Abstract: A drive control method for a micro machine device is provided. The micro machine device is made up of first and second electrodes opposed to each other and a dielectric layer disposed between them. The drive control method includes the steps of applying a control voltage between the first and the second electrodes so that an electrostatic force is exerted on the first and the second electrodes for displacing the first or the second electrode, and switching polarity of the control voltage at a predetermined period or a shorter period.

Abstract: A radio communication system includes multiple communications nodes which may become diversity branches, a relaying apparatus for relaying a communications signal, and a radio terminal which is able to use an IP address associated with a home address to move between wireless zones which the communications nodes form. The relaying apparatus includes a transmitting unit that transmits a received communications signal destined for the IP address, based on an instruction signal generated in response to a request of the radio terminal for site diversity, to at least two communications nodes including a communications node indicated in the instruction signal. The at least two communications nodes include a transmitting unit that transmits the communications signal to the radio terminal, and the radio terminal includes a receiving unit that receives the communications signal from each communications node.

Abstract: A delay detection circuit, including: a conversion circuit which converts time-domain signal into frequency-domain signal or which converts frequency-domain signal into time-domain signal, wherein the conversion circuit is used in a signal processing circuit which performs signal processing by quadrature modulation for a transmission signal, and the conversion circuit outputs a delay amount of a first signal with respect to the transmission signal.

Abstract: A system and apparatus including a mobile station for use in a spread communication system having a spread signal on a particular channel for establishing synchronization. The particular channel for establishing synchronization existing on a plurality of frequencies. The mobile station includes a receiving unit receiving the plurality of frequencies; a measuring unit measuring a strength or a correlation value of the spread signal of the particular channel for each of the plurality of frequencies received by said receiving unit; and a synchronization establishing unit establishing synchronization based on the measured strength or correlation value of the spread signal.

Abstract: A drive control method for a micro machine device is provided. The micro machine device is made up of first and second electrodes opposed to each other and a dielectric layer disposed between them. The drive control method includes the steps of applying a control voltage between the first and the second electrodes so that an electrostatic force is exerted on the first and the second electrodes for displacing the first or the second electrode, and switching polarity of the control voltage at a predetermined period or a shorter period.

Abstract: A search circuit in a CDMA system which has a plurality of base stations respectively employing different carrier frequencies, the search circuit selects one carrier frequency among the different carrier frequencies to perform a cell search of the one carrier frequency. The search circuit includes a first search unit searching a plurality of carrier frequencies of the DS-CDMA system; and a controller selecting a highest strength or highest correlation value carrier frequency among the plurality of carrier frequencies based on a result of the first search unit, setting the selected carrier frequency as the one carrier frequency among the different carrier frequencies to perform the cell search of the one carrier frequency. A mobile station adopting the search circuit includes a three-stage cell search process.

Abstract: A mobile communication system for transmitting broadcast data or multicast data includes a plurality of base stations forming a multicast or broadcast zone, the plurality of base stations transmitting a same multicast or broadcast data. Each of the plurality of base stations includes a first controller for determining a base station among a plurality of base stations; and a second controller for performing the transmission of the broadcast data or multicast data in accordance with the determined result.

Abstract: A mobile communication method for transmitting broadcast data or multicast data from a base station forming a multicast or broadcast zone in a mobile communication system by determining a base station among a plurality of base stations and performing the transmission of the broadcast data or the multicast data from a plurality of base stations in accordance with the determined result.

Abstract: A method of transmitting broadcast data or multicast data in a mobile communication system includes forming a multicast or broadcast zone by selecting a plurality of base stations, the plurality of base stations transmitting a same multicast or broadcast data, and at each of the plurality of base stations determining whether the broadcast data or multicast data is transmitted from a plurality of base stations and performing the transmission of the broadcast data or the multicast data in accordance with the determined result.

Abstract: A mobile communication system for transmitting broadcast data or multicast data including a plurality of base stations forming a multicast zone, which is included in a service area of the mobile communications system, the plurality of base stations transmitting a same multicast or broadcast data. Each of the plurality of base stations includes means for performing at a base station a transmission of multicast or broadcast data based on a determined result.

Abstract: A method of transmitting a multicast or broadcast data from a plurality of base stations forming a multicast zone, which is included in a service area of a mobile communications system includes performing at a base station among a plurality of base stations a transmission of multicast or broadcast data based on a determined result.

Abstract: A mobile communication system for transmitting broadcast data or multicast data from a base station forming a multicast or broadcast zone includes a first controller for determining a base station among a plurality of base stations and a second controller for performing the transmission of the broadcast data or the multicast data from the base station in accordance with the determined result.

Abstract: A system including base stations and a mobile station that performs a three-stage cell search process. Each base station includes a transmission unit using at least one carrier frequency for transmitting a perch channel signal, in which the at least one carrier frequency is uniquely distinguishable from carrier frequencies used by other base stations. The mobile station performs a first-stage search of the three-stage cell search and represents a search of a plurality of carrier frequencies; performs a second-stage search of the three-stage cell search and represents a search of a specified carrier frequency; performs a third-stage search of the three-stage cell search and represents a search of said specified carrier frequency; and includes a controller selecting the highest strength or highest correlation value carrier frequency among the carrier plurality of carrier frequencies based on a result of the first-stage search to set the selected carrier frequency as said specified carrier frequency.

Abstract: There is provided a radio interrogator system which reduces the interference with a radio transponder and avoids the decrease in throughput of the entire system in a case in which a plurality of radio interrogators are disposed at positions brought relatively close to each other and are simultaneously placed into operation. The plurality of radio interrogators are classified into two groups and each of the radio interrogators has an operation mode setting unit capable of exclusively setting, for each of the classified groups, a transmission mode for transmitting a radio transmission signal to a radio transponder or a reception mode for receiving a radio response signal transmitted from the radio transponder as a response to a radio transmission signal from the radio interrogator.

Abstract: Disclosed in a reading apparatus for supplying power to at least one of a plurality of superimposed RF tags and reading information from the tag while power is being supplied thereto. The apparatus includes means for generating high-frequency signals; electromagnetic wave generating means to which the high-frequency signals are input for generating electromagnetic waves from a plurality of locations, e.g., from both sides of the superimposed tags, by the high-frequency signals and causing the electromagnetic waves to interfere with each other on the tags; means for controlling the phase difference between the high-frequency signals, which are supplied to the electromagnetic wave generating means provided on both sides of the tags, in accordance with the position of a tag from which information is read; and phase shifting means for controlling the phase of at least one high-frequency signal so to produce the phase difference.

Abstract: Disclosed is a mobile radio communication system in which a position registration area number is reported from a base station to a mobile station within a radio zone, position information indicating a position registration area in which a mobile station resides is registered in storage means based upon position registration information that has been transmitted from the mobile station, and when there is an incoming call to a mobile station, a paging call is placed from a plurality of base stations within the position registration area, in which the base station resides, based upon position information that has been read out of the memory means. Updating of the position registration area of a mobile station can be performed automatically on the network side without the mobile station transmitting position registration information to the network side.

Abstract: The object of a radio terminal equipment is to achieve a highly accurate channel control and a favorable transmission quality. In order to achieve the object, in the radio terminal equipment, a channel controlling means is given in advance a period which accordingly makes both the processing and processing to be done to a transmission wave(s) by a radio station connected through a radio transmission line have lengths of time needed for the processes suitable for channel controlling and which is also suitable for a transmission system in a radio transmission line, and makes a radio wave received by a receiving means during the period the object of the processing. Therefore, a radio transmission system having the present invention applied adapts flexibly to various multiple access systems and modulation systems, and stably maintains the transmission quality of channels high, without having drastic restrictions on the configuration.

Abstract: A system establishes synchronicity of transmission and receiving for each reader/writer of an RF tag independently without obtaining synchronization of the reader/writers by means of an unspecified number of control terminals is desired as a reader/writer system. A reader/writer comprises a transmitter operable to transmit an interrogation signal to an RF tag, and a receiver operable to receive a response signal from an RF tag, wherein the transmitter is operable to transmit an interrogation signal based on a synchronization signal received from another reader/writer.

Abstract: A search circuit in a CDMA system which has a plurality of base stations respectively employing different carrier frequencies, the search circuit selects one carrier frequency among the different carrier frequencies to perform a cell search of the one carrier frequency. The search circuit includes a first search unit searching a plurality of carrier frequencies of the DS-CDMA system; and a controller selecting a highest strength or highest correlation value carrier frequency among the plurality of carrier frequencies based on a result of the first search unit, setting the selected carrier frequency as the one carrier frequency among the different carrier frequencies to perform the cell search of the one carrier frequency. A mobile station adopting the search circuit includes a three-stage cell search process.

Abstract: A system including base stations and a mobile station that performs a three-stage cell search process. Each base station includes a transmission unit using at least one carrier frequency for transmitting a perch channel signal, in which the at least one carrier frequency is uniquely distinguishable from carrier frequencies used by other base stations. The mobile station performs a first-stage search of the three-stage cell search and represents a search of a plurality of carrier frequencies; performs a second-stage search of the three-stage cell search and represents a search of a specified carrier frequency; performs a third-stage search of the three-stage cell search and represents a search of said specified carrier frequency; and includes a controller selecting the highest strength or highest correlation value carrier frequency among the carrier plurality of carrier frequencies based on a result of the first-stage search to set the selected carrier frequency as said specified carrier frequency.