Mobile communication method and user terminal

A user equipment communicating with a base station by using a narrow band having a predetermined bandwidth, comprising:

• a controller, wherein
• the controller performs first communication related to control information by using a first narrow band in an n-th subframe,
• the controller performs second communication related to user data by using a second narrow band different from the first narrow band in an (n+1)-th subframe, and
• a symbol time region at an end of the n-th subframe and/or a symbol time region at a head of the (n+1)-th subframe are non-used regions for the user equipment to retune from the first narrow band to the second narrow band.

An apparatus for controlling a user equipment communicating with a base station by using a narrow band having a predetermined bandwidth, the apparatus comprising:

• a processor and a memory coupled to the processor, wherein
• the processor is configured to execute processes of
• performing first communication related to control information by using a first narrow band in an n-th subframe;
• and
• performing second communication related to user data by using a second narrow band different from the first narrow band in an (n+1)-th subframe, wherein
• a symbol time region at an end of the n-th subframe and/or a symbol time region at a head of the (n+1)-th subframe are non-used regions for the user equipment to retune from the first narrow band to the second narrow band.