SYSTEM AND METHOD FOR MAST VIBRATION COMPENSATION

• US 20110070855A1
• Filed: 05/23/2008
• Published: 03/24/2011
• Est. Priority Date: 05/23/2008
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Mariotti, Marco
• Granted Patent: US 9,397,383 B2
• Time in Patent Office: Days
• US Class Current: 455/226.2
• CPC Class Codes: H01Q 1/005 Damping of vibrations; Means for reducing wind-induced forces
• CPC Class Codes: H01Q 1/1242 Rigid masts specially adapted for supporting an aerial
• CPC Class Codes: H01Q 1/185 by electronic means
• CPC Class Codes: H01Q 3/26 varying the relative phase or relative amplitude of energisation between two or more active radiating elements; varying the distribution of energy across a radiating aperture H01Q3/12, H01Q3/22, H01Q3/24 take precedence
• CPC Class Codes: H04B 17/12 of transmit antennas, e.g. of the amplitude or phase
• CPC Class Codes: H04B 17/21 for calibration; for correcting measurements

Abstract

The present invention relates to a system for mast vibration compensation implemented in a communication system including a first node and a second node. The first node comprises a first adaptive antenna mounted in a mast; a receiver connected to said antenna; and a spatial and temporary processing system. The first adaptive antenna is controlled by a first correction signal generated in the spatial and temporary processing system. The correction signal is based on a parameter that indicates that a radio link alignment with a second node is degrading due to mechanical vibrations in the mast. The invention also relates to a method for mast vibration compensation.

Claims

1. A system for mast vibration compensation implemented in communication system comprising:

a first node and a second node, wherein the first node comprises

a first adaptive antenna;

a receiver connected to the first adaptive antenna;

a spatial and temporary processing system, wherein the first adaptive antenna is controlled by a first correction signal generated in the spatial and temporary processing system, and wherein the first correction signal is based on a parameter that indicates that a radio link alignment with the second node is degrading.

2. The system according to claim 1, wherein the parameter is obtained from the receiver in the first node and the system further comprising means to determine a fade rate of main propagation effects in order to ensure that the parameter indicates that the radio link alignment is degrading due to mechanical vibrations.

3. The system according to claim 2, wherein the determined fade rate is in the order of hundreds of Hz to indicate mechanical vibrations.

4. The system according to claim 1, wherein the first adaptive antenna is provided with means to calculate eigenvalues of a receive phase matrix E_RX, and a phase control circuit adapted to adjust an antenna beam in order to maximize the parameter based on the calculated eigenvalues E_RX.

5. The system according to claim 1, wherein the second node comprises a second adaptive antenna connected to a transmitter, wherein the transmitter is adapted to transmit a signal which is received by the receiver in the first node;

and

wherein the second adaptive antenna is controlled by a second correction signal generated in the spatial and temporary processing system shared by the first and second node.

6. The system according to claim 5, wherein the first adaptive antenna is provided with means to calculate eigenvalues of a receive phase matrix E_RX,

wherein the first node is provided with means to retrieve eigenvalues of a transmit phase matrix E_TX of the second adaptive antenna, and

wherein the first adaptive antenna further comprises a phase control circuit adapted to adjust an antenna beam in order to maximize the parameter based on the calculated eigenvalues of the receive phase matrix E_RX and the retrieved eigenvalues of a transmit phase matrix E_TX.

7. The system according to claim 5, wherein the transmitter is implemented in a transceiver circuit.

8. The system according to any of claim 1, wherein the parameter is received signal strength indication (RSSI).

9. The system according to any of claim 1, wherein the receiver is implemented in a transceiver circuit.

10. A method for compensating for mast vibrations in a communication system, comprising:

measuring a parameter in a first node received by a first adaptive antenna, wherein the parameter indicates that a radio link alignment with a second node is degrading,

generating a correction signal in a spatial and temporary processing system based on the measured parameter, and

controlling the first adaptive antenna by the correction signal.

11. The method according to claim 10, further comprising:

determining a fade rate of a main propagation effect in order to ensure that the measured parameter indicates that the radio link alignment is degrading due to mechanical vibrations before the correction signal is generated.

12. The method according to claim 11, further comprising:

calculating eigenvalues of a receive phase matrix E_RX, and,

adjusting an antenna beam in order to maximize the parameter based on the calculated eigenvalues E_RX.

13. The method according to claim 10, further comprising:

transmitting a signal from the second node which is received by the receiver, and

selecting the spatial and temporary processing system to be shared by the first and second node, wherein the generated correction signal is further based on the transmitted signal.

14. The method according to claim 13, further comprising:

calculating eigenvalues of a receive phase matrix E_RX,

retrieving, in the first node, eigenvalues of a transmit phase matrix E_TX of the second adaptive antenna, and

adjusting an antenna beam in order to maximize the parameter based on the calculated eigenvalues of the receive phase matrix E_RX and retrieved eigenvalues of the transmit phase matrix E_TX.

15. The method according to claim 10, further comprising selecting the parameter to be received signal strength indication (RSSI).