[Smac-users] the problem of unicast????

[ranosk]

hello,
   I am a number of a wireless sensor network team in china.   when use your smac code, I often find can't receive rtscts,data,ack.In order to eliminate the influence of channeland the hidden terminals,I wired two motes,one transmit,theother receive, still find a seriously lose of packets,especially ack.   Our boards and platform is done by ourselves. when tramsmitbrocadcast message,the lose of packet is 0.Why unicast packetoccur seriously lose?
   I think may be our PHY layer's transmit-receive time andreceive-transmit time is too long,so I prolong the SIFS to 2s,the lose of ack is lighten ,but still achieve 2%.  By use the UART debug message,we find when we transferthe PHY to transmit packet,the return value is often FAIL.   Do the problem occur in PHY layer?why bcastcast is good,but unicast is bad?I have stagnated 50 days,I don't knowwhat I can do next to solve this question. 
   I would deeply appreciate if someone can provide some clue on what might be going wrong.
   Thanks in advance for your time.
   Regards,
   ranosk  
   
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