multiple robot communications

Other Hardware Robotics
1

I am looking for something, that seems to be maybe 3 things at once.

  1. Wireless 2-way comm's between a PC and a remote uC, probably something in the 324/644/1284 family. Or uC under human control to a remote uC.
  2. Must be able to have 25-30 pairs of these things communicating in the same room without interfering with each other.
  3. 2.4GHz, Bluetooth, Wifi, other RF, don't really care, will be in a classroom type environment, so 40-50ft range.
  4. Looking for inexpensive.

There's too many choices out there, I am having a hard time finding some search terms to filter it down some.
Anyone have experience with anything?

2

They need to communicate with each other or just with a master control pc?

3

Multiple PC/uC pairs. No master PC. No uC to uC comm's.
Same as if there were 25 tethered PC/uC setups.

4

How do these look?
Laird Technologym, all $22 at Mouser. I don't quite grasp the subtleties between them.
Ah - interface type seems to be the differentiator:

http://www.mouser.com/ds/2/223/LWS-DS-BTM410-411%200412-201563.pdf
Bluetooth / 802.15.1 Modules Class2 v2.1+EDR AT Data, Int Ant
Host Interface: UART Supports CTS, RTS, DTR, DSR, DCD and RI

http://www.mouser.com/ds/2/223/btm420.421-187315.pdf
Bluetooth / 802.15.1 Modules Class2 v2.1+EDR HCI Data, Int Ant
Host Interface: USB Qualified to USB v 1.1. Compliant with USB 2.0 Data signalling requirements.

http://www.mouser.com/ds/2/223/LWS-DS-BTM430-431%200412-195524.pdf
Bluetooth / 802.15.1 Modules Class2 v2.0+EDR, AT Data, IntAnt, BISMII
Host Interface UART Supports CTS, RTS, DTR, DSR, DCD and RI

All are Class 2, V2.0 or V2.1 Bluetooth, antenna built in, good range.

So assuming V2.1 is better than V2.0, and UART will connect to uC's Rx/Tx, looks like BTM-411 would be the way to go?

The Laird Technologies Wireless M2M Solutions BTM411 Bluetooth AT Data Module is designed to add robust, short range Bluetooth data connectivity to a variety of products. Laird Technologies Wireless M2M Solutions BTM411 AT Data Modules are based on the market leading Cambridge Silicon Radio BC04 chipset and provide exceptional low power consumption with outstanding range. The BTM411 supports the latest Bluetooth Version 2.1 Specification and is ideal for a variety of applications, including wirelessly connected medical devices The DVK-BTM411 Bluetooth® Module Kit lets you test and design applications incorporating the BTM411 module. The Laird Technologies Wireless M2M Solutions DVK-BTM411 kit features an integrated antenna and allows developers to add robust, short range Bluetooth data connectivity to their products.

CSR BC04 chipset data?
http://www.csr.com/products/49/bluecore4-pc-rom

Thought I saw 79 channels somewhere, should allow 25 pairs to connect up without interference?

5

I'd choose NRF24 based 2.4 GHz, compare to BT there is 10x price difference:

16 chanels, if I'm not mistaken. Do you really need all pair on the air simultaneously? Or short burst in TDMA-way would be o'k?