User aware distributed antenna system

#Distributed antenna system (DAS) is a method used mainly in cellular systems to cover indoor areas (buildings, malls, stadiums, etc.) or in some cases outdoor areas. The system is based on two main parts. The first one is the cellular base-station (macro base station, small cell, etc.). The second part includes taking the base-station interface (or aggregation of few base-stations) and distributing it to multiple antennas deployed in the given area, e.g., an indoor area of a mall. In some DAS systems the distribution is done directly to the antennas and in other DAS systems it is done via remote radio units (RRUs, or simply RUs).

#There is a wide range of DAS systems, but most can be characterized as either passive DAS or active DAS. FIG. 1 depicts an example of a prior art passive distributed antenna system (DAS) 100. FIG. 2 depicts an example of a prior art active distributed antenna system (DAS) 200.

#In the passive DAS 100 shown in FIG. 1, the RF output/input of one or several cellular base-stations is combined and then carried by a combination of cables and splitters to the antennas. A passive DAS 100 typically uses passive RF components such as coaxial cable, splitters, taps and couplers to distribute signal inside a building. In active DAS shown in FIG. 2, the combined function is done by special unit (head-end or HE) and then distributed in digital or analog form to distributed remote radio units (RRUs), which are sometimes referred to as remote RF units or remote radioheads. Each remote unit RU is connected to one or several antennas. An active DAS, such as 200, typically converts the analog radio frequency transmissions from the signal source to a digital signal for distribution. A master unit (e.g., HE) typically performs this analog-to-digital conversion. The master unit may digitize the signal from a single carrier or multiple carriers. Once converted, the DAS typically transmits the digital signal over fiber optic or Ethernet cables to remote radio units (RRUs) that convert the signal back to an analog signal.

#The drawings are of illustrative embodiments. They do not illustrate all embodiments. Other embodiments may be used in addition or instead. Details that may be apparent or unnecessary may be omitted to save space or for more effective illustration. Some embodiments may be practiced with additional components or steps and/or without all of the components or steps that are illustrated. When the same numeral appears in different drawings, it refers to the same or like components or steps.

#FIG. 1 depicts an example of a prior art passive distributed antenna system (DAS).

#FIG. 2 depicts an example of a prior art active distributed antenna system (DAS).

#Illustrative embodiments are now described. Other embodiments may be used in addition or instead. Details that may be apparent or unnecessary may be omitted to save space or for a more effective presentation. Some embodiments may be practiced with additional components or steps and/or without all of the components or steps that are described.

#Embodiments of the present disclosure include DAS systems and/or methods that are aware of cellular-user/antenna relationships. The DAS systems and/or methods include or use one or more User Aware (UA) Units that provide the functionality of knowing (or, knowledge of) which cellular user(s) each antenna can communicate with (and vice versa). The UA Units function to gather information about the reception in each antenna in order to identify the cellular users that the respective antenna can communicate with or best communicate with compared to other cellular users.

#FIG. 3 depicts an exemplary embodiment of a User Aware (UA) distributed antenna system (DAS) 300, in accordance with the present disclosure. US DAS 300 includes a base station 310, a number of remote radio units 320 (RU-1 to RU-9), which are shown connected, respectively, to a number of antennas 330 (ANT-1 to ANT-9). Two instances of representative user equipment (UE 1 and UE 2) are shown. A User Aware (UA) Unit 340 is included in the DAS system 300, and enables the DAS system 300 to be aware of which cellular user or users (UE) is/are communicating with each antenna (or RU). A distribution network 350 is shown connecting the base station 310, the radio units 320, and the antennas 330.