Abstract: A method and apparatus for selectively adjusting transmit diversity parameters in a mobile communication system including a mobile device and a base station. The mobile device transmits a signal set comprised of a plurality of signals differing only in phase from one another, receive in response an input parameter for each set, and adjust the phase difference of a subsequently transmitted signal set as a function of the input parameters.

Abstract: A method and apparatus for selectively adjusting transmit diversity parameters in a mobile communication system including a mobile device and a base station. The mobile device transmits a signal set comprised of a plurality of signals differing only in phase from one another, receive in response an input parameter for each set, and adjust the phase difference of a subsequently transmitted signal set as a function of the input parameters.

Abstract: A method and system for improving closed loop feedback in transmit diversity communication. In one embodiment of the invention, a predetermined variation of one or more transmit diversity parameters is performed at the transmit diversity transmitter. The receiver compares the transmit diversity parameter values of the received signals to the predetermined variation and transmits to the transmitter a value of a transmit diversity correction parameter. The transmitter may use this correction value to modify the transmit diversity parameter in a subsequent transmission.

Abstract: A tester for determining phase discontinuity is described for a transmitter having multiple antennas sending signals to a receiver. Typically the transmitter is provided in a mobile telephone and the receiver is in a base station. The transmitter sends out the RF signals in a shaped beam using transmission diversity. The RF signals define multiplexing slots. The tester receives the RF signals as they are fed to a respective antenna port, analyses phases of these signals on a slot-by-slot basis comparing phase differences between adjacent slots to a threshold derived from legacy devices.

Abstract: A method and apparatus for selectively adjusting transmit diversity parameters in a mobile communication system including a mobile device and a base station. The mobile device transmits a signal set comprised of a plurality of signals differing only in phase from one another, receive in response an input parameter for each set, and adjust the phase difference of a subsequently transmitted signal set as a function of the input parameters.

Abstract: A method and system for improving closed loop feedback in transmit diversity communication. In one embodiment of the invention, a predetermined variation of one or more transmit diversity parameters is performed at the transmit diversity transmitter. The receiver compares the transmit diversity parameter values of the received signals to the predetermined variation and transmits to the transmitter a value of a transmit diversity correction parameter. The transmitter may use this correction value to modify the transmit diversity parameter in a subsequent transmission.

Abstract: A signal is modified according to a current diversity parameter adjustment, and is transmitted from a modifying communication device to a feedback communication device. A feedback signal reflecting feedback information describing the signal as received by the feedback communication device is received. The feedback signal comprises frames, and a frame comprises slots, where a slot has a slot power value. The frame timing of the frames is established from the slot power values. The signal is modified according to a next diversity parameter adjustment in accordance with the frame timing.