Google SAS CoEX value through API

[saurabh6000]

I've been working on retrieving the Coexistence (co-ex) values displayed on the SAS portal through the Spectrum Inquiry CBSD-SAS API. However, the API response I receive lists all available channels and their MaxEIRP values, but it does not seem to include the co-ex values as expected.

I watched a video (link: YouTube Video) where it was mentioned that the Spectrum Inquiry call should provide the co-ex values. However, I'm not seeing this information in the response.

Could someone please assist me in understanding if I am missing something or if there is a different approach to retrieve the co-ex values from the SAS portal? Your help would be greatly appreciated.

[James_S · Accepted solution]

Hi there!

The channel quality / Coex scores are unique to Google’s SAS Portal. They are not a part of SAS-CBSD communications and therefore cannot be pulled using the SAS-CBSD API.

However, the SAS does prioritize channel quality when it determines the order in which channels are suggested in the SI response. All things being equal, the SAS will provide the SI results in order of descending channel quality. Additionally, the Power today field for each channel in the SAS Portal’s ranking contains the same Max EIRP value that a SI result sent at the same time would provide. This is what was being discussed in the office hours video that you linked.

[saurabh6000]

So is there any way to access those values from APIs. If not could you please tell me if there is any particular reason not to expose this value or if there is any future plans to do this.

[James_S]

Spectrum Inquiry requests from CBSD to SAS on the CBSD-SAS interface provides maxEIRP for each channel. Google SAS ranks the channels according to a channel score which takes into account both interference conditions and allowed EIRP. This is strictly a machine to machine interface between CBSD and SAS.

SAS Portal is a UI interface, separate from the CBSD-SAS interface and presents information to the user and in some cases can augment information for users or network operators to analyze the deployment scenarios better. The Coex Tab in the portal provides Channel Score and EIRP for each 10 MHz channel.