Research Of Co-Channel Interference Based On Medical Communication Standards Of Internet Of Things

The population explosion and the shortage of medical resources limit the economic and social development of China. However, to some degree, the Wireless Body Area Network (WBAN) can solve this problem. Although there are some of relatively maturity standards in the whole search fields, China still has no corresponding one for the reason of the difference of the band division and the medical&health approach. To solve this problem, we proposed an OQPSK physical layer scheme based on spread spectrum relied on the IEEE802.15.4n working group. The main works of this paper were as follows:(1) This paper proposed a physical layer modulation scheme based on laboratory issues by referring IEEE802.15.4g/IEEE802.15.4c, and then analyzed the performance of the physical layer under the Gaussian channel and Rayleigh channel. The simulation results showed the good performance of the physical layer, so this proposal is feasible.(2) This paper also analyzed the physical layer performance in the interference background, such as China Mobile Multimedia Broadcasting (CMMB), walkie-talkie, wireless microphone, remote control devices, IEEE802.15.6device, the results showed that the physical layer could suppress the effect of interference to some extent.(3) In view of transmitting vital information, high requirements on reliability were needed for wireless body area network, so this paper also studied the interference suppression. Firstly, this paper proposed a new frame detection algorithm based on twice delayed-autocorrelation to solve the problem that the frame detection had high false alarm rates, the algorithm exhibited better performance in narrowband and wideband interference. Secondly, this paper presented an interference avoiding method based on the MAC layer. The main idea was to distinguish channel using priority by making full use of the priori information that the interference parameters were known, and interference detection method during the non active period. These mechanisms reduce the network overhead and design complexity.The results of this study can provide important technical reference for standards development of wireless body area network standard.