Hello,
We participate in a Brazilian project which aims to send experiment into the stratosphere (> 35 km) and make the telemetry data. Will be only necessary communication in one direction, ie, it will not be necessary to send soil data until the experiment.
We are studying the possibility of using the XBee modules to perform the communication. For it would like some information about them:
What are the modules (besides the XBee XSC, XBee 868 Xtend and 900 MHz) that have a range exceeding 35 km?
It is necessary that the two modules are the same model to have communication between them?
The "transmit power" is a specification that we should only consider to choose the transmitter module or that interferes with signal reception?
Which parameter should be considered to choose the receiver module?
The modules: XBee XSC, XBee 868 and 900 MHz Xtend has license for use in Brazil?
Thanks! 