Abstract: It is an object of the present invention to provide a wireless communication system, which ensures that communication can be maintained in an excellent status although a mobile wireless station may be moved in a service area. A CPU (210) of a mobile wireless station (2) in process of transmission is operated to causes a receiving circuit (202) to periodically notify the CPU (210) of the electric field intensity of a received radio wave. When the electric field intensity of the received radio wave becomes lower than a predetermined value, the CPU (210) is operated to judge the distance from a base station (1), with which the mobile wireless station (2) is currently communicating, is increased, and the CPU (210) is operated to control the receiving circuit (202) to receive radio waves on transmission frequencies of base stations (1) other than the base station (1) and detect the electric field intensities of the received radio waves.

Abstract: A car detecting unit detects entrance of an incoming car into a drive-through store. A voice processing unit processes a voice signal from a first microphone of a menu board. A base station connected to the menu board via the voice processing unit transmits/receives wirelessly the voice signal and a control signal. A head set having a second microphone and an earphone is put on a head of a store clerk for use. Order taker equipment connected to the head set transmits/receives wirelessly the voice and control signals to/from the base station. Upon detection of the incoming car by the car detecting unit, operation of the voice processing unit is automatically started to generate the control signal corresponding to a level of the voice signal in the voice processing unit. Voice level in the base station and order taker equipment is automatically adjusted according to the control signal.

Abstract: A car detecting unit detects entrance of an incoming car into a drive-through store. A voice processing unit processes a voice signal from a first microphone of a menu board. A base station connected to the menu board via the voice processing unit transmits/receives wirelessly the voice signal and a control signal. A head set having a second microphone and an earphone is put on a head of a store clerk for use. Order taker equipment connected to the head set transmits/receives wirelessly the voice and control signals to/from the base station. Upon detection of the incoming car by the car detecting unit, operation of the voice processing unit is automatically started to generate the control signal corresponding to a level of the voice signal in the voice processing unit. Voice level in the base station and order taker equipment is automatically adjusted according to the control signal.