Performance evaluation and channel modeling of IEEE 802.15.4c in urban scenarios

摘要

The IEEE802.15.4 is a low-bit-rate wireless communicate standard that enables global inter-connectivity and inter-operability amongst Wireless Personal Area Network (WPAN) transceivers from different manufacturers. It is also considered as the PHY and MAC technology for Wireless Sensor Networks, which can be widely used for sensing, gathering and operating information in future smart cities. In Jan. 2009, the 802.15.4c amendment was approved to address the Chinese regulatory changes which have opened new bands for Wireless PAN using within China. However, the urban environments' impacts over its performance in the new band are still not clear. We demonstrate the viability of using IEEE 802.15.4c in urban scenarios by a series of real field experiments and result analysis. Results show that at 4dBm transmission power over 780MHz channel and with typical antenna setups, the effective transmission range is 200 meters in open scenario, 60 and 40 meters in light and heavy traffic scenarios respectively. We also show that the performance is not affected evidently by the mobility of transceivers up to the speed of 80 km/h. The most important performance factors are the availability of line-of-sight between sender and receiver in urban scenarios. We also use the famous Rappaport channel model for field experimental data fitting, and show that the model is valid even with moving massive reflectors. The empirical data and model fitting will benefit upper layer protocol design based on 802.15.4c in China in the future.