Beginner Question in Wireless

Hello Guys
I have good experience in uC but not in wireless systems
I want to make a project that connect about 10 to 20 uC boards to a single master uC and exchange data between the slaves and the master for around 50 meters distance between them.
what is the best way to connect and trnasfer data between such things
is there some already finished cheap transmiters and reciever in the market that can directly connect to microcontrollers or its better to do it by my self
Please need any links or helps on how to design such systems.
Thank you

For already made modules, www.radiometrix.com . If you want transceiver chips, go to www.chipcon.com or www.nvlsi.no , but there you will have to make some RF work (it is easy, there are a lot of helpfull app notes).

/pisoiu

I used some of the Chipcon IC's (CC1000) a while back and they are simple to use yet powerfull (16level FIFO, CRC, Manchester, Whitening etc. are standard features) and I got ranges of 100m+ Indoors with LOS, without approx 75m

Cheers
Slayer

Is it possible to achieve a multi slave communicatin gwith one master with such chips or they r point to point chip and what kind of protocol to use?

ZeleC