuccessfully, the method also comprises causing data retransmission in a first retransmission mode or a second retransmission mode. In the first retransmission mode, positive feedback is sent via the same resource to the multiple users, and adaptive retransmission is triggered for the users whose data are received unsuccessfully.

Abstract: Methods and apparatuses for power control are disclosed for in-device coexistence (IDC). According to an embodiment, a first radio access technology (RAT) unit measures a metric indicating relative strength of traffic received by the first RAT unit with respect to IDC interference from a second RAT unit that is co-located with the first RAT unit on a user equipment (UE). The first RAT unit determines whether a condition to adjust transmission power of the second RAT unit is satisfied based at least on the measured metric. When the condition is satisfied, an adjustment indication related to a desired adjustment of the transmission power is generated based at least on the measured metric. The adjustment indication is sent to the second RAT unit.

Abstract: A data exchange method in a Coordinated Multi-Point (CoMP) system, including an assistant point and a converging point. One method comprises selecting a predetermined number of subbands with the best channel quality, and exchanging user data of the selected subbands. Only part of the user data received at the assistant point is transmitted to the converging point. The requirement on the transport network capacity is thus loosened. By transmitting data with the best channel quality, a good enough gain is guaranteed.

Abstract: A method for antenna calibration is proposed. The method may comprise setting a first control unit to a first operation mode. The first control unit may be located on a first antenna path of a first antenna array which has a plurality of antennas. Under the first operation mode of the first control unit, a calibration signal for the first antenna path can be isolated from interference. The method may further comprise obtaining a measurement based at least partly on the calibration signal for the first antenna path. The method may further comprise performing antenna calibration for the plurality of antennas of the first antenna array based at least partly on the obtained measurement.

Abstract: A method performed by a network node, for handling link adaption (LA) of a channel. The network node obtains a channel quality value for each Transmission Time Interval (TTI) in a set of TTIs. The network node estimates a probability that a specific channel quality will occur from the obtained channel quality values for the set of TTIs based on a distribution of channel quality values. The network node further determines a set of transmission parameters which optimizes a target function of LA, based on the estimated probability for the channel quality, wherein each set of transmission parameters is mapped to a channel quality which is required for a successful reception.

Abstract: The present disclosure provides a method implemented in a wireless communication device for determining an Angle of Arrival (AOA) of a wireless signal received at the wireless communication device. The method comprises estimating the AOA of the wireless signal, determining that the estimated AOA is ambiguous and acquiring signal strength measurements for the wireless signal received at two other wireless communication devices, which are located substantively symmetrically about a normal of the wireless communication device's antenna array. The method further comprises disambiguating the estimated AOA based on a comparison of the acquired signal strength measurements. The present disclosure also provides the wireless communication device as well as a Radio Base Station (RBS) comprising the wireless communication device.

Abstract: A wireless communications system (10) and a method therein for transmission of a downlink signal in a wireless communications network (100) supporting beamforming. The system estimates uplink channel information for a radio link from a wireless device (120) to a radio network node (110). Further, the system obtains downlink beamforming information related to the estimated uplink channel information from a machine learning unit (300). The machine learning unit comprises relationships between beamforming information and uplink channel information determined based on stored pairs of reported downlink beamforming information and measured uplink channel information. The obtained downlink beamforming information is applicable for the radio cell sector. Furthermore, the system transmits, towards the wireless device (120), a beamformed downlink signal using the obtained downlink beamforming information.

Abstract: The present disclosure provides a method in a network device for transmission of Narrow Band-Internet of Things (NB-IoT) data between a Radio Equipment Control (REC) node and a Radio Equipment (RE) node over Common Public Radio Interface (CPRI). The method comprises: transmitting the NB-IoT data from the REC node to the RE node or from the RE node to the REC node in a Control and Management (C&M) region of a CPRI frame. The NB-IoT data is frequency-domain data.

Abstract: One embodiment relates to a method for transmitting a random access preamble in a transmitting sub-frame at a terminal device. The method (200) comprises: creating a random access preamble such that it comprises a plurality of random access sequences (S210); dividing the plurality of random access sequences into a number N, of groups, each of groups including two or more random access sequences (S220); performing code division multiplexing with respect to the groups of the plurality of random access sequences in a frequency domain, based on an orthogonal cover code selected for the terminal device from a pre-defined code set (S230); and transforming signals after the code division multiplexing into the time domain (S240). There are provided corresponding methods and devices.

Abstract: One embodiment of the present disclosure relates to a method for operating in a terminal device for downlink flow control. The terminal device receives duplicated packets from a first network node device and one or more secondary network node devices. The method comprises measuring downlink transmission information for the first network node device and the one or more secondary network node devices; deciding downlink flow control information based on the measured downlink transmission information; and sending the downlink flow control information to at least the first network node device. According to other aspects of the present disclosure, there are provided corresponding methods and devices.

Abstract: A method is implemented in a digital unit connected with a plurality of distributed antennas including a first antenna, a second antenna and a third antenna. The method comprises: causing transmitting a first signal from the first antenna, a second signal from the second antenna, and a third signal from the third antenna in a same frequency resource; obtaining a receiver and transmitter side loop-back phase difference between the first antenna and the second antenna based on the first signal received at the third antenna, the second signal received at the third antenna, the third signal received at the first antenna, and the third signal received at the second antenna; and obtaining estimations of a time delay difference and an initial phase difference between the first and second antennas based on the obtained loop-back phase difference.

Abstract: Embodiments of the disclosure generally relate to data transmission feedback. A terminal device receives a data packet transmitted from one or more network devices of the plurality of network device and determine whether triggering a feedback based on one or more of the received data packet, the monitored network devices and a timer Y at the terminal device. Latency for feedback of data transmission can be reduced and reliability can be improved.

Abstract: A terminal device for transmission to at least a first network device and a second network device over bundled Transmission Time Intervals (TTIs). A method comprises determining that a first TTI for transmission to the first network device overlaps a second TTI for transmission to the second network device based on a first Timing Advance (TA) value associated with the first network device and a second TA value associated with the second network device; and requesting from the first and second network devices a first and a second transmission grants, respectively, based on the first and second TA values, such that an order of the first and second transmission grants scheduled is based on values of the first and second TA values.

Abstract: Embodiments of the present disclosure relate to methods and devices for reference signal transmission and measurement. In example embodiments, according to a method implemented in a network device is provided, a report related to a measurement of a first reference signal is received from a terminal device. The first reference signal has been sent from the network device to the terminal device according to a first periodicity. Then an indication of a second periodicity for receiving a second reference signal is sent to the terminal device based on the report. The second reference signal is associated with the first reference signal.

Abstract: Embodiments of the present disclosure provide a method in a base station for coordinating resources in a wireless communications systems with carrier aggregation in which a first group of terminal devices is served by a primary cell and one or more secondary cells under control of the base station. The method comprises obtaining information indicating arrival of a second group of terminal devices at coverage of the base station. A speed of any terminal device of the second group is higher than a speed of any terminal device of the first group. The method also comprises releasing resources on at least one secondary cell of the one or more secondary cells and allocating the released resources to the second group of terminal devices.

Abstract: A method performed by a first communication device (101) operating in a wireless communications network (100). The first communication device (101) obtains (301) a grant for an uplink transmission to a second communication device (102) operating in the 5 wireless communications network (100). The grant comprises a first indication of one or more first sets of parameters for transmission. The first communication device (101) selects (302) a second set of parameters for the uplink transmission based on: i) the indicated one or more first sets of parameters, and ii) one or more quality of service requirements of an information to be transmitted in the uplink transmission. The first 10 communication device (101) then initiates (304) sending the uplink transmission to the second communication device (102), based on the selected second set of parameters.

Abstract: A method for antenna calibration is proposed. The method may comprise setting a first control unit to a first operation mode. The first control unit may be located on a first antenna path of a first antenna array which has a plurality of antennas. Under the first operation mode of the first control unit, a calibration signal for the first antenna path can be isolated from interference. The method may further comprise obtaining a measurement based at least partly on the calibration signal for the first antenna path. The method may further comprise performing antenna calibration for the plurality of antennas of the first antenna array based at least partly on the obtained measurement.