Provided is a method of switching, by a user equipment (UE), a transmission chain across carriers, the method including determining to switch a first transmission chain for a transmission between a first carrier and a second carrier, determining a length of a switching gap during which no transmission or reception occurs on the first carrier and/or the second carrier, locating the switching gap within a switching duration, and switching the first transmission chain between the first carrier and the second carrier during the switching gap.

Provided is a method of switching, by a user equipment (UE), a transmission chain across carriers, the method including determining to switch a first transmission chain for a transmission between a first carrier and a second carrier, determining a length of a switching gap during which no transmission or reception occurs on the first carrier and/or the second carrier, locating the switching gap within a switching duration, and switching the first transmission chain between the first carrier and the second carrier during the switching gap.

Embodiments include methods performed by a target RAN controller for handling relocation of a UE connection from a source RAN controller during an ongoing wireless communication. Such methods include, when a distance between the UE and a border between source and target RAN controllers is below a threshold value, receiving from the source RAN controller an order to establish radio link(s) to be controlled by the target RAN controller for the ongoing wireless communication and establishing radio link(s) for the ongoing wireless communication accordingly. Such methods include, based on existence of certain conditions, receiving from the source RAN controller a request to initiate a procedure for relocating the UE connection from source to target RAN controller. Such methods include creating an RRC configuration to be used by the UE after the relocation to the target RAN controller and sending the created RRC configuration to the source RAN controller.

Embodiments include methods performed by a target RAN controller for handling relocation of a UE connection from a source RAN controller during an ongoing wireless communication. Such methods include, when a distance between the UE and a border between source and target RAN controllers is below a threshold value, receiving from the source RAN controller an order to establish radio link(s) to be controlled by the target RAN controller for the ongoing wireless communication and establishing radio link(s) for the ongoing wireless communication accordingly. Such methods include, based on existence of certain conditions, receiving from the source RAN controller a request to initiate a procedure for relocating the UE connection from source to target RAN controller. Such methods include creating an RRC configuration to be used by the UE after the relocation to the target RAN controller and sending the created RRC configuration to the source RAN controller.

A method for operating a centralized radio access network (C-RAN) having a plurality of base stations, wherein at least a portion of base station processing is performed at a centralized processing entity, and wherein a virtualized environment is provided by the centralized processing entity such that the plurality of base stations run in virtual machines, includes relocating base station processing from a first virtual machine that performs base station processing for a first base station that serves an initial cell to a second virtual machine by: introducing a target cell for which the second virtual machine performs base station processing, simultaneously transmitting, via at least a portion of antennas of the first base station, signals for both the initial cell and the target cell, and handing over user terminals that are assigned to the initial cell to the target cell.

In a method for accessing a legacy wireless network, a radio access network (RAN) node in the legacy wireless network receives an access message sent by a User Equipment (UE) attempting to access the legacy wireless network. The access message includes mobility management entity (MME) information identifying an MME accessed by the UE in an evolved network. The MME information is added by the UE from a temporary identity (ID) allocated by the MME to a first P-Temporary Mobile Station Identity (P-TMSI) in the access message. The RAN node selects a corresponding Serving GPRS Support Node (SGSN) in the legacy wireless network for the UE according to the first P-TMSI in the access message.

In a method for accessing a legacy wireless network, a radio access network (RAN) node in the legacy wireless network receives an access message sent by a User Equipment (UE) attempting to access the legacy wireless network. The access message includes mobility management entity (MME) information identifying an MME accessed by the UE in an evolved network. The MME information is added by the UE from a temporary identity (ID) allocated by the MME to a first P-Temporary Mobile Station Identity (P-TMSI) in the access message. The RAN node selects a corresponding Serving GPRS Support Node (SGSN) in the legacy wireless network for the UE according to the first P-TMSI in the access message.

Data distribution between mobile stations and external data paths is assigned to a new set of devices, distribution points. Each distribution point is independently coupled to mobile stations, also assigned to access points. Control elements operate to control the distribution points separately from the access points. Each access point maintains a substantially stateless link with each distribution point for which the two share a mobile station. Access points might exchange data with any one or more distribution points concurrently. Access points thus obtain greater bandwidth connectivity to external data paths. Mobile stations transfer between access points and transfer between distribution points independently. This has the effect that bandwidth connectivity between distribution points and external data paths have no particular requirement for VLAN separation. Mobile stations may roam among multiple Internet protocol subnets.

Data distribution between mobile stations and external data paths is assigned to a new set of devices, distribution points. Each distribution point is independently coupled to mobile stations, also assigned to access points. Control elements operate to control the distribution points separately from the access points. Each access point maintains a substantially stateless link with each distribution point for which the two share a mobile station. Access points might exchange data with any one or more distribution points concurrently. Access points thus obtain greater bandwidth connectivity to external data paths. Mobile stations transfer between access points and transfer between distribution points independently. This has the effect that bandwidth connectivity between distribution points and external data paths have no particular requirement for VLAN separation. Mobile stations may roam among multiple Internet protocol subnets.

A mobile communication method according to the present invention includes a step of transmitting, by a radio base station DeNB, a first downlink signal in a first subframe to a relay node RN, a step of transmitting, by the relay node RN, a second downlink signal in a second subframe to a mobile station UE, a step of notifying, by the relay node RN, the radio base station DeNB of information indicating “Half duplex inband Relay Node”, and a step of transmitting, by the radio base station DeNB, a transmission timing of R-PDCCH and R-PDSCH in a Un subframe to the relay node RN according to the notification.