摘要:
A compact, low cost antenna communicates with low and medium earth orbit satellites. The antenna includes a plurality of micro-strip elements arranged about an axis and positioned to illuminate upper elevation angles. The micro-strip elements are perpendicular to each other and are oriented toward the horizon at 90 degree increments. Furthermore, the micro-strip elements are tilted at a 50 degree angle. A quadrifilar helix is positioned at the center of the micro-strip elements and positioned to illuminate lower elevation angles. The micro-strip elements generate an omni-directional field pattern in the azimuth plane. The quadrifilar helix generates a high-gain, narrow beam-width field pattern that is also omni-directional in the azimuth plane. The antenna provides improved immunity to specular ground reflections by limiting reception of signals below a threshold elevation angle. Also, the antenna provides continuous, uninterrupted communications by eliminating "dead" period associated with conventional parabolic dish antennas.
摘要:
A ground station antenna array includes a first array of antenna elements. A second array of antenna elements are vertically aligned with the first array of antenna elements. The first array of antenna elements and the second array of antenna elements are coupled to the digital beam forming circuitry and each cover a same sector of azimuth; the first array of antenna elements only covering a first elevation; the second array of antenna elements only covering a second lower elevation. The digital beam forming circuitry directs a radiation pattern of the first array of antenna elements in a first range of elevation angles, and directs a radiation pattern of the second array of antenna elements in a second range of elevation angles. The second array of antenna elements has higher gain than the first array. A respective transceiver is coupled to respective antenna elements of the first and second arrays.
摘要:
The present invention represents an integrated antenna assembly comprising a cellular communications antenna and a satellite communications antenna. Such an antenna assembly can, therefore, be used for communications over either frequency range. A wireless telephone using this assembly can, therefore, operate with either a terrestrial cellular communications system or a satellite communications system. In a preferred embodiment of the invention, the satellite communications antenna is a quadrifilar helix antenna and the cellular communications antenna is a sleeve dipole. The whip portion of the sleeve dipole is positioned axially in the center of the quadrifilar helix antenna. This orientation permits operation in both the satellite and cellular frequency ranges without significant electromagnetic coupling.
摘要:
A method for real-time calibration of an air to ground two-way communication system. The method includes calibrating a ground base station antenna array according to forward link calibration coefficients received from an aircraft as part of a communication signaling protocol during operation of the air to ground two-way communication system. The method may also includes communicating between the ground base station antenna array and the aircraft over a narrow beam.
摘要:
A method for ground to air communication includes receiving a first pilot signal on a first wide beam from a first ground base station by a first antenna element covering a first range of azimuth angles from an aircraft. Data is received on a directed data beam from the first ground base station by the first antenna element. A second pilot signal is received on a second wide beam from a second ground base station by a second antenna element covering a second range of azimuth angles different than the first range of azimuth angles. A signal strength of the second pilot signal is compared with a signal strength of the first pilot signal. Data reception is switched from the first antenna element to the second antenna element if the signal strength of the second pilot signal is greater than the signal strength of the first pilot signal.
摘要:
A method for ground to air communication includes receiving a first pilot signal on a first wide beam from a first ground base station by a first antenna element covering a first range of azimuth angles from an aircraft. Data is received on a directed data beam from the first ground base station by the first antenna element. A second pilot signal is received on a second wide beam from a second ground base station by a second antenna element covering a second range of azimuth angles different than the first range of azimuth angles. A signal strength of the second pilot signal is compared with a signal strength of the first pilot signal. Data reception is switched from the first antenna element to the second antenna element if the signal strength of the second pilot signal is greater than the signal strength of the first pilot signal.
摘要:
A method for real-time calibration of an air to ground two-way communication system. The method includes calibrating a ground base station antenna array according to forward link calibration coefficients received from an aircraft as part of a communication signaling protocol during operation of the air to ground two-way communication system. The method may also includes communicating between the ground base station antenna array and the aircraft over a narrow beam.
摘要:
The present invention represents an integrated antenna assembly comprising a cellular communications antenna and a satellite communications antenna. Such an antenna assembly can, therefore, be used for communications over either frequency range. A wireless telephone using this assembly can, therefore, operate with either a terrestrial cellular communications system or a satellite communications system. In a preferred embodiment of the invention, the satellite communications antenna is a quadrifilar helix antenna and the cellular communications antenna is a sleeve dipole. The whip portion of the sleeve dipole is positioned axially in the center of the quadrifilar helix antenna. This orientation permits operation in both the satellite and cellular frequency ranges without significant electromagnetic coupling.
摘要:
An apparatus for wireless charging using radio frequency (RF) energy includes a first charger portion having first and second charging areas. The first and second charging areas are located in a common plane, each having at least one coil for wirelessly charging a charge-receiving device placed in proximity thereto. The coils include respective windings, which are wound in opposing directions, each coil being connected in series, each coil configured to charge at least one charge-receiving device. A second charger portion has a third charging area having at least one coil including a winding for wirelessly charging a charge-receiving device placed in proximity to the third charging area, the coil in the third charging area being connected in series with the coils in the first and second charging areas, the third charging area located in a plane that is orthogonal to the plane of the first and second charging areas.
摘要:
Techniques for adjusting one or more antenna parameters to optimize the performance of a wireless device are disclosed. In an embodiment, a variable antenna electrical length module is provided with a control signal for selecting a preferred antenna electrical length. Further techniques for accommodating multiple antennas are disclosed.