Primary cell switching in non-simultaneous uplink carrier aggregation scenarios

Abstract

The present disclosure relates to systems and methods for operating transceiver circuitry to communicate signals on various frequency ranges based on primary cell and/or secondary cell assignments. A controller associated with the transceiver circuitry may operate a receiver to receive a handover initiation packet using a first frequency range as a primary cell from a base station. The controller may adjust the receiver and a transmitter to use a second frequency range as the primary cell, to adjust the receiver and the transmitter to detach from the first frequency range as the primary cell, and to reset information corresponding to the first frequency range to enable attachment of the first frequency range to a secondary cell.

What is claimed is: 
     
         1 . A method for operating a base station, comprising:
 communicating, using a transceiver of the base station, with user equipment using a first frequency range assigned as a primary cell associated with bandwidth parts switching;   determining, by processing circuitry of the base station, to perform a handover of the primary cell from the first frequency range to a second frequency range;   generating, by the processing circuitry, a handover initiation packet, the handover initiation packet comprising a parameter configured to cause the handover in the user equipment;   sending, using the transceiver, the handover initiation packet to the user equipment using the first frequency range; and   communicating, using the transceiver, with the user equipment using the second frequency range as the primary cell after the user equipment performs the handover.   
     
     
         2 . The method of  claim 1 , comprising
 generating, by the processing circuitry, a control packet configured to assign the first frequency range as a secondary cell in the user equipment in response to receiving the control packet,   sending, using the transceiver, the control packet to the user equipment using the second frequency range as the primary cell, and   communicating, using the transceiver, with the user equipment using the first frequency range as the secondary cell and the second frequency range as the primary cell.   
     
     
         3 . The method of  claim 2 , comprising deactivating, by the processing circuitry, the first frequency range as the primary cell after assigning, by the processing circuitry, the second frequency range as the primary cell. 
     
     
         4 . The method of  claim 2 , comprising generating, by the processing circuitry, an indication of a media access control message comprising configuration data for assigning the first frequency range as the secondary cell. 
     
     
         5 . The method of  claim 2 , comprising
 receiving, using the transceiver, a random access channel preamble from the user equipment using the second frequency range as the primary cell,   transmitting, using the transceiver, a random access response as the control packet to the user equipment, the random access response generated as the control packet in response to the random access channel preamble, and   receiving, using the transceiver, a handover completion notification from the user equipment in response to the random access response, the handover completion notification indicating that the user equipment assigned the first frequency range as the secondary cell.   
     
     
         6 . The method of  claim 1 , comprising
 receiving, using the transceiver, an indication of a timing advance associated with a time delay experienced by the user equipment, and   communicating, using the transceiver, with the user equipment based on the timing advance.   
     
     
         7 . The method of  claim 1 , comprising receiving, using the transceiver, a handover completion notification from the user equipment without sending a corresponding a random access response to the user equipment. 
     
     
         8 . The method of  claim 1 , wherein the first frequency range corresponds to a subset of frequencies between 600 megahertz (MHz) and 700 MHz, between 2.5 gigahertz (GHz) and 3.7 GHz, between 25 GHz and 42 GHz, or any combination thereof. 
     
     
         9 . The method of  claim 1 , comprising
 assigning, by the processing circuitry, the second frequency range as the primary cell before detaching from the first frequency range as the primary cell, and   receiving, using the transceiver, a handover completion notification from the user equipment using the second frequency range after assigning the second frequency range as the primary cell.   
     
     
         10 . A base station comprising:
 a transmitter;   a receiver; and   one or more processors communicatively coupled to the transmitter and the receiver, the one or more processors configured to   cause the transmitter to transmit a handover initiation packet to user equipment using a first frequency range as a primary cell,   cause the receiver to receive a random access channel packet from the user equipment using a second frequency range as the primary cell,   cause the transmitter to send a random access response packet using the second frequency range as the primary cell to the user equipment, and   cause the receiver to receive a handover completion notification from the user equipment using the second frequency range as the primary cell.   
     
     
         11 . The base station of  claim 10 , wherein the user equipment is configured to transmit the handover completion notification to the base station in response to receiving the random access response packet. 
     
     
         12 . The base station of  claim 10 , wherein the one or more processors are configured to adjust the receiver and the transmitter to use the second frequency range as the primary cell after transmitting the handover initiation packet. 
     
     
         13 . The base station of  claim 10 , wherein the first frequency range corresponds to a set of frequencies between 600 megahertz (MHz) and 700 MHz, between 2.5 gigahertz (GHz) and 3.7 GHz, between 25 GHz and 42 GHz, or any combination thereof. 
     
     
         14 . The base station of  claim 10 , wherein the one or more processors are configured to adjust the receiver and the transmitter to detach from the first frequency range as the primary cell and reset information corresponding to the first frequency range after adjusting the receiver and the transmitter to use the second frequency range as the primary cell. 
     
     
         15 . The base station of  claim 10 , wherein the one or more processors are further configured to
 cause the transmitter to transmit a random access response to the user equipment,   cause the receiver to receive a handover completion message from the user equipment, and   cause the transmitter to transmit control information to the user equipment using the second frequency range as the primary cell.   
     
     
         16 . The base station of  claim 15 , wherein the control information comprises one or more medium access control layer signals. 
     
     
         17 . A base station, comprising:
 a receiver configured to receive signals in a first frequency range,   a transmitter; and   one or more processors communicatively coupled to the transmitter and the receiver, the one or more processors configured to   adjust the receiver and the transmitter to deactivate the first frequency range as a primary cell,   adjust the receiver and the transmitter to configure circuitry to activate a second frequency range as the primary cell,   operate the transmitter to transmit a control packet using the second frequency range as the primary cell to user equipment, and   adjust the receiver and the transmitter to use the first frequency range as a secondary cell at least in part by assigning the first frequency range as the secondary cell in response to transmitting the control packet.   
     
     
         18 . The base station of  claim 17 , wherein the one or more processors are configured to adjust the transmitter to transmit a handover initiation packet as a radio resource control protocol message in response to receiving a medium access control protocol message, a message transmitted via a physical layer signaling, a control signal, according to timing parameters or on a timing schedule, or any combination thereof, and cause the transmitter to transmit the handover initiation packet using the first frequency range as the primary cell to the user equipment. 
     
     
         19 . The base station of  claim 17 , wherein the first frequency range corresponds to a subset of frequencies between 600 megahertz (MHz) and 700 MHz, between 2.5 gigahertz (GHz) and 3.7 GHz, between 25 GHz and 42 GHz, or any combination thereof. 
     
     
         20 . The base station of  claim 17 , wherein the one or more processors are further configured to
 adjust the receiver and the transmitter to use the first frequency range as the secondary cell at least in part by assigning the first frequency range as the secondary cell in response to receiving a media access control address packet,   operate the transmitter to transmit a communication configuration to the user equipment, the communication configuration comprising indications of uplink allocations and downlink allocations to be observed by the user equipment for the first frequency range, the second frequency range, or both, the first frequency range and the second frequency range each corresponding to a respective component carrier,   operate the transmitter to transmit using the first frequency range, the second frequency range, or both, when a next communication period indicated by the communication configuration comprises a downlink allocation, and   operate the receiver to receive using the first frequency range, the second frequency range, or both, when the next communication period indicated by the communication configuration comprises an uplink allocation.   
     
     
         21 . A base station comprising:
 a transmitter;   a receiver; and   one or more processors communicatively coupled to the transmitter and the receiver, the   one or more processors configured to   operate the transmitter to transmit a handover initiation packet using a first frequency range as a primary cell to user equipment,   adjust the receiver and the transmitter to detach from the first frequency range as the primary cell and reset information corresponding to the first frequency range,   after detachment, adjust the receiver and the transmitter to use a second frequency range as the primary cell,   operate the receiver to receive a handover completion notification from the user equipment using the second frequency range as the primary cell,   operate the transmitter to transmit a control packet using the second frequency range as the primary cell to the user equipment, the control packet being configured to cause the user equipment to use the first frequency range as a secondary cell, and   adjust the receiver and the transmitter to use the first frequency range as the secondary cell at least in part by assigning the information corresponding to the first frequency range as the secondary cell.