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: 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.

Abstract: The present disclosure provides methods and devices for robustness enhancement in a wireless communication system comprising a plurality of network nodes and a wireless communication device which is configured to be connected to the plurality of network nodes including a first network node. Embodiments disclosed herein describe a first network node, a wireless communication device, a method in the first network node, a method in the wireless communication device, a wireless communication system and a non-transitory machine-readable medium. The method in the first network node comprises the operations of transmitting a data packet to the wireless communication device; generating assistance information indicating to the wireless communication device when to search for the same data packet from at least a second network node of the plurality of network nodes for soft combination; and transmitting the assistance information to the wireless communication device.

Abstract: A method in a terminal device for transmission to at least a first network device and a second network device over bundled Transmission Time Intervals (TTIs). The 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 blanking a portion of the first TTI, such that the rest of the first TTI does not overlap the second TTI.

Abstract: Embodiments of the present disclosure provide a method in a base station for coordinating resources in a wireless communications system 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: The present disclosure provides a method (200) in an access device for transmitting scheduling commands. The method (200) includes: transmitting (210) a scheduling command for scheduling a downlink data transmission in a first subframe where the downlink data transmission occurs; and transmitting (220) a replica of the scheduling command in each of one or more further subframes different from the first subframe.

Abstract: The present disclosure relates to a method used in a BS for scheduling a UE, and an associated BS. The method includes: determining four sets of PUCCH format 1b with channel selection resources, which include a part of CCE-mapped dynamic HARQ feedback resources reserved for the UE transmitting HARQ feedback to the BS by using PUCCH format 1a/1b, each set including two PUCCH format 1b with channel selection resources; selecting one of the four sets of PUCCH format 1b with channel selection resources as candidate resources, which are available for the UE transmitting HARQ feedback to the BS by using PUCCH format 1b with channel selection; and transmitting to the UE an indication indicating the selected one of the four sets of PUCCH format 1b with channel selection resources. The present disclosure also relates to a method used in a UE for transmitting HARQ feedback to a BS by using PUCCH format 1b with channel selection, and an associated UE.

Abstract: Embodiments of the present disclosure provide methods, apparatuses and computer program for facilitating reference signal transmission. An example method can be implemented at a base station in a wireless communication system for communicating with a terminal device. The terminal device is configured with a primary carrier and a secondary carrier for carrier aggregation. The method comprises determining a measurement gap. The measurement gap indicates a time interval for a terminal device to switch from the primary carrier to the secondary carrier for transmitting a reference signal to the base station over the secondary carrier and switch back to the primary carrier. The method also comprises triggering the terminal device to transmit the reference signal over the secondary carrier according to the measurement gap and obtaining a channel estimation based on the reference signal received from the terminal device during the measurement gap.

Abstract: The embodiments disclose a method of determining guard period for downlink-to-uplink switching in an access point of a time division duplex radio communication network. For each of a plurality of terminal devices served by the access point, the method comprising obtaining measurement information on uplink transmission delay of the terminal device due to the downlink-to-uplink switching and propagation delay; determining a time length of a guard period with respect to the terminal device based on the measurement information; assigning a time period scheduled for transmitting a uplink subframe with the time length as the guard period with respect to the terminal device; and informing the terminal device of the assignment.

Abstract: Embodiments of the present disclosure provide a method in a base station for random access preamble detection. The method comprises determining a frequency offset of a received uplink signal and adjusting the received uplink signal with the determined frequency offset. The method also comprises detecting, from the adjusted uplink signal, whether there is a random access preamble with a first false alarm value. Additionally, the method may further comprise detecting from the received uplink signal, whether there is a random access preamble with a second false alarm value, before determining the frequency offset of the received uplink signal. Determining the frequency offset of the received uplink signal may be performed in response that a random access preamble is detected with the second false alarm value, the second false alarm value being higher than the first false alarm value.

Abstract: Embodiments of the disclosure generally relate to enhancement of downlink control channel. A network device maps control information to a resource region. The control information is associated with data to be transmitted at a first subframe of a first cell. The resource region crosses a plurality of subframes and/or a plurality of cells. Then, the network device transmits the control information on the resource region to a terminal device.

Abstract: Embodiments of the present disclosure relate to methods and devices for data retransmission. In example embodiments, a method implemented in a first device is provided. According to the method, a RLC packet to a second device is transmitted on a RLC layer. It is determined whether an ACK feedback for the RLC packet is received from the second device during a predetermined RLC retransmission period. In response to missing the ACK feedback during the RLC retransmission period, the RLC packet is retransmitted to the second device on the RLC layer, regardless whether a NACK feedback for the previously transmitted RLC packet is received from the second device.