New generation aids for laryngectomy patients

• Published in: The Journal of the Acoustical Society of America 2006-11, Vol.120 (5_Supplement), p.3351-3351
• Main Authors: Czyzewski, Andrzej, Odya, Piotr, Kostek, Bozena
• Format: Article
• Language: English
• ISSN: 0001-4966; 1520-8524
• DOI: 10.1121/1.4781417

The artificial larynx has many disadvantages. The produced speech is monotonous and sounds artificially. In addition, produced speech intelligibility is usually poor. The major problem is a background noise caused by the device. In fact, the artificial larynx is only a simple vibrator, a construction of which has been almost unchanged since the 1950s. The aim of the presented project is to design a new generation of devices for laryngectomy patients. There are two different approaches to solve this task. The first one focuses on the artificial larynx. Some major improvements in the construction of the device might be easily introduced. Hence, the artificial larynx engineered was equipped with a digital processor and an amplifier. The spectral subtraction algorithm for noise reduction was used. In this method, an average signal spectrum and average noise spectrum are estimated and subtracted from each other, thus average signal-to-noise ratio (SNR) is improved. The main problem to be solved was that both the noise and the speech signal have the same excitation source and consequently are strongly correlated for voiced sounds. The second approach uses a PDA (portable digital assistant) to generate synthetic speech. The proposed new generation devices helping laryngectomy patients are presented in the paper.