A method for limiting a spurious emission, and a user equipment (UE) thereof are discussed. The method according to one embodiment includes configuring a radio frequency (RF) unit of the UE to use a band 1; if the RF unit is configured to use the band 1, controlling the RF unit of the UK to limit a maximum level of spurious emission to −50 dBm for protecting another UE using a band 5; and transmitting an uplink signal through the configured RF unit. The band 1 includes an uplink operating band of 1920-1980 MHz and a downlink operating band of 2110-2170 MHz. The band 5 includes an uplink operating band of 824-849 MHz and a downlink operating band of 869-894 MHz.

The apparatus may be a base station. The apparatus processes a plurality of synchronization signals by performing time-division multiplexing (TDM) of at least one of a plurality of first synchronization signals of different types and at least one of the plurality of second synchronization signals of different types, the plurality of synchronization signals including the plurality of first synchronization signals and the plurality of second synchronization signals. The apparatus transmits the processed synchronization signals to a user equipment (UE).

The apparatus may be a base station. The apparatus processes a first group of synchronization signals. The apparatus processes a second group of synchronization signals. The apparatus performs a first transmission by transmitting the processed first group of the synchronization signals in a first synchronization subframe. The apparatus performs a second transmission by transmitting the processed second group of the synchronization signals in a second synchronization subframe.

The apparatus may be a base station. The apparatus sets a first numerology for at least one synchronization signal of one or more synchronization signals to be different from a second numerology for at least one data signal of one or more data signals. The apparatus transmits the one or more synchronization signals to a user equipment (UE) based on the first numerology. The apparatus transmits the one or more data signals to the UE based on the second numerology.

Device-to-device (D2D) transmissions by a wireless device may interfere with base station reception of other signals. To mitigate this interference, the wireless device estimates the path loss between itself and the base station. The path loss and the current D2D transmission power level are used to estimate the amount of interference the base station is experiencing as a result of the D2D transmissions from the wireless device. Based on the estimated interference experienced by the base station, the wireless device increases the robustness of the MCS being used and decreases the transmission power level by a corresponding amount. By decreasing the D2D transmission power level, less interference will be experienced by the base station. By increasing the robustness of the MCS, the impact of the reduced D2D transmission power level is mitigated.

A boundary of a wireless network is monitored for incoming wireless signals that may interfere with an ability of a first wireless computing device to connect to the wireless network within the boundary of the wireless network. For an incoming wireless signal determined to interfere with the ability of the first wireless computing device to connect to the wireless network within the boundary of the wireless network, a directional opposing outgoing wireless signal is emitted to counteract the incoming wireless signal and to stop the incoming wireless signal from further interfering with the ability of the first wireless computing device to connect to the wireless network within the boundary of the wireless network.

A transmission method is provided for a communication system in which communications using a plurality of communication methods having different transmission parameters are performed at the same frequency (in frequency bands that at least partially overlap with each other). The transmission method includes: generating a first symbol group that includes a control symbol for causing a communication partner apparatus to recognize that communication using a first communication method is to be performed and a second symbol group that includes a data symbol for the first communication method; transmitting the first symbol group at a first transmit power; and transmitting the second symbol group at a second transmit power that is smaller than the first transmit power.

A terminal apparatus includes circuitry and a transmitter. The circuitry, in operation, generates a reference signal using a cyclic shift value and an orthogonal sequence, which are associated with each other. The orthogonal sequence is one of two orthogonal sequences corresponding to a first orthogonal sequence [1, 1] and a second orthogonal sequence [1, −1]. The cyclic shift value is one of 12 cyclic shift values ranging from 0 to 11. The transmitter, in operation, transmits the reference signal multiplexed with a data signal. Two of the cyclic shift values having a difference of 6 are respectively associated with the two orthogonal sequences.

A wireless communication base station apparatus prevents degradation of throughput of LTE terminals, even when LTE terminals and LTE+ terminals are present together. A setting section sets in each subframe a resource block in which is arranged a reference signal that is employed solely by LTE+ terminals, based on the pattern of arrangement of reference signals employed solely by LTE+ terminals. As to symbols that are mapped to antennas (110-1) to (110-4), an arrangement section arranges the characteristic cell reference signals employed by both LTE terminals and LTE+ terminals in all of the resource blocks in a single frame. In contrast, as to symbols that are mapped to antennas (110-5) to (110-8), the arrangement section arranges in some of the resource blocks, that are set in accordance with the setting results input from a setting section, the characteristic cell reference signals that are employed solely by the LTE+ terminals.

One embodiment of the present invention relates to a method for transmitting a signal from a device-to-device (D2D) terminal in a wireless communication system, which is a signal transmission method comprising: generating a reference signal sequence; mapping the reference signal sequence on specific symbols; and transmitting a signal comprising the reference signal sequence, wherein the specific symbols are shifted n and m symbols, respectively, away from the fourth symbol of each slot toward a time axis.