Optimal wavelet biosignal compression for mobile multi-purpose telemedicine

The availability of prompt and expert medical care can meaningfully improve health care services in understaffed rural or remote areas. The provision of effective emergency telemedicine and home monitoring solutions are the major fields of interest discussed in this study. Ambulances, rural health centers (RHCs) or other remote health locations, ships navigating in wide seas and airplanes at night are common examples of possible emergency sites, while critical-care telemetry and telemedicine home follow-ups are important issues of telemonitoring. In order to cover the above different growing application fields, a novel emergency telemedicine system has been developed. The system allows the transmission of vital biosignals and still images of the patient. The transmission is performed through wireless links (both GSM and satellite). Due to the low bandwidth available through these links (max. 9600 bps), data compression is required to allow real-time transmission of ECG data. A new integrated design approach for an optimal zonal wavelet-based ECG data compression (OZWC) method has been implemented, and the performance of the mobile system with compressed ECG data segments selected from the MIT-BIH arrhythmia database has been evaluated in terms of bit error rate (BER), percent root-mean-square difference (PRD) and visual clinical inspection. The optimal wavelet algorithm achieved a maximum compression ratio of 18:1 with low PRD ratios. Using this approach, the next generation of multi-purpose mobile telemedicine systems with wavelet compression techniques can be developed.