Wireless communications in time-variant ad hoc networks is very challenging. The increasing demand for mobile multimedia and safety applications in time-variant environments requires new concepts for the development of such wireless systems.

Time-variant scenarios can be found in several environments:
  • Vehicle-to-vehicle or vehicle-to-infrastructure communication used for driving assistance systems
  • Driver assistance systems such as adaptive cruise control (ACC)
  • MESH and sensor networks in time-variant scenarios
  • Wi-Fi hotspots in railroad stations, airports or city centers
  • Stations and underground stations with moving trains
  • Airports with moving airplanes
  • Elevators inside buildings

The main difference in such applications compared to the classical network planning is the time variance of these scenarios. The locations of transmitters, receivers, and obstacles are time-variant. These effects influence the propagation and lead to time-variant channel impulse responses.

The WinProp software package offers a time-variant module which allows the definition of time-variant behavior and the prediction of spatial channel impulse responses considering the time-variant effects such as Slow Fading. The steps for a successful simulation of a time-variant scenario are the following: 

Table 1.  Steps for execution of a successful time-variant scenario.
Step WinProp Component
Generation of vector database describing the environment and the vehicles WallMan
Assignment of time-variant properties to the vehicles WallMan
Setting up a project with the parameters of the simulation ProMan
Computation of prediction ProMan
Visualization of result ProMan