The Design and Realization of ZigBee—Wi-Fi
Wireless Gatway
Chaoli Zhou
Department of Computer Science and Technology
East China Normal University
Shanghai, China
51091201012@ecnu.cn
Jianhua Shen
Department of Computer Science and Technology
East China Normal University
Shanghai, China
jhshen@cs.ecnu.edu.cn
Abstract—The application of WSN/ZigBee is growing popularity
and how to connect WSN/ZigBee to the present standard
network seamlessly is an issue what is worth studying. In this
paper, it designs and realizes a ZigBee—Wi-Fi wireless gateway
based on STM32W108 RF chip and embedded Wi-Fi module. In
ZigBee network, wireless gateway as a sink, it receives data from
sensor nodes and interacts with them. In WLAN, wireless
gateway communicates with PC or network servers by means of
AP. Both the hardware scheme and software scheme of the
wireless gateway are introduced. Then the performance of the
wireless gateway is tested, and the result shows that it can be
used for general purposes and the performance is stable. The
wireless gateway can realize communication effectively between
ZigBee network and WLAN.
Keywords- ZigBee; Wi-Fi; wireless gateway; STM32W108
I. INTRODUCTION
A wireless sensor network (WSN) [1] consists of a number
of distributed devices using sensors to cooperatively monitor
physical or environmental conditions, such as temperature,
sound, vibration or pressure at different locations. ZigBee [2] is
a new IEEE802.15.4 standards-based, short distance, low-data-
rate and low-power consumption wireless communication
technology. Moreover, ZigBee specification has better
compatibility between versions from earliest ZigBee 1.0,
ZigBee 1.1 to ZigBee 2007/PRO. With the constantly
improving and maturing of ZigBee technology, it is widely
used in WSN [3] [4].
Wi-Fi [5] is a most successful wireless local area network
(WLAN) system that builds upon the IEEE 802.11 standards.
With the rapid development of Wi-Fi in recent years,
infrastructure facilities have been improved. What’s more, the
coverage of wireless access points (AP) has already been very
wide and the price is cheap. Usually, the bandwidth of WLAN
is higher than the bandwidth of other types of internet
connection such as ADSL, GPRS and 3G and the transmission
delay of WLAN is less than theirs.
In this paper, a small in size, low-power, low-price and
lightweight ZigBee–Wi-Fi wireless gateway is introduced. It
contains two functions. For one thing, in wireless sensor
network based on ZigBee (it is called ZigBee network for
short), terminal sensor nodes and route sensor nodes are
responsible for collecting and processing data. They will
employ ZigBee technology to communicate with wireless
gateway. The wireless gateway encapsulates the data that
received from ZigBee network according to a certain format
and transmits them to Wi-Fi module. For another, Wi-Fi
module sends data to monitoring software on PC by means of
AP. In addition, the Wi-Fi module sends commands from PC
to ZigBee network. Fig. 1 displays the system operation model.
II. H
ARDWARE DESIGN SCHEME
The hardware platform of wireless gateway is made up of
two parts: the RF chip STM32W108 [6] that integrates a 2.4
GHz, IEEE 802.15.4-compliant transceiver and 32-bit ARM®
Cortex
TM
-M3 microprocessor and EMW-380 Wi-Fi module.
The structure is demonstrated in Fig. 2.
Figure 1. The communication model between ZigBee network and WLAN.
Figure 2. The hardware structure of wireless gateway.
This work is supported in part by the Fundamental Research Funds for
the Central Universities grant 78220021 and the Development Funds of East
China Normal University grant 521Z5003.
978-1-4244-8039-5/11/$26.00 ©2011 IEEE