Abstract: A method for antenna calibration is disclosed, the method including driving calibration signals for antenna array beam calibration to an antenna array feeder line in a transceiver front end unit by using one or more directional couplers and/or radio frequency probes, wherein calibration signal paths are integrated inside the transceiver front end unit. Measurements are carried out on the calibration signals, between different antenna combinations inside the antenna array. Based on collected measurement data, calibration information is calculated for each measurement branch of the antenna array by using a mathematical formula. Active antenna array beam calibration is then performed based on the calculated calibration information.

Abstract: There is provided a method, including obtaining, by a network apparatus, antenna sensing information with respect to signals received by a base station operating under a shared access-system which allows a licensee system to apply at least a part of an shared access spectrum which is currently unused by an incumbent system; detecting, on the basis of the antenna sensing information, that at least one device of the incumbent system is communicating on the shared access spectrum in the coverage area of the base station; identifying the angular sector in which the device of the incumbent system is located with respect to the base station; and dynamically isolating the identified angular sector from usage by the licensee system.

Abstract: A method for antenna calibration is disclosed, the method including driving calibration signals for antenna array beam calibration to an antenna array feeder line in a transceiver front end unit by using one or more directional couplers and/or radio frequency probes, wherein calibration signal paths are integrated inside the transceiver front end unit. Measurements are carried out on the calibration signals, between different antenna combinations inside the antenna array. Based on collected measurement data, calibration information is calculated for each measurement branch of the antenna array by using a mathematical formula. Active antenna array beam calibration is then performed based on the calculated calibration information.

Abstract: There is provided a method, including obtaining, by a network apparatus, antenna sensing information with respect to signals received by a base station operating under a shared access-system which allows a licensee system to apply at least a part of an shared access spectrum which is currently unused by an incumbent system; detecting, on the basis of the antenna sensing information, that at least one device of the incumbent system is communicating on the shared access spectrum in the coverage area of the base station; identifying the angular sector in which the device of the incumbent system is located with respect to the base station; and dynamically isolating the identified angular sector from usage by the licensee system.

Abstract: A Vivaldi antenna is disclosed, including an antenna upper part, and an antenna throat, wherein the antenna upper part is tilted, in respect to the antenna throat, at a predetermined location of the antenna upper part. The antenna upper part may be tilted, in respect to the antenna throat, by one or more predetermined tilted angles respectively at one or more predetermined locations of the antenna upper part. A corresponding antenna pair, antenna array and base station are also disclosed.

Abstract: A method is disclosed for antenna calibration in communications, the method co icing creating an uplink calibration signal for active antenna or antenna array uplink calibration, at a baseband part of a transmitter directly to a selected duplex spacing or another specified spacing from a transmission signal inside a baseband output sampling rate spectrum of the transmitter. Measurements are carried out on the uplink calibration signal. Based on collected measurement data, calibration information is calculated. The active antenna or antenna array uplink calibration is performed based on the calculated calibration information.

Abstract: A method of calibrating an active antenna and an active antenna is disclosed, wherein the active antenna is designed to be used in a base transceiver station for mobile communication. Firstly, at least one receiver of the active antenna is correlated to a calibration signal. Secondly, a received phase pattern is analyzed. Then, the active antenna is adjusted until all receivers receive substantially in equiphase. Finally, a beam forming function and a phase pattern are applied as forward adjustment to the active antenna.