[net2-wg] link estimator interface

[Philip Levis]

On Mon, 2006-03-06 at 13:35 -0800, Joe Polastre wrote:
> Again, correlation value is the state-full function, as per the specification.

I'm confused. Are you talking about this function:

  uint16_t correlation(uint8_t v) {
    uint16_t c = (80 - (v - 40));
    c = (((c * c) >> 3) * c) >> 3;
    return c;
  }

This is what all of the Moteiv code seems to use. It's stateless. 

It also does more than what ChipCon recommends in the CC2420 data sheet,
which is

LQI = (CORR - a) * b

which is also a stateless, linear function. Neither the ZigBee nor
802.15.4 specification seem to say anything about a stateful link
estimation function. Which specification are you thinking of?

Phil