Radio antenna apparatus provided with controller for controlling SAR and radio communication apparatus using the same radio antenna apparatus

A radio antenna apparatus comprising:

• a first antenna;
• a second antenna;
• a switch device for switching over so as to connect said second antenna to a ground of a housing of a radio communication apparatus including a radio communication circuit, that is provided in said radio communication apparatus and transmits and receives a radio signal, through a load impedance element when said first antenna is connected with the radio communication circuit, and so as to connect said first antenna to the ground of said housing through said load impedance element when said second antenna is connected with the radio communication circuit that transmits and receives the radio signal;
• and
• a controller for controlling an element value of said load impedance element so as to set a current flowing on said housing to be equal to or smaller than a predetermined value when said radio communication apparatus transmits the radio signal, thereby controlling a specific absorption rate (SAR) to be equal to or smaller than a predetermined value.

A radio communication apparatus comprising:

• a radio antenna apparatus including an antenna connected with a radio communication circuit that transmits and receives a radio signal;
• and
• a radio communication circuit, operatively connected with said antenna, for transmitting and receiving a radio signal,
• wherein said radio antenna apparatus comprises:
• a parasitic element;
• a load impedance element connected between said parasitic element and a ground of a housing of the radio communication apparatus including the radio communication circuit;
• and
• a controller for controlling an element value of said load impedance element so as to set a current flowing on said housing to be equal to or smaller than a predetermined value when said radio communication apparatus transmits the radio signal, thereby controlling a specific absorption rate (SAR) to be equal to or smaller than a predetermined value.

A radio communication apparatus comprising:

• a radio antenna apparatus including first and second antennas;
• and
• a radio communication circuit, operatively connected with either one of said first antenna and said second antenna, for transmitting and receiving a radio signal,
• wherein the radio antenna apparatus further comprises:
• a switch device for switching over so as to connect said second antenna to a ground of a housing of the radio communication apparatus including the radio communication circuit, that is provided in said radio communication apparatus and transmits and receives a radio signal, through a load impedance element when said first antenna is connected with the radio communication circuit, and so as to connect said first antenna to the ground of said housing through said load impedance element when said second antenna is connected with the radio communication circuit that transmits and receives the radio signal;
• and
• a controller for controlling an element value of said load impedance element so as to set a current flowing on said housing to be equal to or smaller than a predetermined value when said radio communication apparatus transmits the radio signal, thereby controlling a specific absorption rate (SAR) to be equal to or smaller than a predetermined value.