Two steps you should consider when you want to buy Xbee module.
1. Range of send/receive signal of Xbee module.
Xbee module can be separated obviously into two series in term of “The range of send and receive signal”.
The word “PRO” was used to indicate the difference between each series. Xbee series without word “PRO”
is designed for short-range wireless communication (around 100 metre when use outdoor) with power output between 1 – 2 mW.
Example of Xbee module in this series is XBee 802.15.4 .
Xbee series with word “PRO” is more powerful. It’s designed for long-range communication (up to 1600 metre when use outdoor) and
have power output between 50-60 mW. Example of Xbee module in this series is XBee-PRO 802.15.4 .
However, the practical range that Xbee can operate may depend on many factors such as the environment of system , type of antenna , type of obstacles , etc.
Xbee use frequency band at 2.4 Ghz that is the same as Bluetooth or Wireless Lan so when you use Xbee in the environment that Bluetooth or Wireless Lan exists,
signal of Xbee may be disturbed by these devices and cause the data loss during communication.
The 2.4 Ghz frequency band is arranged into the Microwave band (S Band). One important characteristic of Microwave is
“The power of transmission is highest when placement of sender and receiver device is in line-of-sight (no obstacles between them)”. Therefore , the Xbee “PRO” series that
have the range of communication up to 1.6 Km is only in case that you place the devices in line-of-sight with the best quality of antenna and no interference signal, other
conditions will reduce the signal strength and make the range that Xbee can communicate to be less than 1.6 Km.
2. Series of Xbee
Xbee has two series , Series1 and Series2. The difference between Series1 and Series2 can be concluded as following
2.1 Series2 is designed to use in mesh network while Series1 cannot be used in mesh network (Series1 is suitable for point-to-point or point-to-multipoint task).
2.2 They use different chipset , different firmware and different protocols so you can’t use Xbee Series1 together with Series2 in the same time.
2.3 Zigbee protocol is only supported on Series2 and no longer supported on Series1.
2.4 Series2 can be separated into 2 sub-series , Znet2.5 and ZB. The difference between Series2 Znet2.5 and Series2 ZB is
“Series2 (ZB) can upgrade firmware over-the-air while Series2 (Znet2.5) and Series1 can upgrade firmware with X-CTU via serial communication only”
Please see the article on ladyada or faludi website for more information about upgrading Xbee module.
So before you buy Xbee module , you should consider about the application and environment of your system first.
For example, in agriculture , suppose you have 10 Acre strawberry garden and you want to apply wireless sensor network (WSN) technology in order to measure the tempurature
in each cultivated area , in this case you should select the Xbee “PRO” series because your area is wider than the range that normal Xbee series can operate.
Otherwise if you want to build the WSN network that consist of many sensor nodes (Xbee node) and data communication in your network is very complicate,
you should select to use Mesh Network instead of Star Network (I will talk about Xbee Topology in the next article) .
The next article will be about Xbee Topology , comparison of each antenna type that affect to the range of signal transmission , interference signal and