Patent ID: 7242934

Claim:
A mobile communication terminal comprising: plural radio means within said mobile communication terminal for plural communication systems being different from one another, which establishes, connects, and disconnects radio lines; and measure communication quality at said plural communication systems; a controlling means within said mobile communication terminal, which controls each of said plural radio means so that each of said plural radio means establishes, connects, and disconnects radio lines, said controlling means measuring said communication quality at each of said plural different communication systems and executing handover from one of said plural communication systems to another one of said plural communication systems by changing the operation of said plural radio means; and an operating means within said mobile communication terminal which exchanges information with a user of said mobile communication terminal, wherein: in case that a communication system which is used after handover operation was executed is designated via said operating means by said user, said controlling means controls to execute said handover operation based on the designation of said user; when said handover operation designated by said user is impossible, said controlling means outputs this situation that said handover operation designated by said user is impossible via said operating means.