Rong, How did you measure these numbers? There are a number of things that will affect the measurements:
- input voltage and boost converter. Boost converter essentially eliminates the ability to operate in sub-100 uA regime; for the measurements in the WSNA paper we did turn it off (we added a diode bypass). Likewise, different input voltages will operate at different efficiencies of the converter. Conversely, if you are bypassing the boost converter altogether (the mote will operate from 2.7 to 3.3V) will change the numbers quite a bit. - software -- in some versions of TinyOS, there was an IO pin conflict that resulted in motes drawing excess power. It has been fixed a number of times, but unfortunately it keeps reappearing. In general, the configuration of IO pins will have a large impact on the power consumption. - HW configuration -- I doubt that this would have affected you, but it is possible. Mica with Atmega128 can be configured to run with an internal RC oscillator at frequencies up to 8MHz. At these frequencies, the idle and active power consumed by the processor would be significantly larger than those published in WSNA. Let me know if I can be of further assistance. I would be curious to see what caused these discrepancies. Rob -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Rong Zheng Sent: Wednesday, October 01, 2003 9:08 AM To: [EMAIL PROTECTED] Subject: [Tinyos-users] Discrepancy in power consumption numbers hi, I recently did some measurements of the power consumption of Mica 128 motes. Here are the numbers I got, (all the numbers the power consumption of the entire system in particular state listed below) lower power (snooze) 0.97mA idle (with radio disabled) 4.97mA idle (with radio enabled) 11.30mA Tx (send raw RF through SpiByte) 12.90mA Rx 7.78mA The numbers are different from the ones I found from the ones given in WSNA'02 paper. In particular to receive an AM packet consumes roughly as much energy as transmitting an AM packet (see the attached eps files). I wonder if there is anything wrong with my measurement methodology. In my experiments, I removed all unnessary components. Thanks! Rong _______________________________________________ Tinyos-users mailing list [EMAIL PROTECTED] http://mail.Millennium.Berkeley.EDU/mailman/listinfo/tinyos-users _______________________________________________ Tinyos-users mailing list [EMAIL PROTECTED] http://mail.Millennium.Berkeley.EDU/mailman/listinfo/tinyos-users
