# phased.GCCEstimator

Wideband direction of arrival estimation

## Description

The `phased.GCCEstimator`

System object™ creates a direction of arrival estimator for wideband signals. This
System object estimates the direction of arrival or time of arrival among sensor array
elements using the generalized cross-correlation with phase transform algorithm
(GCC-PHAT). The algorithm assumes that all signals propagate from a single source lying
in the array far field so the direction of arrival is the same for all sensors. The
System object first estimates the correlations between all specified sensor pairs using
GCC-PHAT and then finds the largest peak in each correlation. The peak identifies the
delay between the signals arriving at each sensor pair. Finally, a least-squares
estimate is used to derive the direction of arrival from all estimated delays.

To compute the direction of arrival for pairs of element in the array:

Define and set up a GCC-PHAT estimator System object,

`phased.GCCEstimator`

, using the Construction procedure.Call

`step`

to compute the direction of arrival of a signal using the properties of the`phased.GCCEstimator`

System object.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.

## Construction

creates a GCC
direction of arrival estimator System object, `sGCC`

= phased.GCCEstimator`sGCC`

. This object
estimates the direction of arrival or time of arrival between sensor array elements
using the GCC-PHAT algorithm.

returns a GCC direction of arrival estimator object, `sGCC`

= phased.GCCEstimator(Name,Value)`sGCC`

, with the
specified property `Name`

set to the specified
`Value`

. `Name`

must appear inside single quotes
(`''`

). You can specify several name-value pair arguments in any
order as `Name1,Value1,...,NameN,ValueN`

.

## Properties

## Methods

reset | Reset states of phased.GCCEstimator System object |

step | Estimate direction of arrival using generalized cross-correlation |

Common to All System Objects | |
---|---|

`release` | Allow System object property value changes |

## Examples

## Algorithms

## References

[1] Knapp, C. H. and G.C. Carter, “The Generalized Correlation Method
for Estimation of Time Delay.” *IEEE Transactions on Acoustics,
Speech and Signal Processing.* Vol. ASSP-24, No. 4, Aug
1976.

[2] G. C. Carter, “Coherence and Time Delay Estimation.”
*Proceedings of the IEEE.* Vol. 75, No. 2, Feb
1987.

## Extended Capabilities

## Version History

**Introduced in R2015b**

## See Also

`phased.BeamscanEstimator`

| `phased.RootMUSICEstimator`

| `gccphat`