I am using a MB6 and 007 and a large panel reader at a cattle alleyway.
The scenario I have in mind is two animals (with RFID), side by side running in lock step past a single panel
reader.Here the closer animal [A] hides...(by the mechanism of FM-Capture-Effect) his companion [B] and the
reader only reports the existance of the closer animal [A]... this is not good for commerce.
I conceived a technique that reads the distant tag first then the closer tag second, that is, a crude form of
collision avoidance based on spatial separation, (or field intensity).
I wish to modify TXCT such that every alternate power burst is gated "off" for 5mS after the first 15mS, and
then allowed to resume for the next 50mS. This reads tag [B]
The following or next power burst is to be classically 50mS duration. This cycle will keep repeating. This
reads tag [A].
By this "two-step-procedure" I anticipate that the "very close tag [A]" will be sufficiently charged in the
first 15mS then classically activated at the "End of Burst" time 15ms...however just as its telegram
begins,the charge field starts again (TXCT) and the reader-receiver ceases listening to it ...[A] telegram is
ignored.
However, while this is happening the more distant tag [B] which over the first 15mS never reached sufficient
charge to "arm" itself and therefore did not recognize the premature EOB at time 15mS, is simply lingering and
will resume charging from time 20mS...simultaneously the [A] tag is aimlesly discharging itself into the
either.
50 more milliseconds pass,during which [A] finishes its telegram and now [B] continues to aquire sufficient
charge and now is ready to sense the "second EOB" at 70mS (15+5+50)... now the [B] telegram is successfully
detected ...
Even though the obstructing [A] exists in "physical space" it no longer exists in "time space" ... a data
collision is avoided.
The next charge duration , (starting at time 90mS) is now classically 50mS long, after which the [A] tag (and perhaps [B]) reply, however only [A] is read and validated... regardless of whether [B] is there or not.
A "possible" crude form of spatial collision avoidance based on "near and far" at the expense of lost time, is proposed.
So...can I access the firmware inside the microcontroller on the MB2/6 boards to try this out?
I am not real good at programming, perhaps some forum member could offer help.
A variant on this is to enact a low power followed by a high power charge pulse, but this is for later. To
this end I see that the 007 use a RI45538NS which has a power control (pin13) which substantially reduces the
emitted charge field power...can any one speak to me about this (pin13)?
Does TI offer a customization service where they could change the firmware for me?...or is there some way to
use the utility S2 to make MB2/6 behave as I want?
My endeavour relates to collision avoidance or perhaps better described as mitigation.
Lastly, is there any chance TI would supply me a schematic circuit of the RFM-007or do I have to trace it out
myself given enough energy and time ...it would be real usefull.
Regards
Ray
