Wi-Fi design for Voice - primary, secondary signal strength

[KlausD]

Hello,

I am having a few challenges to find the right answer for a proven VoWLAN design with regards to primary and secondary signal strength.

Some design guides are saying that both primary and secondary signal strength should be the same.

Ekahau best practise profile is having both primary and secondary set to -67dBm.
Other Ekahau profiles like Vocera are having -65dBm for primary and -75dBm for secondary.

Questions:
- what is your experience when designing for Voice with regards to primary and particularly secondary signal strength?
- how is the voice client affected when secondary signal strength is the same as primary vs less?

Thank you,

Klaus

[KlausD]

Thank you, Jan and Daniel.

While it's always about the client and designing / tuning your WLAN to it, I have a mixture of clients - Spektralink, Samsung Galaxy XCover Pros. The Spektralink can have its profile configured.
And every client sees a different RSSI which isn't a standardized value, so I am checking the RSSI in a couple of spots from both the client and the SideKick to determine the offset. 
Would you design with this defvice offset - around -10dBm which takes primary signal strength to -57 and secondary to -67?

Thank you,
Klaus

[Jan_Reister]

Hi Klaus, 2nd signal strength is about populating the AP roaming table and facilitating transition from one AP to the other. It is only one of the parameters like .11h neighbor report etc.

If you are designing VoWLAN for dedicated devices like Vocera, their guidelines are the source you want to check, because this vendors control the hw and chipset, tuning the exact thresholds that trigger a roaming event.

If you design for a voice app on a mass-market mobile device, check out the roaming documentation for iOS, Samsung Knox, Android stock. Each vendor documents the RSSI, SNR thresholds, roaming history that concur to the roaming decision. From there you can design the 2ndSS for your project.

[daniel598lopez]

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@KlausD wrote:

Hello,

I am having a few challenges to find the right answer for a proven VoWLAN design with regards to primary and secondary signal strength.

Some design guides are saying that both primary and secondary signal strength should be the same.

Ekahau best practise profile is having both primary and secondary set to -67dBm.
Other Ekahau profiles like Vocera are having -65dBm for primary and -75dBm for secondary.

Questions:
- what is your experience when designing for Voice with regards to primary and particularly secondary signal strength?
- how is the voice client affected when secondary signal strength is the same as primary vs less?

Thank you,

Klaus

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Hello @KlausD,
When designing for VoWLAN, it's crucial to balance primary and secondary signal strengths. Typically, both should be around -67 dBm for optimal performance. A stronger secondary signal ensures seamless roaming and redundancy, while a weaker secondary signal might cause disconnections or poor call quality.

Best regards,
Daniel Lopez