Re: [802.19] Question about path loss model

["Shellhammer, Steve" <sshellha@xxxxxxxxxxxx>]

Paul,

 

            Thanks for the clarification.  I figured that was one possibility.  My only concern with this model is it assumes free space propagation to 500m.  I would think that is optimistic and would expect the first breakpoint to be closer in.

 

            We can discuss this and other path loss models on the call.

 

Regards,

Steve

 

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From: Paul Piggin [mailto:ppiggin@nextwave.com]
Sent: Tuesday, April 10, 2007 9:08 AM
To: Shellhammer, Steve
Cc: stds-802-19@ieee.org; Adrian.P.Stephens@intel.com; bji@sta.samsung.com; bkraemer@ieee.org; dlubar@ieee.org; david.grandblaise@motorola.com; dickroy@alum.mit.edu; dougchan@cisco.com; eldad.perahia@intel.com; fm@octoscope.com; john.sydor@crc.ca; Kenneth Stanwood; marianna.goldhammer@alvarion.com; naftali.chayat@alvarion.com; shlomo.malka@alvarion.com; wuxuyong@huawei.com; amir.ghasemi@crc.ca
Subject: RE: Question about path loss model

 

Hi Steve,

 

Perhaps my notation was a little unclear. The interpretation I was applying was aligned with your first interpretation. So in summary:

 

1m to 500m: n=2

501m to 1000m: n=2.5

1001m to 4000m: n=3.5

4001m and greater: n=4

 

I will add this clarification, and the model itself, to the propagation model section of the simulation parameters document I’m currently working on.

 

I recall a comment, I think from Amir Ghasemi, suggesting the use the SUI large-scale fading model. This will take factors such as base station and subscriber station antenna heights into account. I’m sure this SUI model can be added to the simulation parameters document as it matures, or at least a definition of what assumptions should apply to configure the model.

 

Hope this helps.

 

Thanks,

Paul.

 

NextWave Broadband

 

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From: Shellhammer, Steve [mailto:sshellha@qualcomm.com]
Sent: Monday, April 09, 2007 6:37 PM
To: Paul Piggin
Cc: stds-802-19@ieee.org; Adrian.P.Stephens@intel.com; bji@sta.samsung.com; bkraemer@ieee.org; dlubar@ieee.org; david.grandblaise@motorola.com; dickroy@alum.mit.edu; dougchan@cisco.com; eldad.perahia@intel.com; fm@octoscope.com; john.sydor@crc.ca; Kenneth Stanwood; marianna.goldhammer@alvarion.com; naftali.chayat@alvarion.com; Shellhammer, Steve; shlomo.malka@alvarion.com; wuxuyong@huawei.com
Subject: Question about path loss model

 

Paul,

 

            I have a question about the path loss model you used in presentation 802.16h-07/38r1 on slide 11.

 

            The slide says the model is,

 

Propagation model

– d1=1m, d1=500m, d2=1000m, d3=4000m

– n1=2, n2=2.5, n3=3.5, n4=4

 

            I am a bit unclear on this.  There are four breakpoints and four exponents.  Typically, there are N breakpoints and N+1 exponents.  One interpretation is that the free space exponent of 2 is used between 1 and 500 meters.  Another interpretation is that free space is up to 1 meter and the exponent of 2.5 is used between 1 and 500 meters.

 

            Can you clarify your path loss model?

 

            I think it would be useful to have a common path loss model for everyone to use.

 

Thanks,

Steve