摘要:
Although conventional antennas have characteristics suitable for mobile radio base stations, their vertical dimension is large, and locations of their installation are limited. A radiator for an first upper antenna 32 is arranged in a hollow nonconductive radome 2, using an internal conductor 7a and a metal pipe 10. A radiator for a second lower antenna 34 is arranged in the radome 2, using metal pipes 14 and 15. Two parasitic elements 31 are installed substantially in parallel with the first antenna 32 below a feeding point 9. Two parasitic elements 33 are installed substantially in parallel with the second antenna 34 above a feeding point 13. These allow the tilt angle to be freely set between -10.degree. and +10.degree. by adjusting the parasitic element length and the antenna to be reduced in size.
摘要:
A small antenna comprising a dielectric substrate, a radiation element provided on one major surface of the dielectric substrate, a ground element provided on the other major surface of the dielectric substrate. A feed point on the ground element is located at a position where a voltage of a standing voltage wave induced on the ground element becomes minimum. The antenna may be further provided with a short-circuit element for electrically connecting one ends of the radiation and ground elements.
摘要:
There is provided a panoramic imaging apparatus which serves as a radiation imaging apparatus. The panoramic imaging apparatus includes an X-ray tube radiating an X-ray as a radiation, a detector outputting digital-quantity frame data corresponding to an incident X-ray, and moving means moving the pair of X-ray tube and the detector relatively to an object. The apparatus further includes means for acquiring the frame data from the detector during movement of the X-ray tube and the detector, and means for optimally focusing a portion being imaged of the object using the acquired data and producing a three-dimensional optimally focused image in which the real size and shape of the portion being imaged are reflected.
摘要:
An adaptive antenna apparatus includes antenna elements. One of the antenna elements has an electrical length L1 larger than λ/2, and equal to or smaller than a predetermined upper-limit wavelength, where λ is a wavelength of a radio signal. Another antenna element has an electrical length L2 equal to or larger than a predetermined lower-limit wavelength and equal to or smaller than λ/2. A controller adaptive-controls the adaptive antenna apparatus to form a radiation pattern of the adaptive antenna apparatus including a plurality of nulls substantively in a direction of an interference wave by adjusting at least one of an amplitude and a phase of each radio signal received by the first and second antenna elements.
摘要:
An adaptive antenna apparatus is provided with a total of four or more, even number N of antennas including a plurality of pairs of antennas each having a bidirectional characteristic. The N antennas are provided respectively at vertexes of a polygon of the same number as the number N of the antennas, so that each pair of antennas of the plurality of pairs of antennas opposes to each other. An adaptive control circuit takes an adaptive control over radio signals using one pair of antennas opposing to each other among the N antennas. In the adaptive antenna apparatus, the each pair of antennas is provided to oppose to each other so that axes of directions of main beams of the directional characteristics of the each pair of antennas substantially coincide with each other.
摘要:
A disc autochanger improving on a conventional disc separating mechanism to enable the device to be reduced in size is provided, comprising a plurality of disc holding members 4 (4-1 to 4-6), a splitting member 21 splitting the plurality of disc holding members 4 to separate them at the disc holding member for playback/recording, and an elevator mechanism 6 making the plurality of disc holding members 4 move in the elevation direction to make the disc holding member for playback (recording) move to the position for splitting the disc holding members and further enlarge the split.
摘要:
The objective of the present invention is to provide an optical disc which solves the problem that search for data recorded on an exchange-type medium such as an optical disc and the like and which allows search for data recorded in an optical disc to be performed with a simple operation. A transmitting/receiving antenna 231 is provided in an inner peripheral portion of an optical disc. An IC module 201 connected with transmission/reception IC 230 including ID information is formed and embedded into a substrate the optical disc. Thus, an optical disc incorporating an IC module which can be produced on a mass-production basis can be achieved.
摘要:
There is provide a mobile radio apparatus capable of suppressing a mismatching loss, and increasing a transmission/reception sensitivity by means of instantly and adaptively matching the impedance between the antenna and the transmission/reception circuit whatever situation a mobile radio apparatus, such as a mobile phone or the like, may be. In a mobile radio apparatus (1), when starting control of the matching circuit (102), a control section (105) evaluates an initial chromosome stored in a storage section (106), and if there is an initial chromosome for providing an impedance matching, controls the matching circuit (102) so as to have a load value corresponding to this initial chromosome. If there is no initial chromosome for providing the impedance matching, the control section (105) evolves the initial chromosome with a genetic algorithm, derives a chromosome for providing the impedance matching, and controls the matching circuit (102) so as to have a load value corresponding to the derived chromosome.
摘要:
In an apparatus for measuring a specific absorption rate (SAR), a first near magnetic field distribution of a radio wave radiated from an array antenna of a reference antenna including a plurality of minute antennas is measured, and an SAR distribution with respect to the radio wave radiated from the array antenna is measured with a predetermined phantom. Then a distribution of a transformation coefficient α is calculated by dividing the measured SAR distribution by a square of the measured first near magnetic field distribution, a second near magnetic field distribution of a radio wave radiated from a measured radio communication apparatus is measured, and an SAR distribution with respect to the radio wave radiated from the radio communication apparatus is calculated by multiplying a square of the measured second near magnetic field distribution by the calculated distribution of the transformation coefficient α.
摘要:
An antenna matching apparatus capable of eliminating impedance mismatching produced when the antenna element is placed close to the human body in a short time and reducing power loss due to impedance mismatching. This apparatus connects variable capacitance capacitors VC1 and VC2 for impedance adjustment to transmission antenna element TA1, connects variable capacitance capacitors VC3 and VC4 to reception antenna element RA1 respectively, provides beforehand capacitance values of respective variable capacitance capacitors which are impedance matched in a table in a one-to-one correspondence with the distances between the antenna elements and human body and stores the table in storage section (106). The apparatus completes adaptive control processing for any one of transmission antenna element TA1 and reception antenna element RA1, reads other capacitance values corresponding to the capacitance value at that moment from the table and performs adaptive control processing on other antenna elements using the read values as initial values.