Hey all, I am using Wi-Spy to test a Zigbee application and I am noticing something strange. Wi-Spy is reporting its energy scan from a minimum of -61dB to -35idB for Channels 11-26. The values that the zigbee radio is reporting range from -96dB to about -56dB.
Is there something different about the ways that these values are scaled or is the wi-spy reporting more ambient noise? Or would I get better results if I compared the Zigbee energy scan to the Wi-spy spectograph?
Does anyone have any ideas?
Is your Zigbee radio reporting the energy of the Zigbee signal or the total energy in the band? One explanation would be that the wi-spy is reporting all the energy in the band.
Another reason for the discrepancy could be that the -61dBm signal that you are seeing is actually a lot lower (about 10 dB lower) in value. Note that the noise floor of the Wi-Spy is -60dBm, so it can't measure anything lower than that.
Submitted by Electric Monk on Wed, 08/02/2006 - 15:51.
Hey all, I am using Wi-Spy to test a Zigbee application and I am noticing something strange. Wi-Spy is reporting its energy scan from a minimum of -61dB to -35idB for Channels 11-26. The values that the zigbee radio is reporting range from -96dB to about -56dB.
Is there something different about the ways that these values are scaled or is the wi-spy reporting more ambient noise? Or would I get better results if I compared the Zigbee energy scan to the Wi-spy
spectograph? Does anyone have any ideas?
Ok. Thanks for your help
Electric Monk wrote:
Is your Zigbee radio reporting the energy of the Zigbee signal or the total energy in the band? One explanation would be that the wi-spy is reporting all the energy in the band.
Another reason for the discrepancy could be that the -61dBm signal that you are seeing is actually a lot lower (about 10 dB lower) in value. Note that the noise floor of the Wi-Spy is -60dBm, so it can't measure anything lower than that.
Hope that helps.
Hey all, I am using Wi-Spy to test a Zigbee application and I am noticing something strange. Wi-Spy is reporting its energy scan from a minimum of -61dB to -35idB for Channels 11-26. The values that the zigbee radio is reporting range from -96dB to about -56dB.
Is there something different about the ways that these values are scaled or is the wi-spy reporting more ambient noise? Or would I get better results if I compared the Zigbee energy scan to the Wi-spy
spectograph? Does anyone have any ideas?
:D Thanks V much! I have bought one & will get on with it.
Actually, the Zigbee frequencies currently shipping are 2.4Ghz ISM band. Wi-Spy is perfect for Zigbee 2.4Ghz testing.
David Peterson
Defacto Wireless Distribution LLC