Path loss of radio wave propagation
Path Loss of Receiver In Heavy Rain
Specify the transmitter and the receiver sites.
tx = txsite('Name','MathWorks Apple Hill', ... 'Latitude',42.3001,'Longitude',-71.3504, ... 'TransmitterFrequency', 2.5e9); rx = rxsite('Name','Fenway Park', ... 'Latitude',42.3467,'Longitude',-71.0972);
Create the propagation model for heavy rainfall rate.
pm = propagationModel('rain','RainRate',50)
pm = Rain with properties: RainRate: 50 Tilt: 0
Calculate the pathloss at the receiver using the rain propagation model.
pl = pathloss(pm,rx,tx)
pl = 127.3208
rx — Receiver site
Receiver site, specified as a
rxsite object. You can
use array inputs to specify multiple sites.
tx — Transmitter site
Transmitter site, specified as a
txsite object. You can
use array inputs to specify multiple sites.
Specify optional pairs of arguments as
the argument name and
Value is the corresponding value.
Name-value arguments must appear after other arguments, but the order of the
pairs does not matter.
Before R2021a, use commas to separate each name and value, and enclose
Name in quotes.
Map — Map for visualization or surface data
siteviewer object |
triangulation object | string scalar | character vector
Map for visualization or surface data, specified as a
triangulation object, a string scalar, or a character vector.
Valid and default values depend on the coordinate system.
|Coordinate System||Valid map values||Default map value|
a Alignment of boundaries and region labels are a presentation of the feature provided by the data vendors and do not imply endorsement by MathWorks®.
In most cases, if you specify this argument as a value other than a
"none", then you must also specify an
pl — Path loss
scalar | M-by-N arrays
Path loss, returned as a scalar or M-by-N cell arrays containing a row vector of path loss values in decibels. M is the number of TX sites and N is the number of RX sites.
Path loss is computed along the shortest path through space connecting the transmitter and receiver antenna centers.
For terrain propagation models, path loss is computed using terrain
elevation profile that is computed at sample locations on the great circle
path between the transmitter and the receiver. If
siteviewer object with buildings specified, the
terrain elevation is adjusted to include the height of the buildings.
info — Information corresponding to each propagation path
M-by-N structure array | M-by-N cell array containing vector
of structures in each cell
Information corresponding to each propagation path, returned as a M-by-N cell array containing vector of structures in each cell for ray tracing propagation models and M-by-N structure array for all other propagation models. The field and values for the structures are:
PropagationDistance— Total distance of propagation path returned as a double scalar in meters.
AngleOfDeparture— Angle of departure of signal from transmitter site antenna returned as a 2-by-1 double vector of azimuth and elevation angles in degrees.
AngleOfArrival— Angle of arrival of signal at receiver site antenna returned as a 2-by-1 double vector of azimuth and elevation angles in degrees.
NumReflections— Number of reflections undergone by signal along propagation path, returned specified as
2. This field and value is only for ray tracing propagation models.
Angle values in this structure are defined using the local East-North-Up
coordinate system of the antenna when
geographic. Angle values in this structure are
defined using global Cartesian coordinate system when
CoordinateSystem is set to
cartesian. Azimuth angle is measured either from east
'geographic') or from the global x-axis around the
global z-axis (when
'cartesian'). Elevation angle is
measured from the horizontal (or X-Y) plane to the x-axis of the antenna in
the range -90 to 90.
Version HistoryIntroduced in R2019b
R2023a: Ray tracing models discard paths based on path loss
Ray tracing propagation models discard propagation paths based on path loss
thresholds. By default, when you specify the
argument as a
object, the propagation model discards paths that are more than 40 dB weaker than
the strongest path.
As a result, the
pathloss function can return different
values in R2023a compared to previous releases. To avoid discarding propagation
paths based on relative path loss thresholds, set the
MaxRelativePathLoss property of the ray tracing object to
R2022b: Ray tracing models using SBR method find paths with exact geometric accuracy
Ray tracing models that find propagation paths by using the shooting and bouncing rays (SBR) method correct the results so that the geometric accuracy of each path is exact, using single-precision floating-point computations. In previous releases, the paths have approximate geometric accuracy.
As a result, when you use a ray tracing model as input to the
pathloss function, the function can return different
results than in previous releases.