Abstract: It is an object of the present invention to suppress an abrupt gain change and smoothly and highly accurately control transmitted electric power even if the transmitted electric power greatly changes when a closed loop control that crosses the threshold value as the detection limit of the transmitted electric power. The transmitted electric power of a self-station is detected to obtain an error between the detected transmitted electric power of the self-station and transmitted electric power set in accordance with a transmitted electric power control bit sent to the self-station from the other station. A buffer unit such as a transmitted electric power deciding part, an error integrating part or the like is provided for preventing the obtained error from greatly changing upon great change of the transmitted electric power when the transmitted electric power is controlled by crossing the threshold value as the detection limit of the transmitted electric power.

Abstract: An antenna selection diversity apparatus capable of shortening, when antennas are switched in frame units, a measuring time of antennas and shortening the time of selecting an optimal antenna from among a plurality of antennas on standby. In this apparatus, an antenna selection section (109) selects one of three antennas as an antenna in actual use for a period of a plurality of frames consecutively according to selection priority stored in an antenna information storage section (108) and gives an instruction for selecting one of two antennas on standby as an antenna to be measured once at a period of a plurality of frames to an antenna selection switch (104).

Abstract: A determining section (18) and gain variation amount detecting section (9) detect a period having a possibility of a DC-component offset in an internal circuit of a direct conversion receiver increasing beyond an allowable value due to AGC operation, and during the period, a cut-off frequency of each of high-pass filters (12a to 12d) is set at a frequency higher than that in general operation, thereby rapidly converging transient responses of signals passed through the high-pass filters, while controlling precisely operation timings of reception power measuring section (16), gain calculating section (22), gain control section (23) and circuit power supply control section (24) composing an AGC loop, whereby the DC offset is prevented from increasing and stable circuit operation is assured. It is thereby possible to achieve further reductions in size and power consumption of a CDMA receiver using the direct conversion receiver.

Abstract: An antenna selection diversity apparatus capable of shortening, when antennas are switched in frame units, a measuring time of antennas and shortening the time of selecting an optimal antenna from among a plurality of antennas on standby. In this apparatus, an antenna selection section (109) selects one of three antennas as an antenna in actual use for a period of a plurality of frames consecutively according to selection priority stored in an antenna information storage section (108) and gives an instruction for selecting one of two antennas on standby as an antenna to be measured once at a period of a plurality of frames to an antenna selection switch (104).

Abstract: It is an object of the present invention to switch bands with a simple structure in which frequency bands can be individually switched respectively in a transmission and a reception and only a receiving part can be switched to another frequency band without disconnecting an upward line during communication. The device of the invention includes an antenna (1) capable of transmitting and receiving radio waves of first and second frequency bands, a wave separator (2), antenna sharing devices (3A, 3B) respectively provided so as to correspond to the frequency bands, transmitting circuits (4A, 4B), transmitting PLL synthesizers (5A, 5B), receiving circuits (6A, 6B) and receiving PLL synthesizers (7A, 7B).

Abstract: It is an object of the present invention to switch bands with a simple structure in which frequency bands can be individually switched respectively in a transmission and a reception and only a receiving part can be switched to another frequency band without disconnecting an upward line during communication. The device of the invention includes an antenna (1) capable of transmitting and receiving radio waves of first and second frequency bands, a wave separator (2), antenna sharing devices (3A, 3B) respectively provided so as to correspond to the frequency bands, transmitting circuits (4A, 4B), transmitting PLL synthesizers (5A, 5B), receiving circuits (6A, 6B) and receiving PLL synthesizers (7A, 7B).

Abstract: It is an object of the present invention to suppress an abrupt gain change and smoothly and highly accurately control transmitted electric power even if the transmitted electric power greatly changes when a closed loop control that crosses the threshold value as the detection limit of the transmitted electric power. The transmitted electric power of a self-station is detected to obtain an error between the detected transmitted electric power of the self-station and transmitted electric power set in accordance with a transmitted electric power control bit sent to the self-station from the other station. A buffer unit such as a transmitted electric power deciding part, an error integrating part or the like is provided for preventing the obtained error from greatly changing upon great change of the transmitted electric power when the transmitted electric power is controlled by crossing the threshold value as the detection limit of the transmitted electric power.

Abstract: At the time of ordinary communication, up-mixer 108 combines a signal with a frequency f2 from frequency synthesizer 124 with I and Q signals for transmission that are quadrature modulated in quadrature modulator 105, down-mixer 115 combines the signal with the frequency f2 with a received signal, then only in the case of receiving a signal with a frequency fr′ different from a frequency fr, frequency synthesizer 125 that generates a signal with a frequency f3 different from the frequency f2 is operated, and frequency synthesizer 125 and down-mixer 115 are connected with switch 127, so that down-mixer 115 combines the signal with the frequency f3 with a received signal. It is thereby possible to switch frequencies fast and with low current consumption in receiving a signal with a reception frequency other than a combination of transmission frequency and reception frequency specified in an ordinary radio system.

Abstract: A determining section (18) and gain variation amount detecting section (9) detect a period having a possibility of a DC-component offset in an internal circuit of a direct conversion receiver increasing beyond an allowable value due to AGC operation, and during the period, a cut-off frequency of each of high-pass filters (12a to 12d) is set at a frequency higher than that in general operation, thereby rapidly converging transient responses of signals passed through the high-pass filters, while controlling precisely operation timings of reception power measuring section (16), gain calculating section (22), gain control section (23) and circuit power supply control section (24) composing an AGC loop, whereby the DC offset is prevented from increasing and stable circuit operation is assured. It is thereby possible to achieve further reductions in size and power consumption of a CDMA receiver using the direct conversion receiver.

Abstract: To provide a power amplifier circuit with a smaller circuit scale and with good characteristics over a wide range of load impedance. A configuration includes: a DC/DC converter 2108 which delivers a supply voltage from a battery 2111 to a power amplifier 1302 according to control commands from a control circuit 2109; a directional coupler 2101 which outputs a signal from one terminal 2101a according to signal waves received by an antenna 1306 from a second matching circuit 105 and outputs a signal from another terminal 2101b according to reflected waves received from the antenna 1306; and detectors 2102 and 2103 or the like.

Abstract: A transmission electric power control device includes: a coupler 12, detector 13, electric power amplifier 14, error detection means 15, target value generation means 16, gain variable means 17, control calculation means 18, control calculation parameter generation means 19, modulator 20, control variable addition means 21, transmission electric power control means 22, and transmission electric power designation means 23. In this case, the automatic transmission electric power control feedback loop includes: the coupler 12, detector 13, error detection means 15, control calculation means 18, control calculation parameter generation means 19, transmission electric power designation means 23, control variable addition means 21 and gain variable means 17.

Abstract: To provide a power amplifier circuit with a smaller circuit scale and with good characteristics over a wide range of load impedance. A configuration includes: a DC/DC converter 2108 which delivers a supply voltage from a battery 2111 to a power amplifier 1302 according to control commands from a control circuit 2109; a directional coupler 2101 which outputs a signal from one terminal 2101a according to signal waves received by an antenna 1306 from a second matching circuit 105 and outputs a signal from another terminal 2101b according to reflected waves received from the antenna 1306; and detectors 2102 and 2103 or the like.

Abstract: A transmission power control in a wireless communication, in that based upon transmission power designation information “A” functioning as a power control target derived from a transmission power designating unit 16, a transmission power error “E” is detected from a difference between a detection value “D” of an outputted transmission signal and a power control target value “C”. This transmission power error “E” is multiplied by a loop gain “G” of a feedback loop set by a loop gain setting unit 22 so as to produce a feedback correction value “F”. The transmission power control is carried out based on the feedback correction value “F”.

Abstract: There is provided a radio communication apparatus and a radio communication method in which a transmission mixer and a reception mixer are shared in mobile communication systems each having a different frequency band without using frequency switching means for frequency synthesizers to make it possible to improve miniaturization of the apparatus. At the transmitting side, transmission IF values of f11 and f12 (f11=f12) are set to frequencies close to (ft1−ft2)/2, and a lower local configuration is formed in the first system and an upper local configuration is formed in the second system using the frequency lower than that of the first system. At the receiving side, values of f41 and f42 (f41=f42) are set to frequencies close to (fr1−fr2)/2, a lower local configuration is formed in the first system and an upper local configuration is formed in the second system using the frequency lower than that of the first system.

Abstract: A power amplifier has an input terminal; an output terminal; an N number of bypassable amplification circuits which are connected directly or indirectly in a sequential manner between the input terminal and the output terminal; an impedance conversion circuit which is connected directly or indirectly between the amplification circuit of a final stage and the output terminal; and a bias control circuit which controls the amplification circuits, each of the amplification circuits is configured by a high-frequency switch circuit, and an amplifier which is connected directly or indirectly to the switch circuit, and the bias control circuit controls power source voltages of the amplifiers and controls status of the switch circuit.

Abstract: In the radio equipment in which necessary absolute precision of the transmit power can be assured while keeping the power variable amount precision in transmit power adjustment and the transmit power control of wide dynamic range and high linearity also is requested.

Abstract: A transceiver circuit with a heterodyne receiver circuit is provided. Output signals of first and second local oscillator 103, 104 are mixed by a local frequency converter 105. An output signal of the converter 105 passes a filter 106 and inputs a modulator 111 of a transmitter circuit 101 as well as a first frequency converter 122 of a receiver circuit 102. The second local oscillator 104 comprises a frequency synthesizer whose output signal varies for a transmission or a receiving mode. The output signal of the second local oscillator 104 also inputs the second frequency converter 124 of the receiving mode. A reference frequency of the second local oscillator 104 is set higher than a frequency step between communication channels so that a quick switching of the frequency is performed. Thus, the transceiver circuit of this invention is suitable for a compact size and hardly generates unwanted spurious components at transmission mode.

Abstract: A metal complex compound having the formula: ##STR1## wherein each of X.sub.1 and X.sub.2 which may be the same or different, is a nitro group, a halogen atom, a phenylazo group (inclusive of a substituted phenylazo group) or a naphthylazo group (inclusive of a substituted naphthylazo group), each of n.sub.1 and n.sub.2 which may be the same or different, is an integer of from 1 to 3, each of R.sub.1 and R.sub.2 which may be the same or different, is an amino group, a monoalkylamino group, a dialkylamino group, an acetylamino group and a benzoylamino group (inclusive of a substituted benzoylamino group), M is a chromium atom, an iron atom, a cobalt atom, m is an integer of at least 2, and y.sup.m.sym. is a bivalent or higher polyvalent metal ion. The metal complexes are useful as near infrared absorbers.

Abstract: A handy image data filing apparatus is disclosed, which is made up of a hand scanner as an image data reading device and an IC memory card as an image data storing medium. Image data on an object such as a name card is read by the hand scanner, and filed into the IC memory card. The read data is stored into the IC memory card, together with ID data for identifying the image data to be stored. The ID data is used for retrieving the image data later, and is entered from a keyboard. For retrieval, ID data corresponding to the desired image data is entered from the keyboard. The image data is specified by the ID data entered, and displayed by a liquid crystal display device.

Abstract: This invention relates to a xanthene derivative that develops color on oxidation, so that it is favorably used for a photoresist, a PS plate or a proofing agent. The xanthene derivative, which has the following structural formula (I), is produced by putting a fluoran derivative represented by the following structural formula (II) to an esterification reaction and then to a reduction reaction. ##STR1## In the above formulae R.sub.1 and R.sub.2 independently stand for hydrogen, an alkyl radical with 1 to 8 carbon atoms, a tetrahydrofurfuryl radical, a substitued or an unsubstituted phenyl radical, a substituted or an unsubstituted benzyl radical or a cyclic alkyl radical; in addition, R.sub.1 and R.sub.2 are able to form a ring in pairs. R.sub.3 and R.sub.6 independently stand for hydrogen, chlorine, fluorine, a lower alkyl radical or a lower alkoxy radical. R.sub.4 and R.sub.