A method for transmitting an uplink signal for a terminal configured to support at least one transmission time interval (TTI) length in a wireless communication system, according to one embodiment of the present invention, is performed by the terminal and comprises the steps of: receiving, in multiple downlink cells, a downlink data channel; and transmitting, in at least one uplink cell, uplink control information for the downlink data channel, wherein the at least one uplink cell corresponds to at least one of the multiple downlink cells, and downlink cells having the same TTI length or a TTI length of one group may correspond to one uplink cell.

Systems, methods and computer software are disclosed for providing core High Availability (HA) for a wireless network. In one embodiment, a method is disclosed, comprising: providing a first node, a second node and a third node; allocating a set of locally generated Tunnel Endpoint Identifiers (TEIDs) for UEs anchored on the second node; detecting, by a first node, a second node having a connectivity issue; and migrating a User Equipment (UE) connected to the second node to a third node which is accessible; using the set of locally generated TEIDs to identify the UE migration.

A wireless transmitter/receiver generates a first signal which notifies timing of a time slot allocated to each wireless station device, a conversion unit converts the first signal into an optical signal, and each of a plurality of antenna units converts the first signal from the optical signal into an electrical signal and transmits the electrical signal wirelessly. The wireless station device transmits a second signal at the timing reported by the first signal. Each of the plurality of antenna units converts the second signal wirelessly received from each wireless station device into an optical signal, and the conversion unit converts the second signal from the optical signal into an electrical signal. The wireless transmitter/receiver calculates, for each wireless station device, a transmission delay by using a difference between a reception time of the second signal and a reception time of a signal transmitted at the allocated timing by the wireless station device when it is assumed that there is no transmission delay. The wireless transmitter/receiver determines guard time between the time slots allocated to the wireless station devices based on the transmission delays of the wireless station devices.

An apparatus and method for broadcast signal frame using layered division multiplexing are disclosed. An apparatus for generating broadcast signal frame according to an embodiment of the present invention includes a combiner configured to generate a multiplexed signal by combining a core layer signal and an enhanced layer signal at different power levels; a power normalizer configured to reduce the power of the multiplexed signal to a power level corresponding to the core layer signal; a time interleaver configured to generate a time-interleaved signal by performing interleaving that is applied to both the core layer signal and the enhanced layer signal; and a frame builder configured to generate a broadcast signal frame including a bootstrap and a preamble using the time-interleaved signal.

A large number of degrees for relays of optical signals transmitted via optical paths in the degrees is secured. A wavelength cross-connect device 20A performs a relay by splitting optical signals from respective degrees indicated by reference numerals 40l, 40h, 40m, 40q, each of the degrees being provided by optical fibers, via respective optical couplers and outputting the split optical signals to output sides of the plurality of degrees via respective WSSs 23a to 23d. As the optical couplers, variable couplers 27a to 27d whose respective splitting ratios, each of which is a ratio of optical signal power losses in splitting an optical signal, are variable are used. The wavelength cross-connect device 20A includes a control unit 26 that performs control to change the splitting ratios in such a manner as to eliminate an imbalance among OSNR margins of the output sides of the degrees in which a plurality of optical paths transmitting the split optical signals extend. The control unit 26 calculates the margins for the respective optical paths transmitting the split optical signals via the variable couplers 27a to 27d, for each of the output sides of the degrees. The control unit 26 performs control to, based on respective smallest margins of the degrees in all the margins, change the splitting ratios of the variable couplers 27a to 27d in such a manner as to eliminate an imbalance between the margins of the degrees.

Example embodiments of the invention provide at least a method and apparatus to perform communications between an entity in a cell and a neighboring cell of a cluster of cells of a communication network a request signal indicating a desire to change from a first common radio frame configuration with the neighboring cell to a second different common radio frame configuration; and in response to the request signal, receiving at least one feedback signal from the neighboring cell to perform one of: implementing the change at the cell from the first common radio frame configuration to the second common radio frame configuration when the at least one feedback signal indicates acceptance of the change, and implementing the change at the cell from the first common radio frame configuration to a different individual local radio frame configuration when the at least one feedback signal indicates rejection of the change.

A method and apparatus of a user equipment (UE) for transmitting and receiving data in a wireless communication system. The UE receives first time division duplex (TDD) uplink-downlink configuration information for a first cell and second TDD uplink-downlink configuration information for a second cell, determines whether a subframe in the first cell is a special subframe and the subframe in the second cell is a downlink subframe according to the first and second TDD uplink-downlink configuration information, and determine, if the subframe in the first cell is the special subframe and the subframe in the second cell is the downlink subframe, not to receive a signal on the second cell in orthogonal frequency division multiplexing (OFDM) symbols that overlaps with at least one of a guard period (GP) or uplink pilot time slot in the first cell.

A method and apparatus of a user equipment (UE) for transmitting and receiving data in a wireless communication system. The UE receives first time division duplex (TDD) uplink-downlink configuration information for a first cell and second TDD uplink-downlink configuration information for a second cell, determines whether a subframe in the first cell is a special subframe and the subframe in the second cell is a downlink subframe according to the first and second TDD uplink-downlink configuration information, and determine, if the subframe in the first cell is the special subframe and the subframe in the second cell is the downlink subframe, not to receive a signal on the second cell in orthogonal frequency division multiplexing (OFDM) symbols that overlaps with at least one of a guard period (GP) or uplink pilot time slot in the first cell.

A communication apparatus includes a receiver and a decoder. The receiver includes a plurality of antenna elements and, in operation, receives from a base station apparatus a modulated signal mapped to one of a plurality of subframes defined in a frame corresponding to a communicable range to which the communication apparatus belongs. The plurality of subframes are defined by time-division, frequency-division, or time-and-frequency division of the frame. A maximum number of modulated signals that can be simultaneously transmitted in a subframe from the base station apparatus varies depending on the communicable range. The decoder, in operation, decodes the received modulated signal.

A communication apparatus includes a receiver and a decoder. The receiver includes a plurality of antenna elements and, in operation, receives from a base station apparatus a modulated signal mapped to one of a plurality of subframes defined in a frame corresponding to a communicable range to which the communication apparatus belongs. The plurality of subframes are defined by time-division, frequency-division, or time-and-frequency division of the frame. A maximum number of modulated signals that can be simultaneously transmitted in a subframe from the base station apparatus varies depending on the communicable range. The decoder, in operation, decodes the received modulated signal.