Interterminal direct communication in digital mobile communication system

A mobile terminal which is capable of communicating with a second mobile terminal without intervention of a base station, the mobile terminal and the second mobile terminal being located within a service area of the base station in a digital mobile communication system having a predetermined number of channels, the mobile terminal comprising:

• a receiver;
• a transmitter;
• a power supply;
• detecting means for detecting an intermittent timing signal from a predetermined control channel of the base station;
• generating means for generating a transmitting timing signal and a receiving timing signal in synchronization with the intermittent timing signal;
• first control means for controlling the receiver and the transmitter such that the receiver intermittently receives signaling information from the second mobile terminal in accordance with the receiving timing signal and the transmitter intermittently transmit signaling information to the second terminal in accordance with the transmitting timing signal;
• and
• second control means for controlling the power supply such that power is intermittently supplied to the transmitter in accordance with the transmitting timing signal and is intermittently supplied to the receiver in accordance with the receiving timing signal.

A battery-saving method in a mobile terminal comprising a receiver, a transmitter and a battery, the mobile terminal being capable of communicating with a second mobile terminal without intervention of a base station, the mobile terminal and the second mobile terminal being located within a service area of the base station in a digital mobile communication system having a predetermined number of channels, the method comprising the steps of:

• detecting an intermittent timing signal from a predetermined control channel of the base station;
• generating a transmitting timing signal and a receiving timing signal in synchronization with the intermittent timing signal;
• controlling the receiver and the transmitter such that the receiver intermittently receives signaling information from the second mobile terminal in accordance with the receiving timing signal and the transmitter intermittently transmit signaling information to the second terminal in accordance with the transmitting timing signal;
• intermittently supplying power to the transmitter in accordance with the transmitting timing signal;
• and
• intermittently supplying power to the receiver in accordance with the receiving timing signal.