[Tinyos-help] Bit Error Rate for CC2420

[Philip Levis]

On Dec 4, 2006, at 3:31 AM, Rafael Marin Perez wrote:

> Hi all,
>
> I have saw a method for calculating bit error rates (BER) from  
> packet error
> rates (PER) for the CC1000 radio  in Mica RFM with SecDed encoding.
>

This isn't for the CC1000, which is part of the mica2 platform. It's  
for the mica platform, which had an RFM TR1000 radio. The CC1000 is a  
byte-level radio, while the TR1000 is a bit-level radio.


>
> But I need a method for calculating bit error rates(BER) from  
> packet error
> rates (PER) for the CC2420 radio in MicaZ or Telos with O-QPSK  
> encoding.
> Or Forward Error Correction (FEC).

This becomes difficult because of hoe the CC2420 encodes/decodes  
packets. The 802.15.4 standard uses a 32:4 DSSS chip-to-bit encoding.  
Because the CC2420 uses soft chip decision, there's no real concept  
of a "bit error." Instead, it effectively calculates the closeness of  
each chip to 0 and 1 and then chooses the symbol sequence which is  
closest to the soft chip decisions.

Phil