Hi, The MIMO tag is really misleading. What the 'MIMO' routers with ordinary clients does for you is realizing a MISO (Multiple Input, Single Output) channel and provide antenna diversity. One can view this as multiple antennas (2 or 3) at the router will send multiple streams to the client. The client with one antenna will recieve them all and since we have created redundancy since the data is in the air in several copies we have better shot at decoding it. Then how data is mapped onto the antenna streams can be more or less clever. To send the data in three copies is one shot, but better performance is achieved with some coding where the data is cleverly spread over all antennas, but not necessarily in identical copies.
Even better can be achieved if you can recieve more of the wireless energy that's in the air, i.e. more recieving antennas, and now we get something like a MIMO channel multiple antennas transmitting and recieving. If we're lucky we could view this as multiple independent paths over pairwise antennas. Reality plays us some tricks, and we essentially never are that lucky. We could however help luck a bit by informing the transmitter about how the reciever see things on its side and adapt the transmission accordingly. Now we're getting where draft-N is aiming. However, the most certain benefit from multiple antennas without too much clever processing is mutliple antennas on the receiver side (compare how much better a laptop with an internal WLAN and two recieving antennas in the lid performs compared to a PCMCIA card with only one antenna). I do not know too much about the slim antenna configuration - I guess it has some sort of patch antenna, but more antennas on the router side would then at least improve the uplink to the router - something that the slim has only slight benefit from. End of class ... /Fredrik -- fgunnars ------------------------------------------------------------------------ fgunnars's Profile: http://forums.slimdevices.com/member.php?userid=12216 View this thread: http://forums.slimdevices.com/showthread.php?t=37330 _______________________________________________ discuss mailing list [email protected] http://lists.slimdevices.com/lists/listinfo/discuss
