| 1. |
- Berg, Magnus, et al.
(författare)
-
A combined on-line PCA-ICA algorithm for blind source separation
- 2005
-
Konferensbidrag (refereegranskat)abstract
- In this paper, we introduce and investigate a method combining principle component analysis (PCA) and independent component analysis (ICA) for blind source separation (BSS). A recursive method for the PCA is applied to meet the demands of a real-time application, and likewise a modified on-line version of the information maximization principle is used. The combined PCA-ICA algorithm, first reduces the dimension of the problem and then separates the signals. Evaluation of the proposed algorithm in a real room shows superior noise suppression capabilities compared to the use of PCA or ICA individually. The proposed algorithm achieves an impressive noise suppression/separation of up to 14 dB with only two microphones. Most importantly this is achieved with negligible distortion of the recovered signal. © 2005 IEEE.
|
|
| 2. |
- Claesson, Ingvar, et al.
(författare)
-
A Multi-DSP implementation of a Broadband Adaptive Beamformer for use in a Hands-free Mobile Radio Telephone
- 1991
-
Ingår i: IEEE Transactions on Vehicular Technology. - New York : Institute of electrical and electronics engineers. - 0018-9545. ; 40:1, s. 194-202
-
Tidskriftsartikel (refereegranskat)abstract
- An implementation of a broadband adaptive array on a multiprocessor digital signal processing (DSP) system for use in a hands-free mobile radio telephone is described. This implementation of a five-microphone adaptive Griffiths-Jim array can handle FIR filters with up to 128 taps behind each microphone at a sampling rate of 8 kHz. The filter structure makes it possible to combine an adaptive array with a noise canceler. The near-field problem has been solved by using focusing, a speech-controlled adaptive algorithm, and a short hourglass. Preliminary measurements indicate a considerable potential for this technique in hands-free mobile telephony. The array gives a 20-30-dB suppression of a broadband jammer covering 300-1100 Hz, even with three reflecting walls surrounding the microphone.
|
|
| 3. |
- Claesson, Ingvar, et al.
(författare)
-
A Spatial Filtering Approach to Robust Adaptive Beamforming
- 1992
-
Ingår i: IEEE Transactions on Antennas and Propagation. - New York : Institute of electrical and electronics engineers. - 0018-926X. ; 40:9, s. 1093-1096
-
Tidskriftsartikel (refereegranskat)abstract
- This communication treats the problem of controlling the superresolution in adaptive beamformers. A straightforward method is presented that works for both narrow-band and broad-band arrays. The method is based on forming the blocking matrix in a general sidelobe canceller (GSC) structure using a spatial FIR filter. The suppression of this spatial filter and the implicit noise of the leaky (LMS) algorithm together determine the beamformer.
|
|
| 4. |
|
|
| 5. |
|
|
| 6. |
- Claesson, Ingvar, et al.
(författare)
-
Car Performance of an Adaptive Microphone Array
- 1992
-
Konferensbidrag (refereegranskat)abstract
- Hands free input of mobile telephones is often almost impossible due to the noise situation in the car and the channel quality. The authors present a method to enhance the quality using an adaptive microphone array. Measurements show an improvement of the input with approximately 10 dB. Tape results are available for subjective evaluation.
|
|
| 7. |
|
|
| 8. |
|
|
| 9. |
|
|
| 10. |
- Claesson, Ingvar, et al.
(författare)
-
Wiener Solution for the Broadband Griffiths-Jim Beamformers
- 1990
-
Konferensbidrag (refereegranskat)abstract
- The problem of finding the Wiener filters for a wideband adaptive beamformer is treated. Explicit expressions are given for the filters and the error power spectrum in the frequency domain. The expressions are simple to program and make it possible to investigate superresolution for wideband signals and to determine sufficient lengths of finite-impulse-response filters in adaptive arrays.
|
|
