Nec Corporation

Kabushiki Kaisha Toshiba

Yoshio Itagaki

Shinobu Kimata

Toshiki Seshita

Masayuki Sugiura

Yasuhiko Kuriyama

Yoshitomo Sagae

Yugo Kunishi

Kiyokazu Otsuka

Hirotsugu Wakimoto

Masanori Ochi

Toshiyuki Shimizu

Noriyasu Kurihara

A semiconductor switch includes a plurality of first terminals, a second terminal commonly provided for the plurality of first terminals, a plurality of first MIS switches provided between the plurality of the first terminals and the second terminal, respectively, configured to pass-through or cut-off a high frequency signal between the plurality of the first terminals and the second terminal, and formed on a SOI substrate, and a capacitor formed on the SOI substrate, connected between the second terminal and the plurality of the first MIS switches, and provided for the plurality of the first terminals commonly.

Semiconductor switch

According to one embodiment, a high-frequency switch includes a high-frequency switch IC chip. The high-frequency switch IC chip has a high-frequency switching circuit section including an input terminal, a plurality of switching elements, a plurality of high-frequency signal lines, and a plurality of output terminals. The input terminal is connected to each of the plurality of output terminals via each of the plurality of switching elements with the high-frequency signal lines having the same lengths. The plurality of output terminals are arranged on a surface at an outer periphery of the high-frequency switch IC chip. The input terminal is arranged on the surface of the high-frequency switch IC chip at the center of the high-frequency switch IC circuit section.

High-frequency switch

There is disclosed a private branch exchange in which an SIP terminal is capable of receiving great variety of services provided by the private branch exchange without upgrading version of software of the SIP terminal itself. A standard SIP protocol control module, an expanded SIP protocol a control module, and an expanded SIP protocol b control moduleare disposed for SIP system protocol corresponding terminals, convert signals (requests) from the SIP system protocol corresponding terminals into signals of a protocol inside an IP-PBXto transmit the signals to a PBX basic connection process providing module, and convert a signal (responses to the request, or a request to the SIP system protocol corresponding terminal) from the PBX basic connection process providing moduleinto a signal of an SIP system protocol to transmit the signal to the SIP system protocol corresponding terminal.

Network, private branch exchange, and multi protocol communication terminal control method for use in the exchange

A standard-SIP (session initiation protocol) protocol control module and an expanded sip protocol control module are provided so as to correspond to respective Sip protocol corresponding terminals, such as wireless LAN terminals compliant with the SIP. A signal (a request) from each Sip protocol corresponding terminal is converted into a signal according to a protocol of an IP-PBX and is sent to a PBX basic-connection-processing providing module. A signal (a response for the request or a request to the Sip protocol corresponding terminal) from the PBX basic-connection-processing providing module is converted into an Sip protocol signal and is sent to the Sip protocol corresponding terminal. A location-information management module collects a basic service set identifier (BSSID) from each wireless LAN network and stores the BSSID information into a database.

Network, private branch exchange, wireless LAN terminal, and multiprotocol communication terminal control method therefor

In a portable telephone system including a base station and a mobile station which communicate with each other by using one time divisional time slot including a high speed channel and a low speed channel, a first communication requiring the high speed channel by a first calling party from the base station to the mobile station and a second communication not requiring the high speed channel by a second party from the base station to the mobile station are carried out simultaneously by using the high speed channel and the low speed channel, respectively.

Portable telephone system capable of simultaneously carrying out high speed communication and low speed communication by one time slot and communication method therefor

In a PBX network, a global database is provided in each PBX node for storing shared data for verification of authorized mobile stations when accessing the network via a wireless cell-site station. During a wireless mode, a mobile station monitors the strength of its downlink signal from a first cell-site station of a first PBX node. If it falls below a threshold, the mobile station begins a scan across the spectrum. If a strong signal is detected, it stops the scan and transmits a handover request message to a second cell-site station transmitting that strong signal. The second node receives the message via the second cell-site station to establish the mobile's verification. If the mobile station is an authorized user, the second node transmits a handover grant message to the second cell-site station, transmits a command message to the first node for a switchover to a link between the first and second nodes, and connects the link to the second cell-site station.

Growing community of inventors

Tokyo, Japan

Yoshio Itagaki