Patent ID: 11894010
Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
Field: Computer technology (Electrical engineering)
Classification: CPC G  H | IPC G

Claim 12:
13. The signal processing device according to claim 10 or 11, wherein
the instantaneous beamformer is equivalent to a sum of a constant multiple of the estimated steering vector and a product of a block matrix corresponding to an orthogonal complement of the estimated steering vector and a modified instantaneous beamformer, and
the estimation unit includes:
an initial beamformer application unit that acquires an initial beamformer output of the first time interval that is based on the estimated steering vector of the first time interval and the frequency-divided observation signals belonging to the first time interval;
the suppression unit that acquires the estimation target signals of the first time interval that is based on the initial beamformer output of the first time interval, the estimated steering vector of the first time interval and the frequency-divided observation signal, and the convolutional beamformer of the second time interval that is further in the past than the first time interval;
an adaptive gain estimation unit that acquires an adaptive gain of the first time interval that is based on an inverse matrix of the weighted modified space-time covariance matrix of the second time interval, and the estimated steering vector of the first time interval, the frequency-divided observation signals and the power or estimated power of the target signals;
a matrix estimation unit that acquires an inverse matrix of the weighted modified space-time covariance matrix of the first time interval that is based on the adaptive gain of the first time interval, the estimated steering vector of the first time interval and the frequency-divided observation signals, and the inverse matrix of the weighted modified space-time covariance matrix of the second time interval; and
the convolutional beamformer estimation unit that acquires the convolutional beamformer of the first time interval that is based on the adaptive gain of the first time interval, the estimation signals of the first time interval, and the convolutional beamformer of the second time interval.