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A low-cost, portable, high-throughput wireless sensor system for phonocardiography applications.

Sa-Ngasoongsong A, Kunthong J, Sarangan V, Cai X, Bukkapatnam ST - Sensors (Basel) (2012)

Bottom Line: The experimental results of sensor signal analysis using several signal characterization techniques suggest that this wireless sensor system can capture both fundamental heart sounds (S1 and S2), and is also capable of capturing abnormal heart sounds (S3 and S4) and heart murmurs without aliasing.The results of a denoising application using Wavelet Transform show that the undesirable noises of sensor signals in the surrounding environment can be reduced dramatically.The exercising experiment results also show that this proposed wireless PCG system can capture heart sounds over different heart conditions simulated by varying heart rates of six subjects over a range of 60-180 Hz through exercise testing.

View Article: PubMed Central - PubMed

Affiliation: School of Industrial Engineering & Management, Oklahoma State University, Stillwater, OK 74078, USA. akkarap@okstate.edu

ABSTRACT
This paper presents the design and testing of a wireless sensor system developed using a Microchip PICDEM developer kit to acquire and monitor human heart sounds for phonocardiography applications. This system can serve as a cost-effective option to the recent developments in wireless phonocardiography sensors that have primarily focused on Bluetooth technology. This wireless sensor system has been designed and developed in-house using off-the-shelf components and open source software for remote and mobile applications. The small form factor (3.75 cm × 5 cm × 1 cm), high throughput (6,000 Hz data streaming rate), and low cost ($13 per unit for a 1,000 unit batch) of this wireless sensor system make it particularly attractive for phonocardiography and other sensing applications. The experimental results of sensor signal analysis using several signal characterization techniques suggest that this wireless sensor system can capture both fundamental heart sounds (S1 and S2), and is also capable of capturing abnormal heart sounds (S3 and S4) and heart murmurs without aliasing. The results of a denoising application using Wavelet Transform show that the undesirable noises of sensor signals in the surrounding environment can be reduced dramatically. The exercising experiment results also show that this proposed wireless PCG system can capture heart sounds over different heart conditions simulated by varying heart rates of six subjects over a range of 60-180 Hz through exercise testing.

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Related in: MedlinePlus

Packaging Data Samples with Compression.
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f7-sensors-12-10851: Packaging Data Samples with Compression.

Mentions: As shown in Figure 7, the first sample (say S1) to be loaded in each packet is always given the original real estate of two bytes. The second sample (S2) is loaded into the packet not in its original form, but in a differential form: i.e., in byte 3 of the packet, information pertaining to S2 is loaded as S2−S1; sample S3 is loaded into byte 4 of the packet as S3−S2; and so on. The lowest seven bits of byte i, 1 < i ≤ 96 in the packet, are used to represent the magnitude of the difference Si−1–Si−2, while the highest bit is used to indicate the direction of the difference (positive or negative). It is easy to see that, when the macro tag receives the first sample and the subsequent differences, it can easily reconstruct all the samples.


A low-cost, portable, high-throughput wireless sensor system for phonocardiography applications.

Sa-Ngasoongsong A, Kunthong J, Sarangan V, Cai X, Bukkapatnam ST - Sensors (Basel) (2012)

Packaging Data Samples with Compression.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3472861&req=5

f7-sensors-12-10851: Packaging Data Samples with Compression.
Mentions: As shown in Figure 7, the first sample (say S1) to be loaded in each packet is always given the original real estate of two bytes. The second sample (S2) is loaded into the packet not in its original form, but in a differential form: i.e., in byte 3 of the packet, information pertaining to S2 is loaded as S2−S1; sample S3 is loaded into byte 4 of the packet as S3−S2; and so on. The lowest seven bits of byte i, 1 < i ≤ 96 in the packet, are used to represent the magnitude of the difference Si−1–Si−2, while the highest bit is used to indicate the direction of the difference (positive or negative). It is easy to see that, when the macro tag receives the first sample and the subsequent differences, it can easily reconstruct all the samples.

Bottom Line: The experimental results of sensor signal analysis using several signal characterization techniques suggest that this wireless sensor system can capture both fundamental heart sounds (S1 and S2), and is also capable of capturing abnormal heart sounds (S3 and S4) and heart murmurs without aliasing.The results of a denoising application using Wavelet Transform show that the undesirable noises of sensor signals in the surrounding environment can be reduced dramatically.The exercising experiment results also show that this proposed wireless PCG system can capture heart sounds over different heart conditions simulated by varying heart rates of six subjects over a range of 60-180 Hz through exercise testing.

View Article: PubMed Central - PubMed

Affiliation: School of Industrial Engineering & Management, Oklahoma State University, Stillwater, OK 74078, USA. akkarap@okstate.edu

ABSTRACT
This paper presents the design and testing of a wireless sensor system developed using a Microchip PICDEM developer kit to acquire and monitor human heart sounds for phonocardiography applications. This system can serve as a cost-effective option to the recent developments in wireless phonocardiography sensors that have primarily focused on Bluetooth technology. This wireless sensor system has been designed and developed in-house using off-the-shelf components and open source software for remote and mobile applications. The small form factor (3.75 cm × 5 cm × 1 cm), high throughput (6,000 Hz data streaming rate), and low cost ($13 per unit for a 1,000 unit batch) of this wireless sensor system make it particularly attractive for phonocardiography and other sensing applications. The experimental results of sensor signal analysis using several signal characterization techniques suggest that this wireless sensor system can capture both fundamental heart sounds (S1 and S2), and is also capable of capturing abnormal heart sounds (S3 and S4) and heart murmurs without aliasing. The results of a denoising application using Wavelet Transform show that the undesirable noises of sensor signals in the surrounding environment can be reduced dramatically. The exercising experiment results also show that this proposed wireless PCG system can capture heart sounds over different heart conditions simulated by varying heart rates of six subjects over a range of 60-180 Hz through exercise testing.

Show MeSH
Related in: MedlinePlus