Anadili Türkçe olan konuşmacılar tarafından söylenen NATO fonetik alfabesinin akustik analizi: El ve gırtlak mikrofonlarının karşılaştırması

Year 2026, Volume: 15 Issue: 1, 1 - 1

Julio Cesar Velazquez Garcia , Selim Aras

Abstract

Bu pilot çalışma, anadili Türkçe olan konuşmacıların NATO fonetik alfabesini telaffuz ederken el tipi ve boğaz mikrofonlarıyla kaydedilen konuşma sinyallerinin karşılaştırmalı akustik analizini sunmaktadır. Toplam 2.080 ses örneği toplanmış ve ses etkinliği tespiti (VAD), gürültü azaltma ve sessizlik kırpma adımlarını içeren bir ön işleme sürecinden geçirilmiştir. Süre, ortalama karekök (RMS) enerjisi, sıfır geçiş oranı (ZCR) ve saniye başına sıfır geçiş yoğunluğu gibi akustik ölçümler çıkarılmıştır. Non-parametrik testler, mikrofon türleri arasında anlamlı farklar olduğunu ortaya koymuştur: El tipi mikrofon daha yüksek enerji ve zamansal kararlılık sağlarken, boğaz mikrofonu daha düşük enerji ancak daha yüksek spektral karmaşıklık göstermiştir. Bazı konuşmacılarda ses üretiminde gecikme ve artikülasyon asimetrileri gözlemlenmiştir. Bulgular, mikrofon türünün fonetik yapı ve sinyal kalitesini etkilediğini ve gürültülü ortamlarda otomatik konuşma tanıma (ASR) sistemleri için önemli çıkarımlar sunduğunu göstermektedir. Bu çalışma, gerçek dünya koşullarına uygun çok kanallı ASR sistemleri için temel oluşturmaktadır.

Keywords

NATO fonetik alfabesi , Gırtlak mikrofonu , El tipi mikrofon , Konuşma sinyali analizi , ASR sağlamlığı.

Acoustic analysis of the NATO phonetic alphabet spoken by native Turkish speakers: A comparison of handheld and throat microphones

Abstract

This pilot study presents a comparative acoustic analysis of speech signals recorded with handheld and throat microphones during the pronunciation of the NATO phonetic alphabet by native Turkish speakers. A total of 2,080 voice samples were collected and preprocessed using voice activity detection (VAD), noise reduction, and silence trimming. Acoustic metrics; duration, root mean square (RMS) energy, zero-crossing rate (ZCR), and zero-crossing density, were extracted. Non-parametric tests revealed significant differences between microphone types: the handheld device yielded higher energy and stability, while the throat microphone showed lower energy but higher spectral complexity. Results also indicated phonatory delay and articulation asymmetries in some speakers. The findings suggest that microphone type affects phonetic structure and signal quality, with implications for automatic speech recognition (ASR) systems in noisy environments. Notably, the throat microphone increased zero-crossing density due to internal vibration sensitivity. This study lays the groundwork for multichannel ASR systems designed for real-world acoustic variability.

Keywords

NATO phonetic alphabet , Throat microphone , Handheld microphone , Speech signal analysis , ASR robustness

Ethical Statement

This study was conducted with the approval of the Ethics Committee for Social and Human Sciences Research of Ondokuz Mayıs University. The approval was granted on 29 November 2024 under the decision number 2024-1118. The research involved voice recordings and interviews carried out as part of a master’s thesis titled “Machine Learning-Based Analysis and Resolution of Multilingual Pronunciation Issues in the NATO Phonetic Alphabet”, under the supervision of Dr. Öğr. Üyesi Selim Aras.

Thanks

This study was conducted with the approval of the Ethics Committee for Social and Human Sciences Research of Ondokuz Mayıs University. The approval was granted on 29 November 2024 under the decision number 2024-1118. The research involved voice recordings and interviews carried out as part of a master’s thesis titled “Machine Learning-Based Analysis and Resolution of Multilingual Pronunciation Issues in the NATO Phonetic Alphabet”, under the supervision of Dr. Öğr. Üyesi Selim Aras.

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