How do I specify the frrequency response in the look direction for the object phased.FrostBeamformer ?

The reference journal paper by Frost ("An Algorithm for Linearly Constrained Adaptive Beamforming", Proc IEEE, August 1972) which is referenced in the Matlab help, defines the constraint in Equation 11b. The FIR for the look direction is defined by the taps in array "F". In the description of phased.FrostBeamformer in Matlab help I do not see an opportunity to specify this filter response.

Answer 1

[Honglei Chen]

In phased.FrostBeamformer, the look direction response is set to 1. If you are interested in tweak the desired responses, you may want to give phased.TimeDelayLCMVBeamformer a try. You can find the reference page at

http://cn.mathworks.com/help/phased/ref/phased.timedelaylcmvbeamformer-class.html

HTH

[Roger Peterson]

Thank you for your reply. Your answer is consistent with the fact that I was not able to find an opportunity to set the look direction frequency response. According to the reference, one of the benefits of the Frost Beamformer is the ability to set the look direction frequency response. Hopefully I can still find a means to do this in the Matlab environment since my research needs this capability. Again, thank you for your answer!

[Honglei Chen]

Hi Roger, maybe I'm not being very clear. If you want to take full advantage of Frost's paper, you should use phased.TimeDelayLCMVBeamformer, where you can define F in the DesiredResponse property. The phased.FrostBeamformer is just a special case of the former.

[Roger Peterson]

Thank you for this clarification. This is what I needed.