摘要:
Apparatus for receiving super high frequency signals having an outdoor unit which includes a converter for converting super high frequency signals received by an antenna to ultra high frequency signals, a local oscillator for generating a local signal supplied to the converter a switch for switching the frequency of the local signal, and a detecting circuit for detecting an operating voltage supplied to the outdoor unit and the value of which is changed according to a band range of the super high frequency signals, the output of the detecting circuit controlling the switch, an indoor unit which includes a demodulator demodulating the ultra high frequency signals, and a circuit generating the operating voltage; and a coaxial cable supplying the ultra high frequency signals from the outdoor unit to the indoor unit and also supplying the operating voltage from the indoor unit to the outdoor unit.
摘要:
Impedance adjusting elements for a microstrip circuit of the kind employing a signal transmission line connected to an active circuit element and impedance matching elements, such as parallel-connected open-ended stubs, are formed of one or more wire elements arranged in proximity to the transmission line and the open-ended stub and connected at one end to the ground plane on the side of the substrate opposite the transmission line, wherein the free end of the wire elements can be freely moved, thereby adjusting the spacing of the wire elements from the respective signal path and open-ended stub and adjusting the angle of intersection of the wire elements and the respective signal path and open-ended stub, so that the effective impedances of the circuit can be controlled.
摘要:
An antenna apparatus has a first wire-like antenna element formed into a rectangular planar loop and a second antenna element which comprises two L-shaped plates electrically connected to the loop and mounted to a rectangular planar base member. The loop is hinged to the planar base member along long sides of the respective rectangles so that the angle between the planes of the loop and base member is adjustable. The base member pivots about an axis on a mount which can be secured to a television receiver.
摘要:
A planar antenna for circular polarized microwaves incorporates a substrate sandwiched between conductive layers having a plurality of openings arranged in a rectangular array, with a pair of perpendicular excitation probes supported on the substrate in alignment with each opening, and a feed circuit for interconnecting the excitation probes in a predetermined phase relationship. Two additional conductive elements may be supported on the substrate in alignment with the excitation probes to provide improved impedance matching. The feed circuit may incorporate a pair of quarter wavelength feed lines connected to the excitation probes, with a resistance element interconnected between the feed lines. The feed point of the antenna may be located near the center of the array, occupying a position normally occupied by one of the pairs of excitation probes.
摘要:
A suspended line feed type planar antenna is arranged with a number of antenna elements formed on a film-shaped substrate, and the film-shaped substrate is sandwiched between a plastic radome and a plastic rear cover, a conductive surface is plated on the rear surface of the plastic radome at its portion except the portions opposing the antenna elements and/or a conductive surface is plated on the whole front surface of the rear cover. The conductive surfaces and the antenna elements constitute resonance type printed path radiators, whereby the planar antenna of the invention can be simplified in construction and reduced in cost, thickness and weight, and the planar antenna of the invention can be increased in productivity and reliability.
摘要:
A planar array antenna is comprised of an upper plate having a plurality of holes, a lower plate, and a circuit board having printed patterns of a plurality of array elements and located between the upper plate and the lower plate, wherein the lower plate has concave regions formed at positions corresponding to the positions of the plurality of holes of the upper plate.
摘要:
A planar microwave antenna of the suspended line feed type has a substrate sandwiched between a pair of conductive plates, each of the plates having aligned openings defining radiation elements. The substrate is held in place by holding portions surrounding the openings and wide grooves between the openings house a plurality of parallel suspended lines.
摘要:
A receiver device for a satellite communication system capable of transmitting in either of two modes detects which transmission mode is currently in effect and adjusts its signal processing and output stages accordingly. The transmission may be recognized by reference to either the encoded information or the electromagnetic medium itself of the received electromagnetic transmissions. In one mode, only audio signals and related information are broadcast in FM form whereas in the other mode, a video image signal is also included, while a subcarrier signal is modulated by an audio and/or a data signal. The receiver system checks either the sub-carrier signal or video synchronization signals in the incoming transmissions to determine the transmission mode. The receiver may also be forced to a predetermined mode upon power-up to prevent spurious mode-selection errors.
摘要:
A suspended line feed type planar array antenna has a substrate sandwiched between a pair of metal or metallized plastic plates and resonance type printed patch radiators provided in corresponding relation to openings formed through one of the pair of metal or metallized plastic plates, whereby the antenna can be reduced in thickness, weight and cost. Also, the transmission loss of the antenna can be reduced and its bandwidth can be widened.
摘要:
A tuner for use with a television receiver includes a mixer receiving and mixing radio frequency and local oscillator signals and a low-pass peaking circuit for preferentially coupling the intermediate frequency from the mixer to an intermediate frequency amplifier. A capacitor in parallel with a series combination of an inductor and a capacitor in the peaking circuit forms a trap circuit for blocking spurious high-frequency signals from the intermediate frequency amplifier. An emitter follower between the mixer and the intermediate frequency amplifier may be included within the parallel connection.