Repeaters for wireless communication systems
View Patent ↗A repeater and associated method of use includes at least one antenna element for communicating in one direction and at least one antenna element for communicating in another direction. A radio frequency uplink path and a radio frequency downlink path are coupled between the antennas. At least one of the radio frequency uplink path or the radio frequency downlink path includes an adaptive cancellation circuit. The adaptive cancellation circuit is configured to generate a cancellation signal without requiring an injected signal. The cancellation signal, when added to a radio frequency signal in the respective uplink and downlink paths, substantially reduces feedback signals present in the radio frequency signal.
1. A modular device for repeating RF communication signals, the device comprising:
a planar housing that has height and width dimensions that are a multiple of the thickness dimension, the planar housing defining a plane and having generally oppositely facing surfaces;
at least one antenna positioned on each of said generally oppositely facing surfaces for radiating energy from each of the surfaces;
at least one of the antennas on a surface configured to act as a transmit antenna for transmitting RF communication signals and at least one antenna on an oppositely facing surface configured to act as a receive antenna for receiving RF communication signals;
electronic circuitry positioned in the planar housing and operatively coupling the receive antenna to circuitry for handling the received RF communication signals and operatively coupling the transmit antenna to circuitry for providing RF communication signals to transmit;
the planar housing including at least one planar layer positioned parallel to the plane of the housing between the oppositely facing surfaces and antennas positioned thereon, the planar layer configured to block RF communication signals of one antenna from being received by the other antenna for providing side-to-side isolation between the antennas.
2. The device of claim 1 , wherein said antennas each comprise at least one radiating antenna element located centrally on an associated ground plane of the planar housing, the ground plane having sufficient area to contribute to significant feedback suppression between the antennas.
3. The repeater of claim 1 , wherein at least one of the antennas radiates with a first polarization and an antenna on an oppositely facing surface radiates with a second polarization orthogonal to the first polarization.
4. The device of claim 1 wherein
at least one of said antennas includes a ground plane and one or more radiating elements positioned in a central area of said ground plane, the area of said ground plane being greater than the area of said central area wherein the ratio of ground plane area to central area is in the range of about 2 to 5.
5. The device of claim 1 further comprising a plurality of antennas positioned on at least one of the oppositely facing surfaces.
6. The device of claim 1 wherein at least one of the oppositely facing surfaces is flat.
7. The device of claim 1 wherein at least one of the oppositely facing surfaces is shaped.
8. The device of claim 1 , wherein at least one of said antennas is operable to produce a null in the array factor on the horizons to reduce the direct coupling between said antennas.
9. The device of claim 1 , said planar housing being sized and configured for a selected frequency band having a predetermined center frequency with wavelength “X”, the height, width and thickness dimensions of the housing being such that feedback energy as wavelength X travels a feedback path around the housing improves side-to-side isolation.
10. The device of claim 9 , wherein said planar housing has at least one of a circular outer configuration or a rectangular outer configuration.
11. The device of claim 1 , the planar housing including an RF choke structure in the feedback path between said antennas positioned on the oppositely facing surfaces.
12. The device of claim 11 , wherein the choke structure includes a plurality of fins around the planar housing.
13. The device of claim 12 wherein the fins have at least one of height and spacing dimensions related to one quarter wavelength of a center frequency of a band of frequencies handled by the device.
14. The device of claim 12 wherein an outermost of fins has the greatest height and successively inward fins have progressively decreasing height.
15. The device of claim 11 , wherein the choke structure includes a plurality of peripherally extending fins around the planar housing.
16. The device of claim 11 , wherein the choke structure includes a plurality of concentric fins extending orthogonal to the plane of the planar housing.
17. The device of claim 1 wherein
at least one antenna is mounted to extend upwardly from and adjacent to one of the oppositely facing surfaces of said housing.
18. The device of claim 17 , wherein the at least one antenna mounted to extend upwardly is one of a monopole and a dipole.
19. The device of claim 1 wherein the at least one planar layer positioned parallel to the plane of the housing between the oppositely facing surfaces and antennas is a ground layer.
20. A modular device for repeating RF communication signals, the device comprising:
a planar housing that has height and width dimensions that are a multiple of the thickness dimension, the planar housing defining a plane and having generally oppositely facing surfaces;
at least one antenna positioned on each of said generally oppositely facing surfaces for radiating energy from each of the surfaces;
at least one of the antennas on a surface configured to act as a transmit antenna for transmitting RF communication signals and at least one antenna on an oppositely facing surface configured to act as a receive antenna for receiving RF communication signals;
electronic circuitry positioned in the planar housing and operatively coupling the receive antenna to circuitry for handling the received RF communication signals and operatively coupling the transmit antenna to circuitry for providing RF communication signals to transmit;
the planar housing including at least one planar layer positioned parallel to the plane of the housing between the oppositely facing surfaces and antennas positioned thereon.