What is a smart antenna

Smart antenna is a kind of bidirectional antenna installed in the base station, which obtains directivity through a set of fixed antenna units with programmable electronic phase relation, and simultaneously obtains the directional characteristic of each link between the base station and the mobile station.

The principle of the smart antenna is to direct the radio signal to the specific direction, generate the spatial directional beam, so that the antenna main beam alignment to the user signal arrival direction of DOA (directionofarrinal), side lobe or 0-notch interference signal to the direction of arrival, Achieve the goal of fully efficient use of mobile subscriber signals and remove or suppress interference signals. At the same time, smart antenna technology utilizes the difference of signal space between each mobile user, and receives and emits multiple mobile user signals on the same channel through array antenna technology without interfering with each other, which makes the use of radio frequency spectrum and signal transmission more effective. Without increasing system complexity, the use of smart antennas can meet the needs of service quality and network expansion.

At present, most of the antenna of mobile communication base station is omni-direction antenna, when paging mobile communication user is looking for the whole cell in covering, the power and signal intensity of the antenna are mostly consumed in transmission. The new type of antenna adopts the method of partition paging, which divides the beam of antenna into several partitions of different angles. Smart antennas are developed on the concept of a partitioned transmission path (sectorized transmission path). Smart antennas Use advanced technology, the radio signal to the specific direction, so that the use of radio frequency spectrum and signal transmission more effective. The advanced technologies used are mainly beam conversion technology (switched beam technology) and adaptive Space Digital processing (adaptive spatial digital processing).

The smart antenna using beam conversion technology is to send multiple beams to the user direction on the basis of partition, to track mobile users according to the signal strength of each beam, and to convert the beam to the mobile user. It is also called a beam-converting antenna (switched beam antennas). Dividing the beam into many narrow beams can enhance the signal and restrain the interference, which can reduce the interference and improve the quality of service.

The smart antenna system for beam conversion is mainly used to simulate mobile communication. The intelligent antenna used in digital mobile communication network is adaptive digital processing technology.

The smart antenna of adaptive digital processing technology uses the algorithm of digital signal processing to measure the signal intensity of different beam, so it can change the transmission power concentration of the antenna dynamically. The application of spatial processing technology (spatial processing technology) can enhance the signal capability and enable multiple users to use a channel together.