摘要:
An antenna assembly has a first helical antenna and a second rod antenna extending through inside said first antenna in the axis direction. When the antenna is retracted, the upper end of a conductive portion of the second antenna passes through the first antenna to be positioned below the lower end of the first antenna, and when the antenna is extended, the lower end portion of the conductive portion of the second antenna is electrically connected to the upper end portion of the first antenna. Therefore, the length of the second antenna can be reduced as compared with a length defined based on wavelengths of transmitted signals. Consequently, an antenna assembly which requires a smaller housing space can be obtained.
摘要:
An antenna unit in which fine antenna characteristic can be obtained when the antenna is contained/pulled out. When the second antenna (9) is contained, the second antenna is electrically disconnected from the feeding circuits (5, 7) by the antenna cover (13), so that only the first antenna (8) operates as antenna. On the other hand, when the second antenna is pulled out, the first antenna is compressed by the antenna stopper element (21) and the electrical length is varied, so that only the second antenna operates as antenna. As a result, fine antenna characteristic can be obtained when the antenna is contained/pulled out.
摘要:
An antenna unit operating for two frequency bands either when contained or pulled out. A fixed antenna unit 20 and a slide antenna unit 30 are provided. A helical antenna 21 is provided in the fixed antenna unit 20. A first monopole antenna 31 having the same axis as the helical antenna 21, a second monopole antenna 32, and an antenna cover 33 for holding the second monopole antenna 32 on the extended axis of the first monopole antenna 31 are provided in the slide antenna unit 30. The first monopole antenna 31 is held at the position where is not electromagnetically connected to the helical antenna 21 when the slide antenna unit 30 is pulled out, and the second monopole antenna 32 is held at the position where it is electromagnetically connected to the helical antenna 21. Further, the first monopole antenna 31 is held at the position where is electromagnetically connected to the helical antenna 21, and the second monopole antenna 32 is held at the position where is not electromagnetically connected to the helical antenna 21.
摘要:
An antenna apparatus for use in a portable cellular telephone that can avoid deterioration in signal radiation characteristics caused by the adverse influence of a user's head during the use of the telephone. Two sleeves have been fixed to a housing for a portable cellular telephone. A linear radiating conductor having a .lambda./4-electrical length is slidably supported by the housing by way of the two sleeves so that it can be both freely pulled out of or accommodated in the housing. The radiating conductor is extended at one end on the side of the power-feed point by a length equivalent to n.lambda./2. Also, a tubular conductor is coaxially disposed with the extended portion so as to form a power-feed coaxial line. When the radiating conductor is pulled out of the housing to such a degree as to reveal the coaxial line, the monopole antenna projects sufficiently away from a user's head, and a deterioration in signal radiation characteristics can thus be prevented.
摘要:
A portable telephone having an antenna for transmitting and/or receiving a wireless signal, a microphone for generating a sound signal corresponding to an input sound, a transmitting and receiving circuit for generating a wireless signal corresponding to the sound signal generated by the microphone to transmit the wireless signal through the antenna and generating a sound signal corresponding to the wireless signal received by the antenna, a receiver for outputting sound corresponding to the sound signal generated by the transmitting and receiving circuit, a shield case for surrounding and housing all or part of the transmitting and receiving circuit and being conductive, an electric wave absorber with one face in contact with a predetermined area of the shield case for absorbing an electric wave, and a conductive layer formed on another face of the electric wave absorber and electrically connected to the shield case.
摘要:
An antenna that functions as an approximately balanced antenna that is structurally asymmetric but electrically symmetric includes a first antenna element that is extendable and retractable, a second fixed antenna element, an unbalanced transmission line feeding the first and second antenna elements, and a balanced-unbalanced convertor. At a time of extending the first antenna element, the first and second antenna elements are supplied an electric power from the unbalanced transmission line through the balanced-unbalanced convertor, so that the first and second antenna elements cooperate to function as an antenna.
摘要:
A mono-pole antenna is composed of a first element and a second element. An insulator spacer is disposed between the first element and the second element so as to capacitively couple them. In the state that the antenna is retracted, the helical antenna operates. In the state that the antenna is extended, the mono-pole antenna composed of the first element and the second element operates. Since the mono-pole antenna is composed of the first element and the second element that are capacitively coupled, even if the electrical length of the helical antenna is different from the electrical length of the mono-pole antenna, the impedances can be properly matched with a common matching circuit.
摘要:
A direct-current circuit breaker includes a switching unit inserted in the direct-current line; and a commutation circuit that includes a series circuit including a first current-limiting element and an interrupting unit that forms a current zero point by superimposing a resonance current on a direct current flowing in the direct-current line and interrupts the direct current at the current zero point, that is connected in parallel with the switching unit, and that becomes a flow path for the direct current after the switching unit is opened, wherein current interruption is performed by the interrupting unit after the switching unit is opened.
摘要:
A direct-current circuit breaker includes a switching unit inserted in the direct-current line; and a commutation circuit that includes a series circuit including a first current-limiting element and an interrupting unit that forms a current zero point by superimposing a resonance current on a direct current flowing in the direct-current line and interrupts the direct current at the current zero point, that is connected in parallel with the switching unit, and that becomes a flow path for the direct current after the switching unit is opened, wherein current interruption is performed by the interrupting unit after the switching unit is opened.
摘要:
It is intended to provide a process for producing unstable amorphous benzimidazole compounds having a proton pump inhibitor function, and stable solid preparations for medicinal use containing these compounds which are produced by blending such an amorphous benzimidazole compound with a nontoxic base such as a basic inorganic salt, forming an intermediate coating layer on the layer containing the active ingredient and further forming an enteric coating layer or a release-controlling coating layer.