Communication terminal and control method

A communication terminal comprising:

• a Push to Talk call processing section which carries out Push to Talk calling according to a Push to Talk method;
• an Internet Protocol telephone processing section which carries out Internet Protocol telephone calling according to Session Initiation Protocol via an Internet Protocol network;
• a call control section which controls (a) Push to Talk calling via the Push to Talk call processing section and (b) calling via the Internet Protocol telephone processing section;
• a main body including a main body-side speaker and a main body-side microphone each of which carries out input and output of a voice in calling via the Push to Talk call processing section;
• a handset including a handset-side speaker and a handset-side microphone each of which carries out input and output of a voice in calling via the Internet Protocol telephone processing section;
• a main body-side codec which decodes an output signal from the call control section and outputs the decoded output signal to the main body-side speaker and which encodes an input signal from the main body-side microphone and inputs the encoded input signal to the call control section;
• and
• a handset-side codec which decodes an output signal from the call control section and outputs the decoded output signal to the handset-side speaker and which encodes an input signal from the handset-side microphone and inputs the encoded input signal to the call control section;
• wherein the main body is provided with a Push to Talk button for starting speech in the Push to Talk method;
• wherein, even in a case where the Push to Talk button is pressed by a user while calling via the Internet Protocol telephone processing section utilizing the handset-side speaker and the handset-side microphone, the Push to Talk call processing section does not output, as speech in calling via the Push to Talk call processing section, a voice input from the main body-side microphone.

A method for controlling a communication terminal that includes:

• a Push to Talk call processing section which carries out Push to Talk calling according to a Push to Talk method;
• an Internet Protocol telephone processing section which carries out Internet Protocol telephone calling according to Session Initiation Protocol via an Internet Protocol network;
• a call control section which controls (a) Push to Talk calling via the Push to Talk call processing section and (b) calling via the Internet Protocol telephone processing section;
• a main body including a main body-side speaker and a main body-side microphone each of which carries out calling via the Push to Talk call processing section, the main body being provided with a Push to Talk button for starting speech in the Push to Talk method;
• a handset including a handset-side speaker and a handset-side microphone each of which carries out calling via the Internet Protocol telephone processing section, the method comprising the steps of:
• decoding an output signal from the call control section and outputting the decoded output signal to the main body-side speaker;
• encoding an input signal from the main body-side microphone and inputting the encoded input signal to the call control section;
• decoding an output signal from the call control section and outputting the decoded output signal to the handset-side speaker;
• and
• encoding an input signal from the handset-side microphone and inputting the encoded input signal to the call control section;
• muting, by the Internet Protocol processing section, voice input from the handset-side microphone for a period in which the Push to Talk button is pressed in a case where the Push to Talk button is pressed by a user while calling via the Internet Protocol telephone processing section utilizing the handset-side speaker and the handset-side microphone.