Beam tilt is used in

radio Radio is the technology of signaling and communicating using radio waves. Radio waves are electromagnetic waves of frequency between 30 hertz (Hz) and 300 gigahertz (GHz). They are generated by an electronic device called a transmi ...

to aim the main lobe of the

vertical plane In astronomy, geography, and related sciences and contexts, a '' direction'' or ''plane'' passing by a given point is said to be vertical if it contains the local gravity direction at that point. Conversely, a direction or plane is said to be hor ...

radiation pattern In the field of antenna design the term radiation pattern (or antenna pattern or far-field pattern) refers to the ''directional'' (angular) dependence of the strength of the radio waves from the antenna or other source.Constantine A. Balanis: “A ...

of an antenna below (or above) the horizontal plane. The simplest way is mechanical beam tilt, where the antenna is physically mounted in such a manner as to lower the angle of the signal on one side. However, this also raises it on the other side, making it useful in only very limited situations. More common is electrical beam tilt, where the

phasing A phaser is an electronic sound processor used to filter a signal, and it has a series of troughs in its frequency-attenutation graph. The position (in Hz) of the peaks and troughs are typically modulated by an internal low-frequency oscil ...

between antenna elements is tweaked to make the signal go down (usually) in all directions. This is extremely useful when the antenna is at a very high point, and the edge of the signal is likely to miss the target (broadcast audience, cellphone users, etc.) entirely. With electrical tilting, front and back lobes tilt in the same direction. For example, an electrical downtilt will make both the front lobe and the back lobe tilt down. This is the property used in the above example where the signal is pointed down in all directions. On the contrary, mechanical downtilting will make the front lobe tilt down and the back lobe tilt up. In almost all practical cases, antennas are only tilted down – though tilting up is technically possible. The use of purely electrical tilt with no mechanical tilt is an attractive choice for aesthetic reasons which are very important for operators seeking acceptance of integrated antennas in visible locations. In GSM and UMTS cellular networks, mechanical tilt is almost always fixed whereas electrical tilt can be controlled using remote actuators and position sensors, thus reducing operating expenses. Remote electrical tilt is abbreviated as RET and it is part of the Antenna Interface Standards Group's open specification for the control interface of antenna devices. Occasionally, mechanical and electrical tilt will be used together in order to create greater beam tilt in one direction than the other, mainly to accommodate unusual

terrain Terrain or relief (also topographical relief) involves the vertical and horizontal dimensions of land surface. The term bathymetry is used to describe underwater relief, while hypsometry studies terrain relative to sea level. The Latin wo ...

. Along with

null fill Null fill in radio engineering is used in radio antenna systems which are located on mountains or tall towers, to prevent too much of the signal from overshooting the nearest part of intended coverage area. Phasing is used between antenna elements ...

, beam tilt is the essential parameter controlling the focus of

communication Communication (from la, communicare, meaning "to share" or "to be in relation with") is usually defined as the transmission of information. The term may also refer to the message communicated through such transmissions or the field of inqui ...

s, and together they can create almost infinite combinations of 3-D

s for any situation.

Beam tilt optimization

Beam tilt optimization is a network optimization technique used in mobile networks aiming at controlling the inclination of the vertical tilt angle of the antenna in order to optimize a set of network performance indicators. Different studies in beam tilt optimization focus on Coverage-Capacity Optimization (CCO), for which the goal is to control the beam tilt in order to jointly optimize the radio coverage and capacity in the network cells and reduce interference from neighbouring cells. There exists mainly two types of approaches to beam tilt optimization: # Rule-based algorithms: consist of optimization strategies based on domain knowledge and control theory, and mainly based on the optimization of utility metrics, or threshold-based policies employing Fuzzy Logic (FL) to model representative network performance indicators. # Data-driven algorithms : consist of optimization strategies based on the use learning techniques based on the availability of network data (e.g. Contextual Bandit (CB) techniques), or by directly interacting with the environment (e.g.

Reinforcement Learning Reinforcement learning (RL) is an area of machine learning concerned with how intelligent agents ought to take actions in an environment in order to maximize the notion of cumulative reward. Reinforcement learning is one of three basic machine ...

(RL) techniques )

References

{{Analogue TV transmitter topics Antennas Broadcast engineering