Abstract: A directional coupler includes a primary transmission line electrically coupled in series between an input port and an output port of the coupler, and an asymmetric, meander-shaped, secondary transmission line, which is electrically coupled in series between a coupling port and an isolation port of the coupler. The secondary transmission line includes a first coupling segment, which is reactively coupled to a first portion of the primary transmission line, and a second coupling segment, which is reactively coupled to a second portion of the primary transmission line, and is spaced closer to, or farther from, the primary transmission line relative to the first coupling segment, such that an asymmetry in reactive coupling is present between the first and second portions of the primary transmission line and the secondary transmission line. An intermediate segment is provided, which is electrically coupled in series between the first and second coupling segments.

Abstract: Base station antennas include an externally accessible active antenna module releasably coupled to a recessed segment that is over a chamber in the base station antenna and that is longitudinally and laterally extending along and across a rear of a base station antenna housing. The base station antenna housing has a passive antenna assembly that cooperates with the active antenna module.

Abstract: Base station antennas include a main module that has a first backplane that includes a first reflector. A vertically-extending array of first radiating elements is mounted to extend forwardly from the first reflector, and at least one first RF port is coupled to the vertically-extending array of first radiating elements. These antennas further include a sub-module that is attached to the first backplane. The sub-module includes a second backplane that has a second reflector that is separate from the first reflector. A vertically-extending array of second radiating elements is mounted to extend forwardly from the second reflector and is transversely spaced-apart from the vertically-extending array of first radiating elements. A plurality of second RF ports are coupled to the vertically-extending array of second radiating elements. The vertically-extending array of first radiating elements and the vertically-extending array of second radiating elements are configured to serve a common sector of a base station.

Abstract: Base station antennas include an externally accessible active antenna module releasably coupled to a recessed segment that is over a chamber in the base station antenna and that is longitudinally and laterally extending along and across a rear of a base station antenna housing. The base station antenna housing has a passive antenna assembly that cooperates with the active antenna module.

Abstract: A multi-mode antenna includes a feed network including a cascaded arrangement of a first phase shifter and hybrid coupler pair, which is responsive to a radio frequency (RF) input feed signal, and a second phase shifter and hybrid coupler pair, which is responsive to an RF feed signal generated at a second output port of the first phase shifter and hybrid coupler pair. First, second and third arrays of radiating elements are provided. The first array is responsive to a RF feed signal derived from a first output port of the first phase shifter and hybrid coupler pair; the second array is responsive to an RF feed signal derived from a first output port of the second phase shifter and hybrid coupler pair; and the third array is responsive to an RF feed signal derived from a second output port of the second phase shifter and hybrid coupler pair.

Abstract: Base station antennas include an externally accessible active antenna module releasably coupled to a recessed segment that is over a chamber in the base station antenna and that is longitudinally and laterally extending along and across a rear of a base station antenna housing. The base station antenna housing has a passive antenna assembly that cooperates with the active antenna module.

Abstract: Base station antennas include an externally accessible active antenna module releasably coupled to a recessed segment that is over a chamber in the base station antenna and that is longitudinally and laterally extending along and across a rear of a base station antenna housing. The base station antenna housing has a passive antenna assembly that cooperates with the active antenna module.

Abstract: A base station antenna includes a first antenna having first and second spaced-apart columns of first radiating elements therein, which are configured to operate within a first frequency band. An active antenna system (AAS) is provided, which is configured to operate within a second, typically higher, frequency band. The AAS includes a second antenna within a space between the first and second columns of first radiating elements. These first radiating elements may include tilted feed stalks which support higher integration by enabling the first radiating elements to overhang at least a portion of the second antenna.

Abstract: A system for generating calibration data in an active antenna system (AAS) radio includes an array of directional couplers within a multi-channel transmit/receive signal path of the AAS radio, and a combiner network electrically coupled to the array of directional couplers. An array of filters is provided within the multi-channel transmit/receive signal path. The array of filters is electrically coupled to antenna-side terminals of the array of directional couplers. A plurality of pairs of transmitters and receivers are provided, which include a transmitter and a receiver that operate as a reference transmitter and a reference receiver, respectively. A removable routing network is provided, which is electrically coupled to antenna-side terminals of the array of filters, and is configured to feed back factory calibration signals (generated by the AAS radio during factory calibration) to antenna-side terminals of the array of filters.

Abstract: Base station antennas include a main module that has a first backplane that includes a first reflector. A vertically-extending array of first radiating elements is mounted to extend forwardly from the first reflector, and at least one first RF port is coupled to the vertically-extending array of first radiating elements. These antennas further include a sub-module that is attached to the first backplane. The sub-module includes a second backplane that has a second reflector that is separate from the first reflector. A vertically-extending array of second radiating elements is mounted to extend forwardly from the second reflector and is transversely spaced-apart from the vertically-extending array of first radiating elements. A plurality of second RF ports are coupled to the vertically-extending array of second radiating elements. The vertically-extending array of first radiating elements and the vertically-extending array of second radiating elements are configured to serve a common sector of a base station.

Abstract: Active antenna units and/or base station antennas are provided that include a reflector body with heat dissipation structures that can be directly exposed to environmental conditions during use. The heat dissipation structures have frequency selective surfaces and can be formed of sheet metal or provided as separate extruded or die cast members that can be coupled to the reflector body.

Abstract: The present application is directed to a mounting system for a base station antenna. The system includes a passive antenna and an active antenna module and a mounting kit. The mounting kit includes an upper radio mounting bracket assembly and a lower radio mounting bracket assembly, and is configured to mount and secure an upper portion of the passive antenna to a mounting structure and mount and secure the active antenna module to the mounting structure behind the passive antenna. The system further includes a middle antenna mounting bracket assembly configured to pivotably mount a middle portion of the passive antenna to the mounting structure and a lower antenna mounting bracket assembly configured to slidably and/or pivotably mount a lower portion of the passive antenna to the mounting structure. The mounting system is configured to adjust the base station antenna downwardly or upwardly to a desired angle of tilt. Mounting kits and methods of operating same are also described herein.

Abstract: A base station antenna includes a plurality of pairs of RF ports, a tubular reflector, a plurality of columns of first frequency band radiating elements that are mounted to extend outwardly from the tubular reflector, the columns extending around a periphery of the tubular reflector and grouped into a plurality of column groups, where each column group includes at least three columns, and a plurality of feed networks, where each feed network connects one of the pairs of RF ports to a respective one of the column groups.

Abstract: Radiating elements of first and second linear arrays of radiating elements have respective feed stalks that can reside at an angle to provide a balanced dipole arm with an inner end portion laterally offset to be closer to a right or left side of the base station antenna and reflector than an outer end portion that faces a radome of the base station antenna. The feed stalk can include sheet metal legs and printed circuit boards providing an RF transmission line(s).

Abstract: Antenna systems are provided. An antenna system includes a beamforming array having a plurality of vertical columns of radiating elements that are each configured to transmit at least three antenna beams per polarization. Moreover, the antenna system includes a beamforming radio having a plurality of radio frequency ports per polarization that are coupled to and fewer than the vertical columns.

Abstract: The present invention provides an image recognition method, an electronic device and a computer-readable storage medium. The method includes: segmenting an original image into a plurality of unit images having the same predetermined size; inputting the unit images into a pre-built neural network model to carry out processing, so as to correspondingly add a detection frame to a marker in each unit image to form a pre-detection unit image; stitching a plurality of pre-detection unit images into a pre-output image according to segmentation positions of each unit image in the original image; determining whether the markers selected in two adjacent detection frames in the pre-output image are the same marker; outputting the image with the detection frames until all the detection frames confirmed to have the same markers are all merged. The present invention can effectively recognize types and positions of the markers in the image.

Abstract: An integrated base station antenna includes a feed board having a plurality of columns of radiating elements mounted thereon and a plurality of phase shifters coupled to the plurality of columns of radiating elements mounted on a same side of the feed board as the plurality of columns of radiating elements.

Abstract: Base station antennas include an externally accessible active antenna module releasably coupled to a recessed segment that is over a chamber in the base station antenna and that is longitudinally and laterally extending along and across a rear of a base station antenna housing. The base station antenna housing has a passive antenna assembly that cooperates with the active antenna module.

Abstract: An automatic identification method and an identification system for a gastrointestinal marker are provided. The automatic identification method comprises the following steps: determining a suspected gastrointestinal marker region in an image; removing an overlapping suspected gastrointestinal marker region; and determining whether the suspected gastrointestinal marker region is part of the gastrointestinal marker. In the method, by means of processing and analyzing an image, positions of a gastrointestinal marker in the image can be automatically detected.

Abstract: Devices having bypassable radio frequency (RF) filters are provided. A device includes a bypassable RF filter and an adjustable-length RF transmission line that is coupled thereto. Moreover, the device includes a component that is coupled to the adjustable-length RF transmission line and is configured to change an electrical length of the adjustable-length RF transmission line between a first length and a second length. Related methods of bypassing the bypassable RF filter are also provided.