摘要:
Method and apparatus for feeding a compact main reflector of an RF antenna on a plurality of spectrally offset frequency bands. The method can include the steps of forming a focal ring for a main reflector (304) by positioning an RF source (301) at a first frequency within a first frequency band in the far field relative to a shaped non-linear surface of revolution so that the shaped non-linear surface of revolution forms a subreflector (302). A second focal ring can be formed for the main reflector (304) by positioning a second RF source (300) in the nearfield of the shaped non-linear surface of revolution.
摘要:
A waveguide horn antenna includes a horn-shaped body portion and one or more feed structures. Each feed structure includes feed locations positioned between spaced apart ends of the body portion according to short circuit locations of desired frequencies to facilitate propagation of electromagnetic energy at the desired frequencies. Multiple frequency bands can be supported with the antenna by employing more than one axially spaced apart feed structures having associated feed locations arranged along the body portion of the antenna.
摘要:
A primary radiator used for a parabolic antenna including: a radiator body having a horn part provided at one end of a waveguide; and a waterproof cover covering an open end of the horn part of the radiator body, wherein a step is formed on an inner surface of the horn part of the radiator body, and a position of the step is set so that radio waves reflected on the waterproof cover are cancelled out by radio waves reflected on the step to prevent multiple reflection in the radiator body.
摘要:
A multi-mode, multi-choke feed horn that employs a plurality of chokes designed to excite the proper mode content in a satellite uplink signal or downlink signal over a particular wide bandwidth. In one embodiment, the feed horn includes five chokes, where the choke closest to the feed end of the horn has a depth of about 0.075null.
摘要:
Disclosed are systems and methods which provide multi-band antenna elements using multiple radiating branches interconnected with a feed plate, thereby providing a multi-band antenna element having a single feed. Additionally or alternatively, a wide band antenna configuration is provided utilizing multiple radiating branches of a multi-band antenna element of the present invention. Embodiments utilize one or more reflectors, such as to provide directivity and/or radiation pattern shaping, including utilizing one or more radiating branches of a multi-band antenna element as a reflector for another one or more radiating branches of the multi-band antenna.
摘要:
Provided is a circular pole piece that contributes to simplification of work and a reduction in costs and that has no gap created among adjoining blocks. A circular pole piece is manufactured by circularly arranging laminate blocks each having numerous hexagonal directional magnetic steel sheet tiles layered. Since heteromorphic soft magnetic material tiles are unnecessary, work can be simplified and the cost of the circular pole piece can be reduced. Moreover, the laminate blocks can be arranged substantially circularly without a gap among adjoining blocks.
摘要:
A device for receiving/transmitting electromagnetic signals from/to at least two satellites fixedly located at points at the geostationary path comprises an antenna, for example a lens (1) of waveguide nature. The antenna images remote points at a focal surface and in the points where the satellites are imaged receiver horns (23, 23null) are placed. The horns are adjustably mounted to a rail (21) of a mounting unit (9) except the central horn (23null) that is fixedly placed for receiving along the optical axis of the antenna, at a predetermined distance of the antenna. The rail is mounted to be rotated about the optical axis of the antenna, this giving a simple adjustment of the other horns (23). Using an adjusting assembly the curvature of the rail can be varied to be adapted to receiving at different latitudes.
摘要:
Paraboloidal antennas are common for very high frequencies (VHF) and into the cellular telephone systems and personal communication systems (PCS). Paraboloidal antennas are often used at the base station of either cellular telephone antennas, PCS antennas or both. To avoid possible channel drop out because a sharp focal point of the antenna is misaligned by improper installation or harsh weather conditions. For base stations for cellular telephone systems and/or systems, PCS, a generally paraboloidal antenna that has a less sharp focal point so there is a antenna lower gain, but less relative signal degradation because of weather or other misalignment of the antenna. In such cases, the lower gain, but higher immunity to drop-out more than justifies such arrangements.
摘要:
A radar horn antenna in which, to reduce or remove unnecessary echo from a specific angular range such as ground clutter, divergence in axial direction of a horn antenna 8 accommodated in a casing and covered with a radome is asymmetrical with respect to the axis of the horn antenna so that a maximum radiation direction in a radiation pattern of the horn antenna is deviated from front to another and/or gain in the specific angular range is controlled.
摘要:
A ring focus antenna and method of using same. The ring focus antenna can have a main reflector of revolution shaped as a non-regular paraboloid about a boresight axis of the antenna. A sub-reflector/feed pair is provided comprising a sub-reflector of revolution shaped as a non-regular ellipsoid having a ring-shaped focal point about the boresight axis. A feed element is installed at a feed element location separated spaced from a vertex of the sub-reflector on the boresight axis of the antenna. The main reflector is adapted for operation with multiple sub-reflector/feed pairs having a coupled configuration, and multiple sub-reflector/feed pairs having a decoupled configuration (i.e. classical optical dual reflector system). The main reflector is operable at a plurality of spectrally offset frequency bands. For example, the antenna can be designed for operation over C-band, X-band, Ku-band, and Ka-band.