Abstract: A liquid ejection apparatus includes a nozzle, a pressure chamber, a piezoelectric element, a count processing portion, and a detection processing portion. The nozzle ejects a liquid. The pressure chamber communicates with the nozzle and contains the liquid. The piezoelectric element changes a pressure in the pressure chamber in response to an input of a drive signal. The count processing portion counts a number of times that an electric signal output from the piezoelectric element and corresponding to vibration generated in the pressure chamber in response to the input of the drive signal to the piezoelectric element exceeds a predetermined threshold value. The detection processing portion detects a viscosity of the liquid contained in the pressure chamber, based on a count result of the count processing portion.

Abstract: A liquid ejection apparatus includes a nozzle, a pressure chamber, a piezoelectric element, an acquisition processing portion, and a restriction processing portion. The nozzle ejects a liquid. The pressure chamber communicates with the nozzle and contains the liquid. The piezoelectric element changes a pressure in the pressure chamber in response to an input of a drive signal. When image formation processing for ejecting the liquid from the nozzle is executed based on image data, the acquisition processing portion acquires a length of a non-ejection period in which the liquid is not ejected from the nozzle, the non-ejection period being included in an execution period of the image formation processing. When the length of the non-ejection period acquired by the acquisition processing portion is less than a predetermined first threshold value, the restriction processing portion restricts abnormality detection processing for detecting an abnormality of the nozzle using the piezoelectric element.

Abstract: A liquid ejection apparatus includes a nozzle, a pressure chamber, a piezoelectric element, an output processing portion, and a determination processing portion. The nozzle ejects a liquid. The pressure chamber communicates with the nozzle and contains the liquid. The piezoelectric element changes a pressure in the pressure chamber in response to an input of a drive signal. The output processing portion causes the piezoelectric element to output a first electric signal corresponding to vibration generated in the pressure chamber in response to the input of the drive signal to the piezoelectric element. The determination processing portion determines whether or not the pressure chamber is in a filled state in which the pressure chamber is filled with the liquid, based on a frequency of the first electric signal output by the output processing portion.

Abstract: A signal generation device includes a first signal generation portion and a second signal generation portion. The first signal generation portion, based on a reference signal that includes a plurality of rectangular single-wave signals, generates an original common signal in which the rise times of the two or more of the single-wave signals are extended so that they are different from each other, and the fall timing of one or more of the single-wave signals is shifted. The second signal generating portion generates a drive signal to be input to a piezoelectric element by extracting a rising edge of any one of the single-wave signals, the rise time of which is extended, from the original common signal amplified by the amplifying portion, maintaining a signal level changed by extracting the rising edge of the single-wave signal, and extracting a falling edge of a single-wave signal after the single-wave signal.

Abstract: Problems The present invention relates to a distance measuring device that measures the distance between a single signal transmitting means and a single signal receiving means with high accuracy by the signal transmitting means transmitting radio frequency signals. Means for Solving the Problems A distance measuring device is comprised of a signal transmitting means (101), a signal receiving means (102) and a signal processing means (103). The signal transmitting means transmits radio frequency signals, the components of which are a plurality of measuring signals in synchronization with an output reference signal of a reference oscillator (7).

Abstract: A radio relay system including a water-proof conductor housing on which is located a pair of antennas, one antenna being used for transmitting and receiving radio carrier wave signals of a first and a second frequency, respectively, while the other antenna is used for transmitting and receiving radio carrier wave signals of a third and a fourth frequency, respectively. A skirt for each of the antennas is located adjacent the antennas on the housing, one skirt has a length equal to a quarter of the wavelength of the first frequency while the other skirt has a length equal to a quarter wavelength of the third frequency.

Abstract: A radio relay system which comprising an external conductor, a first antenna installed on the externals conductor for transmitting and receiving a first radio carrier wave, a second antenna installed on the external conductor for transmitting and receiving a second radio carrier wave, a skirt provided around the second antenna, the skirt having a length equal to a quarter of the wavelength of the second radio carrier signal, and a relay device which includes a branching filter for extracting a part of the second radio carrier wave as a carrier wave, an adjusting unit for adjusting the amplitude and phase of the carrier wave extracted by the branching filter, and a combining unit for combining the carrier wave extracted by the branching filter with the second radio carrier wave received through the first antenna, and the relay device transmitting as the second radio carrier through the second antenna the first radio carrier wave received through the first antenna.

Abstract: A base station for a mobile communications system including an antenna for transmitting a radio carrier wave to a mobile communications device and receiving signals therefrom, a coaxial external conductor including a skirt in the form of a sun shade having a length equal to a quarter wavelength of the radio carrier wave, a radio section located inside the coaxial external conductor for providing radio communication with the mobile communication device via the antenna, and a connecting section connecting the radio section to a telephone line and where the antenna is configured in the form of an upper disk of a discone antenna and where the skirt is a lower conical member of the discone antenna.

Abstract: A method and apparatus for a hand-off of a call-in-progress according to the present invention is arranged such that both a first ratio of a length of time, in which a measured value of SNR is below a predetermined "threshold" to a total length of the measuring time, and a second ratio of a length of time, in which a measured value of RSSI is below a predetermined "threshold", to a total length of the measuring time are detected and that the first ratio functions mainly when the "threshold" of RSSI is predetermined to a relatively low value; and the second ratio functions mainly when the "threshold" of RSSI is predetermined to a relatively high value, thereby optimizing the hand-off timing.

Abstract: A pocket transceiver can be, for example a portable wireless telephone apparatus small enough to be put into a pocket of a user. The apparatus operates at a low power level. The pocket transceiver as an independent unit only handles signals at a low power level and is suitable for communication over close range. The pocket transceiver can also be used as a telephone apparatus for communication over long range, such as a mobile transceiver in a vehicle, by being connected to an adapter, which includes a power amplifier and a power controller for selecting an output power level out of multiple levels in response to an instruction from a transmitting-receiving unit of the pocket transceiver.

Abstract: A high-frequency signal booster which has at least one channel unit including a down-converter for converting input signals into intermediate-frequency signals and an up-converter for converting time into output signals. The respective up- and down-converters are separately equipped with station-originating signal oscillators. Further, the station-originating signal oscillator provided for the up-converter has a function of effecting the modulation with out-of-voice-band signals.

Abstract: In a mobile radio telephone system having multiple base stations controlled by a single line control unit, all base stations use a single common control channel in addition to their voice channels to communicate with a mobile station. If a calling signal from a mobile station is received by two or more base stations at once on the common control channel, the base station with the highest received signal level is selected. If voice signal quality becomes degraded during a call, the call is handed off to the base station with the highest received signal level.

Abstract: For use in a cellular radio-telephone system to enhance a signal from a cell site in an area shadowed by an obstruction such as a building or a mountain or the like, and to receive signals from subscribers in such areas, a cell enhancer includes bidirectional receivers, transmitters and amplifiers, the receivers and transmitters both including duplexer circuits for coupling signals in the proper up-link and down-link bands to the proper up-link and down-link antennas for transmission. Two embodiments of amplifiers are disclosed. A wideband amplifier network includes an input duplexer, a wideband amplifier with an attenuator, and an output duplexer, the duplexers coupling signals from both the up-link and down-link duplexer circuits to the amplifier for amplification. A narrow band network includes a plurality of amplifier modules each of which amplify only on one up-link and down-link channel assigned to the cell.

Abstract: A cell enhancer for use by one cellular provider in a cellular radio-telephone system includes a wideband amplifier for amplifying both down-link and up-link signals and a filter system for ensuring that signals outside of the cellular bands are not amplified. The filter system includes a wideband filter that passes at least the voice channels assigned to the cellular provider in the cell and a narrow band filter that passes the paging/access control channel in the cell. By using the filter system, signals outside the band assigned to the cellular provider, and particularly signals in the band assigned to the other cellular provider which may be present in the area, will not be amplified by the cell enhancer.

Abstract: A mobile radio communication system has base stations 1a, 1b, 1c at the centers of major service areas A, B, C defined by a contiguous array of hexagons or partially overlapping circles, and repeater or one way relay stations 3a-3m at each vertex or intersection point. The repeater stations have directional receiving antennas subtending successive 120.degree. arcs of surrounding minor service areas similarly defined by a ring array of hexagons or circles, amplifiers for imparting a high gain to signals received from mobile units in the minor service areas, and narrow width transmitting antennas for relaying the amplified signals to the base station closest each mobile unit. Such an arrangement enables a substantial reduction in the transmitter output capacity of the mobile units.

Abstract: A high dielectric constant element suitable for making a coaxial line shape resonator comprises a number of sheets, for instance, of mica or plastic, each having plural pieces of conductive film or electrodes provided on one face with appropriate small gaps inbetween, the sheets being assembled in a pile to form a high dielectric constant element body that has high equivalent .epsilon. value without using a conventional high dielectric constant ceramic body. Fine adjustment of the resonance frequency of the coaxial line shape resonator is easily made by adjusting number of sheets per length.

Abstract: A method and apparatus for a hand-off of a call-in-progress according to the present invention is arranged such that both a first ratio of a length of time, in which a measured value of SNR is below a predetermined “threshold” to a total length of the measuring time, and a second ratio of a length of time, in which a measured value of RSSI is below a predetermined “threshold”, to a total length of the measuring time are detected and that the first ratio functions mainly when the “threshold” of RSSI is predetermined to a relatively low value; and the second ratio functions mainly when the “threshold” of RSSI is predetermined to a relatively high value, thereby optimizing the hand-off timing.