Matsushita Electric Industrial Co., Ltd.

Matsushita Electric Ind., Ltd.

Mitsuhiro Suzuki

Seiji Horii

Akinori Tatsumi

Mikio Shimazu

Takako Hirose

Hiroaki Iwamoto

Takuya Kobayashi

Yukihiro Inoue

Takayuki Hamaki

Masahide Morozumi

Jun Yamaguchi

Minoru Morinaga

A drain diffusion layerincludes a low impurity concentration regionand a high impurity concentration region, and the low impurity concentration regionis located on the channel region side. An impurity layerhaving an opposite conductivity type to the drain diffusion layeris formed in the channel region, at a position away from the low impurity concentration regionby a distance T. Alternatively, the low impurity concentration regionand the impurity layerare located so as to contact each other. Still alternatively, a border impurity layer is provided between the low impurity concentration regionand the impurity layer. Thus, a semiconductor device including a high voltage transistor capable of suppressing the reduction of the electric current driving capability and performing stable driving, and a method for fabricating the same, can be provided.

Semiconductor device including a high voltage transistor

In a radio communication system for performing digital radio communications by using time-division multiplexed time slots, a first personal station receives its user's speech through the microphone, converts it into audio data, and transmits them on time slots to a second personal station. On the other hand, the first personal station receives non-audio data from the data processor connected with the second personal station and stores. When the audio data amount inputted to the first personal station in a unit time period is lower than a threshold and the communications between the first personal station and the second personal station are put in a silence condition, the first personal station transmits non-audio data on times slots to the second personal station. When the communications return to a sound condition, audio data transmission is restored. Whether each time slot carries audio data or non-audio data is designated by an identifier which is written in a predetermined field of each time slot.

Digital radio communication system with efficient audio and non-audio

The caller personal station of the present invention includes the following units: a channel search unit for scanning the plurality of communication channels to search for an unoccupied channel and regarding the unoccupied channel as a multicast channel; and a simultaneous call unit for repeatedly transmitting a simultaneous call frame on the multicast channel for a first predetermined time period, the simultaneous call frame indicating a simultaneous call to the other personal stations; a multicast unit for transmitting multicast frames on the multicast channel when a second predetermined time period has passed, the multicast frames containing data to be multicast. On receiving the simultaneous call frame by sequentially sensing the plurality of communication channels, the other personal stations enter a receiving state of multicast frames on the multicast channel. The simultaneous call unit includes the following units: a simultaneous call frame generation unit for generating the simultaneous call frame; a transmission timer for counting the first predetermined time period and generating a time-out; and a simultaneous call frame transmission unit for repeatedly transmitting the simultaneous call frame on the multicast channel from a start of counting the predetermined time period until the time-out is generated.

Caller personal station equipped with simultaneous call function and

Growing community of inventors

Moriguchi, Japan

Mitsuhiro Suzuki