Network planning tools can automate iterative process required for manual planning. In the past few years, there were few tools. Some of them can plan indoor and outdoor networks, or at least include a few outdoor cells for evaluation of interference or transfer between systems.
When selecting the indoor network planning tool, set the following important questions. He has the appropriate RF distribution model? As the required input entered into the tool? The relationship between the input and the RF model is weak for the aggregate models, but is becoming increasingly important – requiring more effort – for Ray run or (even worse) ray tracing model.
Most indoor network planning tools (for picocells) use distribution models that can be classified as follows:
• Empirical models. They believe only one spatial relationships between one receiver with data, building and one transmitter.
• Semiempirical models. They are consistent with the brightly-Keenan model. In addition to this simple remote section of modeling, closed planning tool may include a simulation of diffraction, which would mimic the vertical and horizontal effects. The vertical plane of diffraction, is generally seen in the open or close the network planning tool, is of limited use in the room, because it simulates an entire floor at once. On the other hand, the horizontal plane diffraction useful indoors to evaluate the effect of a wall and the holes (i.e., doors and windows).
• Deterministic models. These consider propagation medium (waveguide effects corridors, tunnels, etc.) and physical characteristics of septum (permittivity, conductivity and reflection) to accurately estimate a signal received at the receiver. These models can be divided into 2-D or 3-D models and raytracing simplified model of the dominant path. Ray tracing model can solve the various possible paths from transmitter to receiver for individual path loss prediction.
Outcome prediction at each point of the combined signal summing all multipath components reach the specified location. Predictions can also be explained by the diffraction effects around the corners, which is of particular importance to outdoor conditions selenium. Because of computer calculations required, deterministic models will take longer than the empirical models do.
Relatively high accuracy deterministic models, nevertheless need to be balanced with the required accuracy that the required power (both as a building material and its characteristics) and relative slowness model . Deterministic is faster way to a true 3-D ray tracing. It basically selects only the most appropriate ways of all those defined in 3-D ray tracing, and then determines the attenuation distribution wall penetration, reflection and diffraction losses.
The level of effort required to calculate the accurate determination of the building, together with a long prediction specifically ray tracing model still do not recommend the use of such wide planning tools.