Abstract: A wireless device has a housing, a patch antenna, and an open/shut sensing unit which senses the open/shut state of the housing and forms an open/shut signal indicating the open/shut state. The patch antenna has a first element which corresponds to a first polarized wave, a second element which corresponds to a second polarized wave and is to be added to the first element, and a switching unit. The switching unit disconnects and connects the second element from and to the first element based on the open/shut signal to make the patch antenna suitable for the first or second polarized wave.

Abstract: A radio communication device that outputs an alarm when a reception level of a radio wave from a wireless unit is less than a threshold value, includes a reception level measuring section for measuring the reception level of the radio wave transmitted from the wireless unit at certain times. A threshold value setting section for setting a first threshold value or a second threshold value less than the first threshold value based on a difference between the reception level of the radio wave measured a previous time and the reception level of the radio wave measured a subsequent time. An alarm output requesting section for causing an alarm output section to output an alarm if the reception level of the radio wave measured a subsequent time is less than the first threshold value or the second threshold value.

Abstract: A wireless device has a housing, a patch antenna, and an open/shut sensing unit which senses the open/shut state of the housing and forms an open/shut signal indicating the open/shut state. The patch antenna has a first element which corresponds to a first polarized wave, a second element which corresponds to a second polarized wave and is to be added to the first element, and a switching unit. The switching unit disconnects and connects the second element from and to the first element based on the open/shut signal to make the patch antenna suitable for the first or second polarized wave.

Abstract: A folding type portable radio machine, includes a chassis part formed by a first chassis and a second chassis, the second chassis being foldably connected to the first chassis. The chassis part includes a conductive part having conductivity whose full length is an approximately half wave length (?/2) of a using frequency of the radio machine, and an electric notch.

Abstract: A folding type portable radio machine, includes a chassis part formed by a first chassis and a second chassis, the second chassis being foldably connected to the first chassis. The chassis part includes a conductive part having conductivity whose full length is an approximately half wave length (?/2) of a using frequency of the radio machine, and an electric notch.

Abstract: A folding type portable radio machine, includes a chassis part formed by a first chassis and a second chassis, the second chassis being foldably connected to the first chassis. The chassis part includes a conductive part having conductivity whose full length is an approximately half wave length (&lgr;/2) of a using frequency of the radio machine, and an electric notch.