摘要:
A cavity filter which provides for fine tuning of the bandwidth of the filter. The filter provides for both capacitive cross-coupling and inductive coupling between physically adjacent but electrically non-adjacent resonators in the filter. The isolation of the filter can be fine tuned by adjusting the inductive coupling between these resonators, which has the effect of attenuating the cross-coupling effect between these resonators.
摘要:
A microwave coupler has a planar form with a transmission line segment oriented at an angle relative to a main transmission line. The planar form of the transmission line, such as in a printed circuit board, helps reduce the size and manufacturing costs for the coupler. When placed a prescribed distance from the main transmission line and oriented at an appropriate angle, the directivity and coupling factor requirements can be met precisely with minimal tuning. Where fine tuning is required, a tuning screw and resistor disposed adjacent to the transmission line segment are provided.
摘要:
This invention relates to a one step coaxial connector for an annular corrugated coaxial cable. The components of the connector include an outer conductor clamping back nut, a collet and a body. The collet (1) enhances electrical performance by providing a full 360 degree contact with the outer conductor. In addition, an O-ring is used to provide a seal between the back nut and outer conductor of the cable. When the backnut (2) is screwed into the body (5), the collet (1) is forced further into the interior portion (11) of the connector body (5). The resilient fingers of the (1) collet are forced to close radially around the first corrugation groove (3) of the cable's outer conductor. In addition, an O ring (4), that initially resides in a cavity (12) created by the collet (1) and the back nut (2), is forced into a corrugation groove of the cable's outer conductor. A bore (6) on the back nut (2) provides the proper diameter to compress the O-ring (4) to provide a tight seal.
摘要:
A microstrip antenna suitable for omnidirectional S-band operation is formed by the application of a plurality of microstrip radiating elements to the exterior surface of a dielectric tube. The microstrip radiating elements are fed by a branched microstrip input feed line connected to the elements. In the illustrated embodiment, the microstrip radiating elements are fed in-phase by feed line. A substantially cylindrical reflector tube is disposed within the dielectric tube.
摘要:
A fixed radius tapered slot antenna ( 100 ) formed a dielectric substrate ( 10 ) with an electrically conductive layer ( 14 ) on one side. The slot is defined by two hemispherical shaped elements ( 12, 13 ). A common base ( 15 ) is also formed on the conductive layer behind the hemispherical shaped members. Preferably, a microstrip feedline ( 16 ) is formed on the side of the dielectric substrate to electromagnetically couple to the balun (18) adjacent the narrow end of the tapered slot. A contiguous array of fixed radius tapered slot antennas ( 100 ) can he made on the same conductive layer of a dielectric layer. A reflector can he integrated with the antenna array to improve the radiation pattern. The fixed radius tapered slot antenna has been proven to out-perform an exponentially tapered slot or Vivaldi antenna.
摘要:
A land mobile radio system (110) includes a plurality of receive antenna (120) for receiving RF signals transmitted from mobile units. Each receive antenna (120) is connected to a transform matrix (133) which divides each received RF signal into a number, N, of transformed signals, each transformed signal containing an equal power level part, 1/N, of each received RF signal. Each transformed signal is provided to an amplifier (135) for amplification thereof, and the amplified transformed signals are provided to an inverse-transform matrix (138) which recombines the equal parts of each amplified transformed signal into amplified received RF signals which are provided to an RF signal processing section (125). The amplified RF signals are thereafter provided to corresponding radio channel units (127).
摘要:
An apparatus for communicating, over a single transmission medium, two signals of substantially the same center frequency. The apparatus offsets in frequency one of the signals by combining the signal with the signal from a local oscillator. The apparatus then transmits the two signals, one offset from the other, as well as the signal from the local oscillator to allow for recovery of the two signals with a precise correction for the offset. In particular, the transmission medium is an optical fiber and the two signals are a main RF signal and a diversity RF signal received, respectively, by a main element and a diversity element of a diversity antenna system. The invention is of use, for example, in providing to a microbase station a main RF signal and its diversity RF signal received at a diversity antenna system remote from the microbase station and connected to the microbase station by an optical fiber.
摘要:
In a radiating coaxial cable, the outer-conductor having a plurality of radiating apertures is wrapped in a tape of conducting material which covers some of the apertures. In one embodiment of the invention, the conductive tape is combined with a fire retardant tape so that one winding procedure will result in winding both the conductive tape and the fire retardant tape over the outer-conductor.