 <p>From what I learned from the forums(<a href="https://www.millennium.berkeley.edu/pipermail/tinyos-help/2007-July/026348.html" rel="nofollow">https://www.millennium.berkeley.edu/pipermail/tinyos-help/2007-July/026348.html</a>) TOSSIM always sends at 0dbm and doesn't give dynamic change in the signal strength. Remember simulators have the limitations and Tossim assumes everything runs smoothly. But if you are interested in estimating quality you should consider some other parameter such as gain which can be programmed using the TOSSIM. </p>