Root MUSIC direction of arrival (DOA) estimator for ULA and UCA
The RootMUSICEstimator
object implements the
root multiple signal classification (rootMUSIC) direction of arrival
estimator for uniform linear arrays (ULA) and uniform circular arrays
(UCA). When a uniform circular array is used, the algorithm transforms
the input to a ULAlike structure using the phase mode
excitation technique [2].
To estimate the direction of arrival (DOA):
Define and set up your DOA estimator. See Construction.
Call step
to estimate the DOA
according to the properties of phased.RootMUSICEstimator
.
The behavior of step
is specific to each object in
the toolbox.
Note
Starting in R2016b, instead of using the step
method
to perform the operation defined by the System object™, you can
call the object with arguments, as if it were a function. For example, y
= step(obj,x)
and y = obj(x)
perform
equivalent operations.
H = phased.RootMUSICEstimator
creates a
root MUSIC DOA estimator System object, H
.
The object estimates the signal's direction of arrival using the root
MUSIC algorithm with a uniform linear array (ULA).
H = phased.RootMUSICEstimator(
creates
object, Name
,Value
)H
, with each specified property Name
set to the specified Value. You can specify additional namevalue
pair arguments in any order as (Name1
,Value1
,...,NameN
,ValueN
).

Sensor array System object Sensor array specified as a System object. The sensor array
must be a Default: 

Signal propagation speed Specify the propagation speed of the signal, in meters per second, as a positive scalar. You can specify this property as single or double precision. Default: Speed of light 

System operating frequency Specify the operating frequency of the system in hertz as a positive scalar. The default value corresponds to 300 MHz. You can specify this property as single or double precision. Default: 

Perform forwardbackward averaging Set this property to Default: 

Spatial smoothing The averaging number used by spatial smoothing to estimate the covariance matrix, specified as a strictly positive integer. Each additional smoothing value handles one additional coherent source, but reduces the effective number of elements by one. The maximum value of this property is M2. For a ULA, M is the number of sensors. For a UCA, M is the size of the internal ULAlike array structure defined by the phase mode excitation technique. The default value of zero indicates that no spatial smoothing is employed. You can specify this property as single or double precision. Default: 

Source of number of signals Specify the source of the number of signals as one of When spatial smoothing is employed on a UCA, you cannot set
the Default: 

Method to estimate number of signals Specify the method to estimate the number of signals as one
of Default: 

Number of signals Specify the number of signals as a positive integer scalar. This property applies when you set
the Default: 
step  Perform DOA estimation 
Common to All System Objects  

release  Allow System object property value changes 
[1] Van Trees, H. Optimum Array Processing. New York: WileyInterscience, 2002.
[2] Mathews, C.P., Zoltowski, M.D., "Eigenstructure techniques for 2D angle estimation with uniform circular arrays." IEEE Transactions on Signal Processing, vol. 42, No. 9, pp. 23952407, Sept. 1994.
broadside2az
 phased.RootWSFEstimator
 rootmusicdoa
 sensorcov
 spsmooth