Xbee 900Mhz Telemetry System

Xbee is a radio module based on the Zigbee protocol that we use for our telemetry system. A comparison between all the models is found on Sparkfun and on the Xbee website

Specs and Documentation

Mini-USB Adapters: 

https://www.parallax.com/product/32400

XBee-Pro 900 XSC S3B (XBP9B-0DPST-001)

• RF Data Rate: 10-20 kbps
• Frequency: 900Mhz
• Power: Up to 250mW (software selectable)
• Range: 610m Indoor, 14km with dipole antenna, 45km with high gain antenna
• Supply Voltage: 2.4 to 3.6 VDC
• Product Link: https://www.parallax.com/product/32411
• Datasheet: https://cdn.sparkfun.com/datasheets/Wireless/Zigbee/90002173_N.pdf or Xbee900ProS3BDatasheet.pdf

XBee-PRO S1 802.15.4 extended-range module w/ RPSMA connector (XBP24-ASI-001)

• RF Data Rate: 250 kbps
• Frequency: 2.4Ghz
• Power: 60mW
• Range: 100m indoor, 1.6km outdoor
• Supply Voltage: 2.8 - 3.4VDC
• Retrieved from: https://www.digi.com/pdf/ds_xbeemultipointmodules.pdf
• Datasheet: https://cdn-shop.adafruit.com/datasheets/Xbee+series+1+DS.pdf or XbeeSeries1Datasheet.pdf

Antennas:

• Smaller ground antenna (for testing):
  • Gain: 2dBi
  • RPSMA female connector
  • Link: https://www.parallax.com/product/32410
• Larger Antenna (on plane)
  • Dont know model, or gain, or even if its a 900Mhz 
    
    

Shortened Datasheets

The Xbee documentation is pretty long, however if you're just trying to understand the communication structure, the following two datasheets should provide most of the information you'll need. The first file describes the AT commands the module uses. The AT commands are used to configure each module, and it is what software like XCTU uses. The second file describes the API packet structure that the PicPilot sends to the Xbee's for various functionalities (like sending a TX packet, getting RSSI, etc).

Configuring the Modules with XCTU

The best way to configure the Xbee modules is with XCTU, which is a GUI made by Digi.

After downloading the software, the module you're configuring needs to be plugged in to an Xbee mini-USB adapter. You cannot

use the Xbee breakout used for the Picpilot to configure the modules from your PC, unless you configure remote AT commands, which it too complicated to describe.

All of the modules should be configured to connect via UART at 115200 baud/s, 8N1 (1 stop bit, no parity). If this doesn't work initially, try re-plugging in the usb adapter from your PC. Note that by

default the modules come pre-configured to connect at 9600baud/s, so if the Xbee was just bought, use that.