Hi,

I am designing a RF project, I do not know what is the differenec betwteen
a  and  b.

   a .  microcontroller  or any UART + RF

   b.      microcontroller + modem chip (fx919) + RF

the project is car security system, communicate cars in the city. sometime
for car finding system.


  There are many wireless products  now( running at 9600 bps), what  is
the modem engine for.

Can I use microcontroller uart  +  RF , to  performce the job?.


Best regards,


James Chu