Provided are a method for contention-based random access, a network device and a terminal device. The method comprises: a network device receiving, on a first uplink carrier or a second uplink carrier, a first preamble sent by a terminal device, a frequency point of the first uplink carrier being different from a frequency point of the second uplink carrier; and the network device sending to the terminal device a media access control (MAC) protocol data unit (PDU), wherein the MAC PDU comprises a first media access control (MAC) random access response (RAR) corresponding to the first preamble.

A base station may transmit, to a wireless device, one or more messages comprising configuration parameters for a primary cell and a secondary cell. The configuration parameters may indicate a deactivation timer for the secondary cell and a bandwidth part (BWP) inactivity timer for the primary cell. The base station may start the deactivation timer in response to activating the secondary cell. The base station may start the BWP inactivity timer in response to switching an active BWP of the primary cell. The base station may stop the BWP inactivity timer of the primary cell based on triggering a random-access procedure for the secondary cell. In response to the deactivation timer of the secondary cell expiring during the random-access procedure, the base station may restart the BWP inactivity timer of the primary cell.

A method is disclosed of a transmitter configured to transmit a physical layer packet in accordance with a listen-before-talk procedure. The method includes acquiring an indication of a specific time for channel estimation, providing the physical layer packet with at least one measurement signal for channel estimation based on the specific time, and transmitting the physical layer packet. In some embodiments, the physical layer packet is provided with a plurality of midambles, wherein each midamble includes one or more measurement signals for channel estimation. In some embodiments, the physical layer packet is provided with a floating midamble which comprises one or more measurement signals for channel estimation. A method is also disclosed of a receiver configured to receive a physical layer packet transmitted in accordance with a listen-before-talk procedure.

A system, wireless device and network node for managing interference from aggressor private networks are provided. According to one or more embodiments, a wireless device that is configured to communicate with a serving network node is provided. The wireless device includes processing circuitry configured to cause transmission of random access (RA) signaling to a first network node where the RA signaling is configured to indicate that the first network node is causing interference at the wireless device.

Disclosed is a method for transmitting and receiving signals to enable a terminal to perform a random access channel procedure (RACH procedure) in an unlicensed band. In particular, the method comprises: transmitting an uplink signal including a first physical random access channel (PRACH) and a first physical uplink shared channel (PUSCH) to a base station; and receiving, from the base station, a downlink signal related to contention resolution in response to the uplink signal, wherein a power ramping counter is used to set the transmission power of the uplink signal, and the value of the power ramping counter may be increased on the basis of a transmission spatial beam for the transmission of the uplink signal being configured in the same manner as a transmission spatial beam for the transmission of a PRACH prior to the uplink signal.

Systems and methods for wireless communications are disclosed herein. In some embodiments, a wireless communication method includes indicating, by a base station to a wireless communication device, at least one set of resources for network access and performing, by the base station, a network access procedure with the wireless communication device based on the at least one indicated set of resources for network access.

The present invention is designed so that communication can be performed adequately even when the number of component carriers (CCs) that can be configured in a user terminal is expanded and/or when CA is executed using unlicensed CCs. A user terminal communicates with a radio base station using carrier aggregation, and has a transmission section that transmits UL signals via each CC, and a control section that controls the transmission operations in the transmission section, and, when a plurality of CCs, including at least a first CC, which corresponds to a primary CC of an existing system, and a third CC, which is different from the first CC and a second CC that corresponds to a secondary CC of the existing system, are configured, the control section applies, to the third CC, random access operations that are different from those of the first and second CCs.

A wireless transmission scheduling method is proposed. The method may be a synchronous media access control (MAC) wireless transmission scheduling method optimized for a user datagram protocol (UDP) of a personal wireless network-based data transmission system. The method may include setting a superframe period, a beacon period, and a contention period by a master station in a network. The method may also include calculating transmission periods of one or more slave stations participating in the network and a transmission period of the master station. The method may further include transmitting information about the calculated transmission periods of the one or more slave stations to the one or more slave stations participating in the network. The method may further include transmitting data by the one or more slave stations and the master station in the transmission periods assigned to the one or more slave stations and the master station.

A wireless device receives one or more messages indicating a first transmission occasion for a physical uplink control channel (PUCCH) resource and indicating a second transmission occasion for the PUCCH resource. The wireless device receives downlink control information (DCI) indicating a transmission configuration indicator (TCI) state and indicating the PUCCH resource. The wireless device skips transmission, via the first transmission occasion of the PUCCH resource and based on a first listen before talk (LBT) procedure indicating a busy channel on the first transmission occasion, of an acknowledgment of the receiving the DCI indicating the TCI state. The wireless device transmits, based on a second LBT procedure indicating an idle channel on the second transmission occasion, the acknowledgment via the second transmission occasion of the PUCCH resource.

A method and apparatus for requesting uplink resources in a wireless communication system is provided. A user equipment determines whether a scheduling request for requesting uplink resources is triggered. If the scheduling request is triggered, the user equipment transmits a first set of frequency domain sequences and a second set of frequency domain sequences in a subframe.