Wireless InSite^® applies physics-based propagation models to site-specific predictions in rural, urban and indoor environments, and to viewing and analyzing the predictions. With only a few steps it is possible to import data for buildings, foliage, floor plans and terrain, define the antennas, specify the transmitter and receiver locations, select the desired output, and run the calculations.

The Project view displays all the currently loaded building data, terrain data, and transmitter and receiver sets. After the calculations have been run, most of InSite's predictions can also be displayed in the Project view. Several viewing modes are available: 2D or 3D, wire frame or solid body, and in 3D mode: orthographic or perspective. The user has full control over zooming, rotating and panning in all viewing modes.

When buildings are located close together it may be difficult to get a clear view of an individual building. The primary purpose of the Selection view is to offer an unobstructed view of an individual building or small group of buildings. The Selection view retains all the viewing modes and controls possessed by the Project view.

InSite's Project hierarchy provides a convenient means to navigate within the input and output file of a project. Each level in the hierarchy can be expanded to view the underlying levels. Selecting an item and right-clicking can be used to access the properties and other actions that are available for it. The Project hierarchy is especially useful for viewing and plotting output.

The Calculation log window records all information generated while performing simulations, including the time and date the calculation started/finished, its current progress as well as the elapsed time.

InSite employs robust ray tracing algorithms which can be applied to complex urban environments. However, excessive detail can slow down the computations considerably and in some cases even produces less accurate results. InSite's building editing tools allow the user to eliminate unnecessary detail manually if desired. But InSite's automated preprocessor can also do this for you, cleaning up the data and putting it in the form required by the propagation models. The figure on the right shows a typical example of the "simplification" of a building performed by the preprocessor.

A different material can be assigned to each building or each building face, if desired. The default material types include metal, concrete, brick, wood, glass and several types of ground. Instead of selecting a particular material, you may choose whether the reflection and transmission coefficients are evaluated for a dielectric half-space, a one-layer wall of finite thickness, or a two-layer wall, and then set the constitutive parameters and thickness for each layer. You can also define materials with constant reflection and transmission coefficients and set the color and display properties of each material.  All materials that are used by features in the project are shown in a legend on the right side of the project view for fast and easy identification.

InSite makes placing transmitters and receivers easy. Points, routes, grids, arcs and spheres can be defined graphically, or their locations can be read from data files. Elevations can be set either with respect to the terrain or to sea level. Antennas are assigned to each set along with the operating frequency and bandwidth. The position and elevation of the Tx/Rx locations can easily be modified using InSite's Tx/Rx editing tools. Each of the Tx/Rx sets can be designated as active or inactive, determining whether or not it will be used in the next calculation. This eliminates the need to add or delete locations from the data files when making a series of calculations for different transmitter-receiver combinations.

InSite offers several ways to specify the radiation pattern and polarization of an antenna. The omnidirectional and generic dipole patterns are preprogrammed. The direction of the main beam and the rotation about the main beam can be specified, as can a noise figure, reflection efficiency factor, and a cable loss factor. In the antennas properties window the gain pattern can be viewed using a specified waveform in vertical, horizontal, left-hand circular and right-hand circular polarizations as well as the total gain.

An antenna can be created to represent an array of similar elements.  Wireless InSite uses the amplitude, phase, and relative location of each element to create a combined antenna pattern that can be assigned to a single transmitter or receiver point.

In addition to vertical and horizontal polarization, left-hand circular and right-hand circular polarizations are for isotropic, omni-directional and helical antennas. Circularly polarized antennas can be imported using Wireless InSite's user-defined format. They can also be imported from far zone cut plane data generated by Remcom's XFdtd^® software. The effect of circular polarization is calculated by means of the relative phase between the theta and phi components of the electric field.

To facilitate the orientation of transmitter and receiver antennas, rotated antenna patterns can be displayed in the Project view. The display of antenna patterns is enabled for each transmitter and receiver set in the Tx/Rx Properties window. In addition to antenna patterns, the final orientation of antenna patterns can be visualized through the display of a set of orthogonal control vectors. Antenna rotations are specified by applying rotations to these vectors.

Wireless InSite allows users to define the following waveform pulse shapes: Gaussian/Gaussian derivative, Blackman, Chirp, Hamming, Hanning, Tukey, raised-cosine, root raised-cosine, and sinusoid. In addition, InSite also provides a user-defined waveform type.

Wireless InSite contains user-defined antenna, material, and waveform databases. Once added to the database, commonly used components are accessible to all projects and save the user the trouble of entering the same information repeatedly.

To aid in creating projects and referencing output, Wireless InSite includes the capability to overlay terrain with geo-referenced raster images. Images can be used to help place transmitters and receivers correctly in a project. Common types of geo-referenced images include scanned maps, aerial photographs and satellite photos. Images can also be imported that represent floor plans to allow for easy creation of that type of feature. 

The calculation for a project can be split up so that sections run on separate processors.  This can be done so that one calculation is run for each transmitter set or receiver set and the priority of the processes can be set allowing the user to more fully commit their PC to the calculation or reduce its effect on other running applications.  After the calculation finished a special job will run to create the consolidated output types such as selecting the strongest transmitter and the total power of all transmitters at a given receiver point.

Wireless InSite can display both ray paths and signal coverage for indoor propagation. Wireless InSite includes propagation paths through doors and windows and reflection from and transmission through walls. A more detailed example of applying Wireless InSite to an indoor geometry is shown in the Examples Section.

Wireless InSite is unique in providing the capability to make propagation predictions for indoor-outdoor signal paths and even indoor-outdoor-indoor paths for transmitter/receivers located in different buildings. Wireless InSite includes propagation through windows and transmissions through walls, and even multi-path involving other buildings.

Wireless InSite requires full three-dimensional building data. Accurate data for a large number of cities is now provided by a growing number of sources. This data is available in a number of formats including AutoCAD's dxf format. InSite is able to read dxf files and convert the data to InSite's "city" file format. Once the dxf file is read, material properties can quickly be assigned to each building. InSite also allows for conforming the buildings to the underlying terrain. Building data can be in latitude/longitude, UTM or Cartesian coordinates.

Wireless InSite 's building editing tools can be used to create new buildings or modify existing buildings.

Wireless InSite can now import city data in raster format and convert it to vector format for use will all propagation models. By interpreting values in the raster data as heights, the raster-to-vector converter can detect regions of similar height and form buildings by extruding these regions to the ground. The file formats currently supported include ARC ASCII Grid and Portable Gray Map (.PGM).

Wireless InSite is able to read DTED files and USGS DEM files. Terrain can either be imported as a rectilinear region or as a radial profile between two geographic points.  This last method is useful for keeping the complexity of the terrain low when running the Vertical Plane or Moving Window FDTD models.  Material properties can be assigned to the terrain during importation.

Irregular terrain is modeled using an arbitrary number of triangular facets. In many cases this terrain would be read from DTED and USGS DEM files. However, InSite's terrain editing tools also enable the user to create a new terrain or modify an existing terrain. The editing tool allows you to set the elevation of the nodes on the triangular mesh, to move the nodes, and to create additional nodes. For terrain profiles different tools are provided for moving the points of the profile and changing the material to be used between them.

Wireless InSite can make calculations for virtually any indoor floor plan. Floor plans may be read into Wireless InSite from CAD files such as dxf or by using the Wireless InSite Floor Plan Editor. The Floor Plan Editor allows placement of doors and windows. Walls which do not reach the ceiling, such as used in office cubicles, can be modeled by placing a window at the top of a wall. Floor plans may be edited and combined to form more complicated structures. An image of an existing floor plan can be added to a project which will appear in the editor to assist in its construction.

The Wireless InSite floor plan editor can stack floor plans to form complete buildings. The stacked floor plans may be different to allow for differences between floors. The floor and ceiling materials may be defined to include propagation between floors.

Wireless InSite is capable of importing antenna pattern data from NSMA, Odyssey, MSI planet, and XFdtd files. InSite also has its own antenna pattern file format through which users can create user-defined antenna patterns.

Geo-referenced foliage information can be imported from data in the Global Land Coverage Characteristics (GLCC) database, which is available for download from the Land Processes Distributed Active Archive Center (LPDAAC). This database has information on Seasonal Land Cover Region (SLCR), which has a 1x1 km resolution.

The foliage editor allows users to create new foliage groups and edit existing groups. Foliage features are defined by drawing a footprint and specifying a height. The foliage can be fit to the contour of the underlying terrain, or it may be created with flat top and bottom faces at specified heights, independent of the terrain. Materials specific to modeling bio-physical vegetation are provided for this type of feature.

Information from the transportation layer of the Vector Map (VMAP) database can be used to create routes of transmitter or receiver points.

The output from the calculation can be further analyzed to produce bit-error rate information.  A communication system can be created that allows the user to specify the transmitter and receivers that are of interest and specify the parameters to use for the calculation including the interference source, jamming power, modulation scheme and the outage threshold.

These types of plots are provided to allow for a more detailed analysis of the output generated by the calculation engine.

Study areas serve several purposes. First, they can be used to select a region of the building database and then to limit all computations to the buildings, terrain features and Rx/Tx locations within the study area. Different propagation models can be applied within each study area. Second, as an organizational tool they keep predictions made with different parameters separate from each other. The user can create as many study areas as desired.

InSite produces a large number of point-to-multipoint predictions, including received power, path loss, time of arrival, direction of arrival, impulse response, SNR, and delay spread. These results can be viewed using InSite's line plotting tools or as color-coded displays overlaid on the feature data. All predictions are made with full frequency, polarization and antenna pattern data taken into account. Data for multiple transmitters is also available, including C/I, C/I+N, and strongest base station to receiver.

InSite's physics-based propagation models predict the paths by which energy travels from the transmitting to the receiving antenna. InSite's graphical interface makes it easy to view direction-of-arrival and impulse response for each transmitter-receiver link.

Data for multiple transmitters are also available, including C/I, C/I+N, and strongest base to receiver. All predictions are made with full frequency, polarization, and antenna pattern data taken into account.

InSite's physics-based propagation models are able to predict the paths by which energy travels from the transmitting to the receiving antenna. The graphical interface makes it easy to view and interpret these results.

Color-coded displays are frequently a very useful analysis tool, but in many cases the best way of representing data is a line plot. All output is written to ASCII files with descriptive headers using an easy-to-understand format. All output can be plotted with InSite's line plotting tools. Plots can be saved and reloaded at a later time. Plots can be added and deleted. Measurements or data generated from other software products can also be imported into InSite.

Output filters isolate ray paths with specific interactions. For instance, a filter can be created for rays that reflect off of features, but do not have diffractions. Rays meeting this condition will be sorted into a separate branch in the output tree. The filter allows the user to identify what objects are the major contributors to the final power received by a set of receivers.

Several ray-based propagation models aimed at different environments have been incorporated into Wireless InSite. All are based on a hybrid SBR/GTD approach developed by Remcom. The Shooting and Bouncing Ray (SBR) is employed at the start of the calculation to determine the geometrical ray paths through the building and terrain geometry. The SBR method has been implemented with robust ray tracing techniques that impose few limitations on the complexity of the building or terrain features. Once the propagation paths have been found, the amplitudes are evaluated using the Geometrical Theory of Diffraction (GTD).

The Urban Canyon FDTD model is intended for high-rise urban environments where the transmitting and receiving antennas are located close to the ground relative to the building heights. For these situations, buildings can be modeled as being infinitely tall, and the interactions with the buildings are entirely determined by the 2D ground level perimeters, or footprints, of the buildings. Urban Canyon FDTD simulates radio propagation by using the finite-difference time-domain (FDTD) method to directly solve Maxwell's equations.

Wireless InSite can extract arbitrary vertical planes from three-dimensional terrain data to perform fast and accurate 2-D calculations. These can be performed for arbitrarily chosen transmitter and receiver sets. Wireless InSite is accurate because it computes both amplitude and phase of the electric fields for all the most essential paths (up to three diffractions and an arbitrary number of reflections) from the transmitter to the receiver and sums these to determine the total electric field and other derived quantities.

The Moving Window FDTD model is based on the 2D finite-difference time-domain method. This model is used to simulated propagation of radio waves at UHF and VHF frequencies over irregular terrain. A vertical plane passing through the transmitter and receivers location defines the 2D geometry. Modeling propagation over terrain typically involves long distances. The amount of computer memory and time required to perform FDTD on the entire path is often prohibitive. Moving Window FDTD takes advantage of the fact that the radio pulse width is limited in spatial extent, and only creates computation grid wide enough to include the radio pulse. As the pulse propagates over the terrain, the computational mesh is also moved so that the pulse is always contained in the grid. This allows the method to only calculate field values in regions where the field is nonzero. Since this method solves Maxwell's equations directly, it is a full-wave model that includes all relevant physical processes associated with radio wave propagation in the 2D environment.

Until relatively recently, site-specific predictions were not possible given realistic limits on the amount of both human and computer time that could be expended. Instead of site-specific methods, empirical methods were applied (e.g., Okumura-Hata, Walfisch-Ikegami, etc.). These are not specific to a particular site, but classify sites in categories, such as dense urban, suburban, rural, etc. Path loss is estimated based on these classifications and on the distance between the transmitter and receiver antennas. These methods obviously cannot provide predictions for specific paths, but they are useful for providing area coverage statistics, and have the advantage of being very fast.