To investigate interference, and how to avoid it, by high-frequency electromagnetic fields (EMFs) of Global System for Mobile Communications (GSM) mobile phone with communication between cardiac rhythm management devices (CRMs) and programmers, a combined in vivo and in vitro testing was conducted. During in vivo testing, GSM mobile phones interfered with CRM-programmer communication in 33 of 65 subjects tested (50.8%). Losing ventricle sensing was representative in this study. In terms of clinical symptoms, only 4 subjects (0.6%) felt dizzy during testing. CRM-programmer communication recovered upon termination of mobile phone communication. During in vitro testing, electromagnetic interference by high-frequency (700-950 MHz) EMFs reproducibly occurred in duplicate testing in 18 of 20 CRMs (90%). During each interference, the pacing pulse signal on the programmer would suddenly disappear while the synchronous signal was normal on the amplifier-oscilloscope. Simulation analysis showed that interference by radiofrequency emitting devices with CRM-programmer communication may be attributed to factors including materials, excitation source distance, and implant depth. Results suggested that patients implanted with CRMs should not be restricted from using GSM mobile phones; however, CRMs should be kept away from high-frequency EMFs of GSM mobile phone during programming.

ZigBee technology is mainly used in short distance, low power consumption, low rate, low complexity of equipments for data transmission. When image has a large amount of data, it should be processed firstly, and then transmitted. This essay makes a research on healthy care system, using CMOS camera to get image and compress image. Then, the compressed image is transferred to ARM processor, and divided into data packets according to the requirement of the ZigBee network transmission. Finally, the image is transferred to control center and displayed. After the final test, this system can get images to meet the requirements, which has some practical values.