Journal of Clinical Engineering • January/March 2003 55 PEER-REVIEW PAPER Remote Telemedicine Services by High Frequency Radio Link Anita D. Praba-Egge MD, Ph.D.; Russell S. Hummel III, MS, BME; Norman Stewart, Charles R. Doarn, MBA; and Ronald C. Merrell, MD Medical Informatics and Technology Applications Consortium Virginia Commonwealth University, Richmond, Virginia Abstract High frequency (HF) radio represents a universal, reliable method of communicating across distances. In this study, HF radio was used to transfer computerized electronic medical records of 10 fictitious patients from a remote rainforest hospital to a regional medical clinic in rural Ecuador. Transfer time using a frequency of 9.075 MHz was 15 minutes. After reaching the regional medical clinic, data were sent via telephone (modem) to Cuenca, Ecuador and Richmond, Virginia, using the Internet. The experiments described here demonstrate that HF radio and basic computers in remote health care facilities can be utilized to improve communications and comprehensive medical care in very remote areas of Ecuador. Index of terms: high frequency radio, telemedicine, electronic medical record, EMR, CLOVER, slow scan tv, Citerandes Foundation, JPEG, MITAC, remote medicine, Forward Error Correction (FEC), Adaptive Automatic Repeat Request (ARQ), Ecuador, Taisha, Macas. ting verbal messages, including patient information. Radio transmission does not require hard wire or fiber. Nor does it require line of sight or satellite relay. Radio waves can bounce from the ionosphere and reach almost any point on the planet with very low energy signals. Before the World Wide Web and fiber there was a worldwide sharing of informa- tion by HF radio transmission. Radio operators have relayed news, notices, grief, and joy. Radio Teletype (RTTY) was de- veloped by the military after 1938 as a reliable automatic means of text messaging. 6 It first appeared in use during World War II and continues to be used by a wide range of commercial users. Further advances in automatic radio text messaging appeared in the 1960’s with forward error cor- recting (FEC) transmission protocols such as SITOR, and AMTOR. 7 FEC modes allowed error free text to be transmit- ted and received even when propagation was less than op- timum or interference was present. 6 The introduction of microprocessors, data compression algorithms and digital signal processing (DSP) has further advanced the techniques of automated messaging. These modern modulation methods include PACTOR, PACTOR II, CLOVER II and CLOVER 2000: they offer automatic error- free communications under the most adverse RF conditions, including atmospheric disturbance, electrical interference Introduction Telemedicine has been defined as the practice of medi- cine using audio, visual and data communications, includ- ing the delivery of medical care, medical consultation, diag- nosis, treatment, and education as well as the transfer of medical data. 1,2 Management of medical information at a distance may date back centuries to all manner of commu- nication signals relative to patients. 3 Nascent technologies evoke telemedicine images of robotic surgery, virtual real- ity, and advanced computer equipment. High-speed tele- phone connections or wireless networks allow transfer of patient information including high-resolution images (physi- cal or radiographic findings, for example). Such specialized equipment is costly and available to only a fraction of the world’s population. Most of the earth in fact has very lim- ited access to advanced medical care or technology. Ironi- cally, these are the places whose people could benefit greatly from telemedicine through services such as medical con- sultation and access to basic medical information. In 1901, the first trans-Atlantic radio signal was sent and received using International Morse code (CW). 4 Voice trans- missions followed only a few years later in 1906. 5 Since then the radio has been used as a universal, reliable method of communicating across distances with radio waves transmit-