Backscatter Pedestrian
A model of the backscatter pattern of pedestrian signals.
Description
The Backscatter Pedestrian unit simulates the monostatic reflection of unpolarised electromagnetic signals from a walking pedestrian. The walking pedestrian model coordinates the movement of 16 body segments to simulate natural movement. The model also simulates the radar reflectivity of each body segment. From this model, you can derive the position and velocity of each segment, as well as the overall backscatter pattern as the body moves.
Ports
Input
#
X
—
random radar signals
`complex matrix M by 16'
Details
The radar input signals at each body segment, given as a complex matrix by . - Is the number of samples in the signal. See Body Segment Indices for the column representing the incident signal on each body segment.
| Data types |
|
| Complex numbers support |
Yes |
#
Ang
—
input signal direction
real matrix 2 by 16
Details
The directions of the incident signal to the body segments given as a real matrix by . Each column Ang specifies the direction of the incident signal as a pair [AzimuthAngle;ElevationAngle].
See Body Segment Indices for the column representing the incident signal at each body segment.
| Data types |
|
| Complex numbers support |
No |
#
AngH
—
pedestrian direction
scalar
Details
The direction of pedestrian movement, specified as a scalar. The direction is measured in the plane from the axis towards the axis .
| Data types |
|
| Complex numbers support |
No |
Output
#
Y
—
combined reflected radar signals
`complex vector M at 1'
Details
Combined reflected radar signals returned as a complex vector by columns. equals the same number of samples as in the input signal X.
| Data types |
|
| Complex numbers support |
Yes |
#
Pos
—
body segment positions
real matrix 3 by 16
Details
The positions of body segments, returned as a real matrix by . Each column represents the Cartesian position, [x;y;z], of one of the 16 body segments.
See Body Segment Indices for the column representing the incident signal on each body segment.
| Data types |
|
| Complex numbers support |
No |
#
Vel
—
velocity of body segments
real matrix 3 by 16
Details
The velocity of body segments, returned as a real matrix by . Each column represents the Cartesian velocity, [vx;vy;vz], of one of the 16 body segments.
See Body Segment Indices for the column representing the incident signal on each body segment.
| Data types |
|
| Complex numbers support |
No |
#
Ax
—
orientation of body segments
real array 3 by 3 by 16
Details
Orientation axes of body segments, returned as a real array by by . Each page represents the 3 by 3 orientation axes of one of the 16 body segments.
See Body Segment Indexes for a page representing the incident signal on each body segment.
| Data types |
|
| Complex numbers support |
No |
Parameters
Main
#
Pedestrian height (m) —
pedestrian height
Real number
Details
Pedestrian height given as a positive scalar.
| Default value |
|
| Program usage name |
|
| Tunable |
No |
| Evaluatable |
Yes |
#
Pedestrian walking speed (m/s) —
walking speed
Real number
Details
Pedestrian walking speed, specified as a non-negative scalar. The maximum speed must not be more than 1.4 times the pedestrian height specified in the Pedestrian height (m) parameters.
| Default value |
|
| Program usage name |
|
| Tunable |
No |
| Evaluatable |
Yes |
#
Propagation speed (m/s) —
signal propagation speed
Real number
Details
The propagation velocity of a signal as a real positive scalar.
| Default value |
|
| Program usage name |
|
| Tunable |
No |
| Evaluatable |
Yes |
#
Signal carrier frequency (Hz) —
signal carrier frequency
Real number
Details
The carrier frequency of a narrowband incident signal in the form of a positive real scalar.
| Default value |
|
| Program usage name |
|
| Tunable |
No |
| Evaluatable |
Yes |
#
Initial position (m) —
pedestrian starting position
Vector of real numbers
Details
The initial position of the pedestrian given as a real vector on in the form [x;y;z].
| Default value |
|
| Program usage name |
|
| Tunable |
No |
| Evaluatable |
Yes |
#
Initial heading direction (deg) —
pedestrian’s initial direction of travel
Real number
Details
The initial direction of pedestrian movement, specified as a scalar. The direction is measured in -plane from -axis towards -axis.
| Default value |
|
| Program usage name |
|
| Tunable |
No |
| Evaluatable |
Yes |
Additional Info
*Body segment indices
Body segment indexes identify which columns in ports X, Ang, Pos and Vel contain data for a particular body segment. Body segment indexes identify which page in port Ax contains data for a particular body segment. For example, column 3 of page X contains sample data for the left tibia. Column 3 of port Ang contains the angle of arrival of the signal at the left tibia.
Body segment |
Index |
|
Left leg |
1 |
|
Right leg |
2 |
|
Left tibia |
3 |
|
Right tibia |
4 |
|
Left upper leg |
5 |
|
Right upper leg |
6 |
|
Left thigh |
7 |
|
Right thigh |
8 |
|
Left lower arm |
9 |
|
Lower right arm |
10 |
|
Left upper arm |
11 |
|
Right upper arm |
12 |
|
Left shoulder |
13 |
|
Right shoulder |
14 |
|
Head |
15 |
|
Torso |
16 |
|
