What is claimed is:1. A method performed by a wireless device in a wireless communication system, the method comprising:establishing a dual connectivity (DC) with a first cell group (CG) and a second CG;receiving a configuration for a single uplink (UL) transmission informing a set of UL subframes for the first CG; andperforming the single UL transmission using the configuration for the single UL transmission while the DC is established,wherein the single UL transmission is performed such that a UL transmission to the first CG is performed in the set of UL subframes while a UL transmission to the second CG is not performed in the set of UL subframes, andwherein the configuration for the single UL transmission is used based on the single UL transmission being required by an intermodulation distortion (IMD) related to UL transmissions on the first CG and the second CG.2. The method of claim 1, wherein a UL subframe for the first CG and a UL subframe for the second CG are separated from each other in a time domain in a time division multiplexing (TDM) manner.3. The method of claim 2, further comprising:performing a UL transmission for an initial access procedure in the first CG irrespective of the configuration for the single UL transmission.4. The method of claim 1,wherein the first CG is a CG of long-term evolution (LTE), andwherein the second CG is a CG of new radio (NR).5. The method of claim 1, wherein, if a UL transmission to the first CG is scheduled in a UL subframe for the second CG, the scheduled UL transmission to the first CG is omitted irrespective of whether there is a UL transmission to the second CG in the UL subframe for the second CG.6. The method of claim 1, wherein the configuration is received before the second CG is activated.7. The method of claim 1, wherein the wireless device is in communication with at least one of a mobile device, a network, or autonomous vehicles other than the wireless device.8. A wireless device in a wireless communication system, the wireless device comprising:a memory;a transceiver; andat least one processor operatively coupled with the memory and the transceiver,wherein the at least one processor is configured to:establish a dual connectivity (DC) with a first cell group (CG) and a second CG;control the transceiver to receive a configuration for a single uplink (UL) transmission informing a set of UL subframes for the first CG; andcontrol the transceiver to perform the single UL transmission using the configuration for the single UL transmission while the DC is established,wherein the single UL transmission is performed such that a UL transmission to the first CG is performed in the set of UL subframes while a UL transmission to the second CG is not performed in the set of UL subframes, andwherein the configuration for the single UL transmission is used based on the single UL transmission being required by an intermodulation distortion (IMD) related to UL transmissions on the first CG and the second CG.9. The wireless device of claim 8, wherein a UL subframe for the first CG and a UL subframe for the second CG are separated from each other in a time domain in a time division multiplexing (TDM) manner.10. The wireless device of claim 8, wherein the at least one processor is further configured to control the transceiver to perform a UL transmission for an initial access procedure in the first CG irrespective of the configuration for the single UL transmission.11. The wireless device of claim 8,wherein the first CG is a CG of long-term evolution (LTE), andwherein the second CG is a CG of new radio (NR).12. A non-transitory computer-readable medium having stored thereon a plurality of instructions for a wireless device in a wireless communication system, wherein the plurality of instructions cause the wireless device to:establish a dual connectivity (DC) with a first cell group (CG) and a second CG;receive a configuration for a single uplink (UL) transmission informing a set of UL subframes for the first CG; andperform the single UL transmission using the configuration for the single UL transmission while the DC is established,wherein the single UL transmission is performed such that a UL transmission to the first CG is performed in the set of UL subframes while a UL transmission to the second CG is not performed in the set of UL subframes, andwherein the configuration for the single UL transmission is used based on the single UL transmission being required by an intermodulation distortion (1 MB) related to UL transmissions on the first CG and the second CG.