Expanded communication method in cordless telephone system

A cordless telephone system comprising:

• a first base unit operatively coupled to a first telephone line;
• at least a second base unit operatively coupled to at least a second telephone line;
• a first portable unit, one of said first and at least second base units being a primary base unit for said first portable unit;
• and
• at least a second portable unit, one of said first and at least second base units not being a primary base unit for said first portable unit being a primary base unit for said at least second portable unit, said first and at least second portable units establishing calls with said primary units when the assigned primary unit is not in a busy state and establishing calls with another available base unit when the primary unit is in a busy state.

A communication method in a cordless telephone system having a base unit with which a plurality of portable units can be registered, and a portable unit registrable with a plurality of base units, comprising the steps of:

• sending a busy signal to all portable units registered with the base unit upon detection of a call request signal from the base unit;
• sending a busy signal to the other portable units except for a specific portable unit upon reception of a call request signal from the specific portable unit;
• sending a call termination signal to the other portable units except for the specific portable unit upon reception of a call termination signal from the specific portable unit;
• and
• performing a call.