Performance analysis of various IEEE 802.15.4 PHYs under Rayleigh fading channel

IEEE 802.15.4 is a set of standards that specify the physical layer (PHY) and medium access layer (MAC) of Zigbee wireless network protocol. Zigbee protocol is predominantly applied in applications that require low power consumption, low data rate and ultra-low complexity. IEEE 802.15.4 specifies three frequency bands of operation: 868 MHz, 915 MHz and the 2.4GHz unlicensed industrial, scientific and medical (ISM) band. In the present paper, we discuss implementation of the physical layer at 858,915MHz and 2.4GHz bands using Direct Sequence Spread Spectrum (DSSS) technique and also analyze its performance under Rayleigh fading channel, whose characteristics are exhibited by real-time channels. Implementation part includes the design of transceiver and performance analysis is done by comparing bit error rate (BER) of the transceiver with signal to noise ratio (SNR).