84 results about "Antenna spacing" patented technology

The invention is directed to a method and system for equalizing the signal losses over cable runs in a Distributed Antenna System (DAS). In a DAS, two or more antennae are connected to the system by cable runs that can vary widely in length. As a result, the signal loss over a given cable run can also vary widely which can impact the design and deployment of the DAS and reduce antenna spacing. In addition, for a broadband DAS that supports many frequency bands or ranges using a common antenna unit, the signal losses vary with respect to frequency further making it difficult to equalize the cable losses. According to one embodiment of the invention, the method and system provide for measuring and adjusting the signal losses of each cable run to be a predefined value. According to another embodiment of the invention, the DAS can include a hybrid passive-active antenna unit which includes a frequency multiplexer that separates the signal into frequency bands or ranges that are connected to an antenna element associated with a particular frequency band or range. Where a single frequency band needs to be amplified (or attenuated), a single band amplification block (SBAB) can be inserted in the connection between the frequency multiplexer and the antenna element to amplify (or attenuate) the desired frequency band. Where more than one frequency band need to be amplified (or attenuated), a multiband amplification block (MBAB) can be inserted in the connection between the frequency multiplexer and the appropriate antenna element to amplify (or attenuate) the desired frequency bands.

In a MIMO communication system that includes a transmitter and a receiver and forms line-of-sight orthogonal channels between the transmitter-side transmitting antenna and the receiver-side receiving antenna, the MIMO communication system is provided between the transmitting antenna and the receiving antenna with an optimum antenna-to-antenna spacing shortening unit to shorten an optimum antenna-to-antenna spacing by changing the phase rotation of a carrier wave used for directly opposed waves between opposed antennas, and the phase rotation of a carrier wave used for intersecting waves between oblique antennas in such a manner that the amount by which one of the phase rotations changes is different from that by which the other phase rotation changes.

An integrated MIMO antenna system is described wherein multiple antennas are fabricated on a single substrate. Antenna spacing and alignment is enhanced and controlled to a finer degree than with conventional discrete antenna fabrication techniques. Rotation of one or multiple antennas in relation to the other antennas in the system can be performed to within the accuracy of current photo-etching techniques. Metalized traces can be designed and etched on the single substrate and positioned between antenna elements to enhance inter-element isolation. The integrated MIMO antenna system can be fabricated on flexible printed circuit (FPC) material, or can be fabricated on rigid metallized substrate such as common FR4 materials. Portions of one or multiple antenna elements can be photo-etched on opposite sides of the substrate to provide an additional degree of freedom in terms of antenna placement, spacing, and rotation angle.

A wireless communication system supporting improved performance in a sparse multi-path environment is provided that uses spatially reconfigurable arrays. The system includes a first device and a second device. The first device includes a plurality of antennas and a processor operably coupled to the plurality of antennas. The plurality of antennas are adapted to transmit a first signal toward a the second device and to receive a second signal from the second device. The processor is configured to determine an antenna spacing between the plurality of antennas based on an estimated number of spatial degrees of freedom and an estimated operating signal-to-noise ratio. The second device includes a receiver adapted to receive the first signal from the first device, a transmitter adapted to transmit the second signal toward the first device, and a processor. The processor estimates the number of spatial degrees of freedom and the operating signal-to-noise ratio from the received first signal.