摘要:
A feed-forward amplifier of a type preventing unwanted waves from being outputted in an initial operation suitable to a use in a radio transmitter-receiver in a radio communication system, aimed to reduce a loss in the course from an output of a main amplifier to an output of the apparatus by implementing an output control during the initial operation in the front stage of the main amplifier without switches having been heretofore used, further reducing a power consumption of the apparatus. The feed-forward amplifier of this invention is provided with a control unit which controls a pilot signal variably attenuating unit so as to gradually decrease an attenuation quantity of a pilot signal with use of results of detection conducted by a power source start-up detecting means and a main signal detecting means as timing information after a start-up of a power source of a main amplifier, and controls a main signal variably attenuating unit so as to gradually decrease an attenuation quantity of a main signal after the pilot signal variable attenuating unit has decreased the attenuation quantity of the pilot signal.
摘要:
A parallel operation system of transmission amplifiers enable the parallel running by the two distortion compensation amplifiers using the digital pre-distorter system and to provide a parallel operation system of the transmission amplifiers that makes it possible to switch to respective single running easily. The parallel operation system includes first and second transmission amplifiers which receive common input signals for outputting amplified signals from respective ones; and a coupling unit which combines outputs of the first and second transmission amplifiers, to provide as its output; the first and second transmission amplifiers each having a main amplifier; and a modulation unit disposed on the input side of the main amplifier; wherein the output of one of the modulation units included in the first and second transmission amplifiers is fed in common to the main amplifiers included in the first and second transmission amplifiers.
摘要:
The present invention relates to a feed-forward amplifying device suitable for radio communication systems such as digital automobile telephone. In the feed-forward amplifying device which includes a distortion extracting loop circuit unit including a main amplifier which amplifies a main signal in a main signal system, the distortion extracting loop circuit unit creating a distortion extracting signal by controlling the phase of the main signal the distortion extracting signal obtained by canceling the main signal component of an output from the main amplifier; and a distortion removing loop circuit unit arranged at the rear stage of the main amplifier, the distortion removing loop circuit unit producing only the main signal component from a signal in the main signal system at the rear stage of the main amplifier using the distortion extracting signal obtained by canceling the main signal component, the distortion extracting loop circuit unit executes phase control by shifting a phase control point where the main signal can be most canceled, thus creating the distortion extracting signal. This device can improve the power efficiency with a small back-up of the amplifier and stably produce a low-distortion amplified signal.
摘要:
A feedforward amplifier having a distortion detection loop and a distortion elimination loop is provided that achieves increased accuracy, improved response, and stable operation. A variable attenuator is placed in front of a detector in a loop output stage, and the amount of attenuation in the variable attenuator is set large during a transient response period during the rising of the amplifier, and set small during a steady-state condition. The detection of the transition to the steady-state condition is accomplished, for example, by comparing the detector output with a prescribed threshold value. The width of perturbation is set large during a transient response period, and set small during a steady-state condition.
摘要:
A lithium-ion secondary battery device comprises a positive electrode collector having a surface formed with a positive electrode active material layer containing a positive electrode active material; a negative electrode collector having a surface formed with a negative electrode active material layer containing a negative electrode active material; an electrically insulating porous separator; and an electrolyte containing a lithium salt and being in contact with the positive electrode active material layer, negative electrode active material layer, and separator. The negative electrode active material is a carbon material having a graphite structure. The amount of the carbon material supported by the negative electrode active material layer is 2.0 to 4.0 mg/cm2. The graphite structure in an X-ray diffraction pattern of the carbon material exhibits a peak intensity P101 of (101) plane and a peak intensity P100 of (100) plane having a ratio (P101/P100) of 2.0 to 2.8 therebetween.
摘要:
A polishing pad of excellent durability has a polishing layer is arranged on a base material layer, and the polishing layer comprises a thermosetting polyurethane foam having roughly spherical interconnected cells with an average cell diameter of 35 to 300 μm.
摘要:
A lithium secondary battery comprising positive and negative electrodes both capable of occluding and releasing lithium ions, and a lithium ion conductive material which contains a compound of formula (1) exhibits improved characteristics including charge/discharge efficiency, low-temperature properties and cycle performance when (a) only one substituent group of R1, R2, R3 and R4 in formula (1) is alkyl, (b) the negative electrode-constituting material partially contains a carboxyl or hydroxyl group-bearing compound, and the lithium ion conductive material contains propylene carbonate, or (c) a positive electrode active material is a lithium-containing transition metal compound, a negative electrode active material is a carbonaceous material, and the lithium ion conductive material contains as a non-aqueous electrolysis solution a solvent mixture of propylene carbonate and ethylene carbonate in combination with a chain-like carbonate as a low-viscosity solvent
摘要:
A method for inexpensively and easily manufacturing a polishing pad of excellent durability and polishing speed stability includes preparing a cell dispersed urethane composition by mechanical foaming, applying the cell dispersed urethane composition onto a base material layer, forming a polyurethane foamed layer having roughly spherical interconnected cells by curing the cell dispersed urethane composition, and regulating the thickness of the polyurethane foamed layer uniformly.
摘要:
A cathode, an anode and a porous film are first provided. Then, the cathode and anode are aligned with the porous film and a part of the cathode and a part of the anode are fixed to said porous film. Then, the cathode, anode and porous film are immersed in a liquid electrolyte. Finally, the cathode and anode are integrated with the porous film by compression. With this process, it is possible to produce a thin and lightweight polymer secondary battery or other secondary batteries with ease yet at low cost.
摘要:
The present invention provides a manufacturing method for an impeller with which molding and high-quality finishing can be performed extremely easily and quickly through resin molding using a die, and an impeller manufactured by the impeller manufacturing method. A metallic bush is disposed in a die, whereupon a resin material is injected through a gate in the die. A connecting portion between an unnecessary resin portion formed from residual resin material in the gate and a resin impeller main body molded around the bush is formed to be thin, and the unnecessary resin portion is removed from the impeller main body using pushing or withdrawing means.