Method and system for reducing the effect of signal-interference in null areas caused by one or more antennas

A base station for use in a wireless telecommunications network wherein a plurality of base stations may simultaneously transmit signals which overlap, the base station comprising:

• means for determining whether a static null area exists in a region covered by a base station, the static null area being caused by interference between two or more overlapping signals;
• and
• a circuit for effecting a dithering change in a transmission parameter of a signal transmitted from the base station in accordance with a control signal with synchronization time marks for aligning the dithering change, thereby shifting the static null area in the region covered by the base station.

In a radio communications network, a method of operating a base station in coordination with other simulcasting base stations within reception proximity, the method comprising:

• determining whether a static null area exists in a region covered by a base station, the static null area being caused by interference between two or more overlapping signals transmitted from the base station and other simulcasting base stations;
• and
• if it is determined that a static null area exists in the region, effecting a dithering change in a transmission parameter of a signal transmitted by the base station in accordance with a control signal with synchronization time marks for aligning the dithering change, thereby altering null areas resulting from the overlapping signals.

In a wireless telecommunications network having a plurality of base stations that may simultaneously transmit to wireless transmit and receive units (WTRUs), a method comprising:

• determining whether a static null area exists in a region covered by a base station, the static null area being caused by interference between two or more overlapping signals transmitted from the base station and from at least one other base station;
• and
• effecting a dithering change in a transmission parameter of a signal in the overlapping region in accordance with a control signal with synchronization time marks for aligning the dithering change, thereby altering a pattern of interference null areas resulting from the overlapping signals.

A base station for use in a wireless telecommunications network and having an antenna whose signal is subject to multipath, the base station comprising:

• means for determining whether a static null area exists in a region covered by the base station, the static null area being caused by interference between two or more overlapping signals;
• and
• a circuit for effecting a dithering change in a transmission parameter of the signal in a region having overlapping signals in accordance with a control signal with synchronization time marks for aligning the dithering change, thereby shifting the null area in the region covered by the base station.

In a wireless telecommunications network having a plurality of base stations that may simultaneously transmit to wireless transmit and receive units (WTRUs), a method comprising:

• determining whether a static null area exists in a region covered by a base station, the static null area being caused by interference between two or more overlapping signals which are multipath components transmitted from the same base station;
• and
• effecting a dithering change in a transmission parameter of the signal transmitted from the base station in accordance with a control signal with synchronization time marks for aligning the dithering change, thereby shifting the null area in the region covered by the base station.