The study justify theperformance by

The study justify the
performance by PER, transmission delay and throughput.
Experiments were carried out on an open simulator. The
results of simulator shows the following: distance and centre
frequency offset between Wi-Fi-b and ZigBee are important
factors, if the distance is large enough between ZigBee and
WiFi devices (about more than 8 meters), hence the PER of
ZigBee is reduced