Problem： Time interval are not equal. （under 20s update condition）

[Weigang Shogan Li]

Hi guys, 

Today I did an experiment by setting the update interval to 20 seconds. However I found out that the actual time step is not 20 second. 

Please refer to the clip below. 

Can anybody can explain to why it's not 20 second interval? What can we do to solve this so that the sensor tag can measurement exactly in 20 seconds step? 

Thanks. 

---Shogan

Student of Building Engineering. 

[Zhiheng Cao]

The transmission from each tag to tag manager is like emails or video streaming, if there is data loss due to weak signal the checksum will fail and the tag will have to retransmit. In your case the retransmission happens really often. What is the signal level?

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[Weigang Shogan Li]

Thanks. I do feel attribute to signal level will be a good shot to solve. 

 

Based on your message I moved the sensor tag to a place 30 cm away from the tag manager. This should guarantee the signal is strong enough. Also after the ping, the signal level is five bar full. 

However, under this condition, I tested 30 second interval, the update of temperature was still more or less than 30 s. Please refer to clip below:

Since I am planning to use the tag for mechanical experiment in my lab, I am quite looking forward to make sure the tag can update at constant interval. 

 

On Tuesday, July 21, 2015 at 7:45:10 PM UTC-4, mytaglist.com support wrote:

The transmission from each tag to tag manager is like emails or video streaming, if there is data loss due to weak signal the checksum will fail and the tag will have to retransmit. In your case the retransmission happens really often. What is the signal level?

On Tuesday, July 21, 2015, Weigang Shogan Li <weigang...@gmail.com> wrote:

Hi guys, 

Today I did an experiment by setting the update interval to 20 seconds. However I found out that the actual time step is not 20 second. 

Please refer to the clip below. 

Can anybody can explain to why it's not 20 second interval? What can we do to solve this so that the sensor tag can measurement exactly in 20 seconds step? 

Thanks. 

---Shogan

Student of Building Engineering. 

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