Abstract: In radio communication system that is able to transmit in two or more modulation modes, e.g., one modulation mode when phase shifts are performed and another modulation mode when phase shifts and amplitude shifts are performed, the disclosed invention can avoid that receiving band noise becomes so great not to conform to the GSM standards' prescription for such noise in a high voltage region of the power supply voltage, even when the output power is controlled by changing the amplitude of the input signal to the power amplifier circuitry while fixing the bias voltages to be applied to the power amplifying transistors. When the output power is controlled as above, in the modulation mode (GSM mode) when phase shifts are performed, idle currents flowing across the power amplifying transistors are regulated, depending on the power supply voltage, i.e., the idle currents are decreased when the power supply voltage is high and increased when the power supply voltage is low.

Abstract: An electronic part for a high frequency power amplifier is provided which is designed to constitute at least a part of a wireless communication system for performing feedback control by detecting an output power, and which can miniaturize a directional coupler. Also, the electronic part permits control of the output power with high accuracy without having any influence on a monitor voltage by a reflected wave propagating through a line of the directional coupler. The directional coupler includes a subline disposed in parallel to and in the vicinity of a part of a main line of an impedance matching circuit on the last output stage side of a power amplifier circuit, a capacitance element connected to between the main line and the subline, and a resistor element connected to between a constant potential point and a termination side of the subline.

Abstract: There are provided an electronic component for high frequency power amplification provided with a high-sensitivity output power detection circuit which is immune to the influence of changes in the use environment thereof, free of an output mismatch, small in size, and low in insertion loss and a wireless communication system using the electronic component.

Abstract: A directional coupler for detecting an output of a high frequency circuit module includes a main line and a sub-line overlapped with the main line with a dielectric material. The sub-line is set, in width, narrower than the main line and both side edges of the sub-line are allocated at the internal side of both side edges of the main line. Accordingly, the sub-line is surely provided opposed to the main line in the total width area and a signal current flowing into the main line can be detected in higher accuracy. Therefore, a wireless communication system for controlling an output of the high frequency circuit module by including such directional coupler assures stable communication.

Abstract: A high-frequency power amplification electronic part is disclosed which comprises a power amplifier circuit and a bias control circuit, the power amplifier circuit having a plurality of amplifier stages for amplifying an input high-frequency signal, the bias control circuit acting to bias the power amplifier circuit. The power amplifier circuit controls output power in accordance with input power that is varied while a gain of the power amplifier circuit is being fixed by either a bias current or a bias voltage supplied from the bias control circuit.

Abstract: A high-frequency power amplification electronic part is disclosed which comprises a power amplifier circuit and a bias control circuit, the power amplifier circuit having a plurality of amplifier stages for amplifying an input high-frequency signal, the bias control circuit acting to bias the power amplifier circuit. The power amplifier circuit controls output power in accordance with input power that is varied while a gain of the power amplifier circuit is being fixed by either a bias current or a bias voltage supplied from the bias control circuit.

Abstract: The present invention provides a high frequency amplifier using a power supply voltage regulate circuit for the purpose of compensating for variations in power supply voltage. The high frequency amplifier comprises three-stage power amplifiers which amplify an input signal and output the amplified signal, a bias circuit which supplies bias voltages for controlling these power amplifiers, a regulate circuit which compensates for variations in noise or gain with respect to the variations in the power supply voltage for driving the power amplifiers, etc. The regulate circuit holds constant an output voltage Vddc with respect to variations in power supply voltage Vdd and outputs the constant-held output voltage Vddc as a power supply voltage for the power amplifiers.

Abstract: In radio communication system that is able to transmit in two or more modulation modes, e.g., one modulation mode when phase shifts are performed and another modulation mode when phase shifts and amplitude shifts are performed, the disclosed invention can avoid that receiving band noise becomes so great not to conform to the GSM standards' prescription for such noise in a high voltage region of the power supply voltage, even when the output power is controlled by changing the amplitude of the input signal to the power amplifier circuitry while fixing the bias voltages to be applied to the power amplifying transistors. When the output power is controlled as above, in the modulation mode (GSM mode) when phase shifts are performed, idle currents flowing across the power amplifying transistors are regulated, depending on the power supply voltage, i.e., the idle currents are decreased when the power supply voltage is high and increased when the power supply voltage is low.

Abstract: There are provided an electronic component for high frequency power amplification provided with a high-sensitivity output power detection circuit which is immune to the influence of changes in the use environment thereof, free of an output mismatch, small in size, and low in insertion loss and a wireless communication system using the electronic component.

Abstract: A high-frequency power amplification electronic part is disclosed which comprises a power amplifier circuit and a bias control circuit, the power amplifier circuit having a plurality of amplifier stages for amplifying an input high-frequency signal, the bias control circuit acting to bias the power amplifier circuit. The power amplifier circuit controls output power in accordance with input power that is varied while a gain of the power amplifier circuit is being fixed by either a bias current or a bias voltage supplied from the bias control circuit.

Abstract: The present invention provides a high frequency amplifier using a power supply voltage regulate circuit for the purpose of compensating for variations in power supply voltage. The high frequency amplifier comprises three-stage power amplifiers which amplify an input signal and output the amplified signal, a bias circuit which supplies bias voltages for controlling these power amplifiers, a regulate circuit which compensates for variations in noise or gain with respect to the variations in the power supply voltage for driving the power amplifiers, etc. The regulate circuit holds constant an output voltage Vddc with respect to variations in power supply voltage Vdd and outputs the constant-held output voltage Vddc as a power supply voltage for the power amplifiers.

Abstract: A directional coupler for detecting an output of a high frequency circuit module includes a main line and a sub-line overlapped with the main line with a dielectric material. The sub-line is set, in width, narrower than the main line and both side edges of the sub-line are allocated at the internal side of both side edges of the main line. Accordingly, the sub-line is surely provided opposed to the main line in the total width area and a signal current flowing into the main line can be detected in higher accuracy. Therefore, a wireless communication system for controlling an output of the high frequency circuit module by including such directional coupler assures stable communication.

Abstract: A directional coupler for detecting an output of a high frequency circuit module includes a main line and a sub-line overlapped with the main line with a dielectric material. The sub-line is set, in width, narrower than the main line and both side edges of the sub-line are allocated at the internal side of both side edges of the main line. Accordingly, the sub-line is surely provided opposed to the main line in the total width area and a signal current flowing into the main line can be detected in higher accuracy. Therefore, a wireless communication system for controlling an output of the high frequency circuit module by including such directional coupler assures stable communication.

Abstract: A directional coupler for detecting an output of a high frequency circuit module includes a main line and a sub-line overlapped with the main line each other with a dielectric material. The sub-line is set, in the width, narrower than the main line and both side edges of the sub-line are allocated at the internal side of both side edges of the main line. Accordingly, the sub-line is surely provided opposed to the main line in the total width area and a signal current flowing into the main line can be detected in higher accuracy. Therefore, a wireless communication system for controlling an output of the high frequency circuit module by comprising such directional coupler assures stable communication.

Abstract: A lubricating oil composition containing as essential ingredients a lubricating oil component having a melting point of not higher than 100.degree. C., and one or more water-soluble dispersants selected from the group consisting of anionic polymeric dispersants of a molecular weight of 250 to 25,000, and polyoxyethylene type surfactants of a molecular weight of 3,000 to 20,000 and an HLB value of at least 18, said lubricating oil component being present in a stably dispersed state in water, achieves excellent adhesion when supplied to a machined portion.

Abstract: A lubricating oil composition containing as essential ingredients a lubricating oil component having a melting point of not higher than 100.degree. C., and one or more water-soluble dispersants selected from the group consisting of anionic polymeric dispersants of a molecular weight of 250 to 25,000, and polyoxyethylene type surfactants of a molecular weight of 3,000 to 20,000 and an HLB value of at least 18, said lubricating oil component being present in a stably dispersed state in water, achieves excellent adhesion when supplied to a machined portion.

Abstract: A lubricating oil composition containing as essential ingredients a lubricating oil component having a melting point of not higher than 100.degree. C., and one or more water-soluble dispersants selected from the group consisting of anionic polymeric dispersants of a molecular weight of 250 to 25,000, and polyoxyethylene type surfactants of a molecular weight of 3,000 to 20,000 and an HLB value of at least 18, said lubricating oil component being present in a stably dispersed state in water, achieves excellent adhesion when supplied to a machined portion.

Abstract: The present invention provides a glasslike carbon composite material which has reduced surface friction and excellent wear resistance and durability, because of the addition of specific ultrafine ceramic particles as a reinforcing material to a main component of glasslike carbon. The present invention further provides a method for preparing such a glasslike carbon composite material, as well as a method for preparing a glasslike carbon material.

Abstract: An electroplated composite coating of the invention which comprises 70 to 99.9 percent by weight of zinc or an alloy of zinc and 0.

Abstract: A cold-rolling lube oil for metallic materials is composed of (a) 40-90 wt. % of a monoester of a specific aliphatic carboxylic acid and a particular aliphatic alcohol, (b) 0.5-10 wt. % of at least one of dimer acids and polymer acids of certain unsaturated higher fatty acids, (c) 10-25 wt. % of a fats and fatty oils, or 5-70 wt. % of an ester obtained by reacting remaining carboxyl or hydroxyl groups of a specific polyester with a specific alcohol or fatty acid, (d) 0.3-10 wt. % of a phenol-type antioxidant, and (e) 0.3-10 wt. % of a sulfur-type antioxidant.