ZigBee is a specification for a suite of
high level communication protocols used to create personal area networks built from small,
low-power digital radios. ZigBee is based on an IEEE
802.15 standard. Though low-powered, ZigBee devices often transmit data
over longer distances by passing data through intermediate devices to reach
more distant ones, creating a mesh
network; i.e., a network with no centralized control or high-power
transmitter/receiver able to reach all of the networked devices. The
decentralized nature of such wireless ad hoc networks make them suitable
for applications where a central node can't be relied upon.
ZigBee is used in applications that
require a low data rate, long battery life, and secure networking. ZigBee has a
defined rate of 250 kbit/s, best suited for periodic or intermittent data or a
single signal transmission from a sensor or input device. Applications include
wireless light switches, electrical meters with in-home-displays, traffic
management systems, and other consumer and industrial equipment that requires
short-range wireless transfer of data at relatively low rates. The technology
defined by the ZigBee specification is intended to be simpler and less
expensive than other WPANs, such as Bluetooth or Wi-Fi.
ZigBee networks are secured by 128 bit symmetric encryption keys. In home automation
applications, transmission distances range from 10 to 100 meters line-of-sight, depending on power output
and environmental characteristics.
FEATURES OF ZIGBEE MODULE
2394-2507MHz
transceiver
•
DSSS
transceiver
•
250kbps data
rate, 2 MChip/s chip rate
•
O-QPSK with
half sine pulse shaping modulation
•
Very low
current consumption
RX
(receiving frame, -50 dBm): 18.5 mA
RX
(waiting for frame): 22.3 mA
TX
(+5 dBm output power): 33.6 mA
TX
(0 dBm output power): 25.8 mA
•
Three flexible
power modes for reduced power consumption
•
Low power fully
static CMOS design
•
Very good
sensitivity (-98dBm)
•
High adjacent
channel rejection (49 dB)
•
High alternate
channel rejection (54 dB)
•
On chip VCO,
LNA, PA and filters.
•
Low supply
voltage (1.8 - 3.8 V)
•
Programmable
output power up to +5 dBm
• I/Q direct conversion transceiver
