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Re: stds-80220-requirements: Spectral Efficiency (4.1.2)





Folks,

Let's get back on track.

There seems to be general consensus that guard bands should be taken
into account when calculating spectral efficiency. Joanne made 
a specific proposal for how to do this so let's get the discussion 
back to Joanne's suggestion:

From: "Joanne Wilson" <joanne@arraycomm.com>
To: "Shively, David" <david.shively@cingular.com>,
   <stds-80220-requirements@ieee.org>
Subject: RE: stds-80220-requirements: Spectral Efficiency (4.1.2)
Date: Mon, 24 Nov 2003 12:48:22 -0500

David,

Since we agree that a consistent approach for all technologies is the way to
go,  I think now we are just struggling a bit with the details of how to
achieve it.   To some extent, this discussion has become as much about the
evaluation process   (which is the purview of another CG) as it is about how
to define "network-wide bandwidth". In keeping with Bob Love's good advice
not to dive to deeply into the details at the requirements level, let's
trust (or encourage) the Evaluation CG to create a process that provides a
consistent approach to simulating the performance of the various proposals
within a fixed block size (possibly 5 MHz, which seems to be preferred by
many) and takes into consideration the need to confine the transmitted
signal energy, say at the 99% level, to within that fixed block.  To
calculate throughput in a specific scenario, the amount of spectrum that
must be allocated to guardbands to meet that 99% level would be subtracted
from the total available spectrum prior to multiplying by the calculated
spectral efficiency.  I believe the 99% number guarantees that the
variations in guardband requirements from one technology to the next won't
be all that significant. It appears to me that this level of detail should
be made  a proposal to the Evaluation CG and the definition of network-wide
bandwidth in the Requirements document could be left as is, or at least it
should be less detailed than the above.

Best regards,

Joanne

On Wed, Nov 26, 2003 at 11:56:00AM -0500, Shively, David wrote:
> Joseph,
>  
> I really have no idea what you are debating. 
>  
> What I had said was that an operator that has a licensed block of 5 MHz can
> only deploy
> 3 cdma2000 carriers (not 4).
>  
> If you assume that the operator has a license for a 15 MHz block, then it is
> possible to 
> deploy 11 carriers (not 12).
>  
> As Sprint had noted in the Albuquerque meeting, many frequency allocations
> around the world
> and in the US are based on a licensed block size of 5 MHz.  This includes
> the WCS spectrum that 
> you have mentioned.  Thus, if an operator has only a 5 MHz block, then a
> realistic deployment 
> scenario must include adequate guard bands within this block.
>  
> David Shively
>   
>  
>  -----Original Message-----
> From: Joseph Cleveland [mailto:JClevela@sta.samsung.com]
> Sent: Wednesday, November 26, 2003 10:38 AM
> To: 'Shively, David'; Anna Tee; 'stds-80220-requirements@ieee.org'
> Subject: RE: stds-80220-requirements: Spectral Efficiency (4.1.2)
> 
> 
> 
> Hi All, 
>  
> So I guess it appears that it is possible to put 4 CDMA carriers in 5 MHz of
> spectrum in a 15 MHz block or in a combined 15 MHz+5 MHz block.  Then, what
> are we debating?  
>  
> Has anyone examined the spectrum allocation for the WCS services?
> 
> *	WCS should be licensed initially as two 10 MHz channel blocks (with
> 5 MHz of this spectrum from the lower band paired with 5 MHz from the upper
> band) plus two 5 MHz blocks (those immediately adjacent to the satellite
> DARS spectrum). [page 23, FCC 97-05]  The specific channel blocks are as
> follows [page 24, FCC 97-05]:
> 
>          Channel Block A  2305 - 2310 and 2350 - 2355 MHz
> 
>          Channel Block B  2310 - 2315 and 2355 - 2360 MHz
> 
>          Channel Block C  2315 - 2320 MHz
> 
>          Channel Block D  2345 - 2350 MHz   
> 
> *	For out-of-band emissions, the requirement will be that all
> emissions from WCS fixed transmitters be attenuated below the transmitter
> power (p) by at least 80 + 10log(p) dB and that all emissions from WCS
> mobile transmitters be attenuated at least 110 + 10log(p) dB within the 2320
> - 2345 MHz band.  This level of attenuation is required in order to
> adequately protect satellite DARS reception from WCS transmissions.   [pages
> 70 - 71, FCC 97-05]
> 
> Note that guard bands are not specified but out-of-band emission
> requirements are specified.  The needed "guard band" now becomes an
> implementation issue.
>  
> Joseph Cleveland
> 
> -----Original Message-----
> From: owner-stds-80220-requirements@majordomo.ieee.org
> [mailto:owner-stds-80220-requirements@majordomo.ieee.org] On Behalf Of
> Shively, David
> Sent: Wednesday, November 26, 2003 8:46 AM
> To: 'Lai-King Tee'; stds-80220-requirements@ieee.org
> Subject: RE: stds-80220-requirements: Spectral Efficiency (4.1.2)
> 
> 
> Hi Anna,
>  
> Since 802.20 is intended to be deployed in licensed bands, the guard band
> requirements must be understood
> and accounted for in the design of the radio.  As I have said, if an
> operator has only a 5 MHz block, then it is 
> possible to deploy only 3 cdma2000 carriers (not 4).  If an operator has a
> 15 MHz licensed block, then it is possible
> to deploy only 11 carriers (not 12).  As you have noted, if an operator has
> licenses for two (or more) adjacent blocks
> (such as B and D), then it would be possible to deploy a total of only 15
> carriers in a total licensed block of 20 MHz
> ( 15 MHz B-block + 5 MHz D block = 20 MHz).   Under the Part 24 rules for
> PCS, guard bands are not required 
> between licensed blocks if both blocks are licensed to the same operator.
>  
> Best regards,
> David Shively
> 
> -----Original Message-----
> From: Lai-King Tee [mailto:a.tee@samsung.com]
> Sent: Tuesday, November 25, 2003 5:41 PM
> To: 'Shively, David'; stds-80220-requirements@ieee.org
> Subject: RE: stds-80220-requirements: Spectral Efficiency (4.1.2)
> 
> 
> 
> Hi David,
> 
>  
> 
> Thanks for the link to the 3GPP2 web site. In Table 2.1.1.1.2-3 of C.S2002-C
> v1.0, the CDMA channel numbers for Band Class 1 (PCS band in the US) and
> spreading rate 1 are listed. Using Block B (15 MHz) as an example, it is
> shown that the CDMA channel numbers between 425 and 675 are always valid,
> whereas the ones between 400 and 424, and those between 676 and 699 are
> marked conditionally valid. It is true that there are 11 channels that are
> always valid - also listed in Table 2.1.1.1.2-5 as "preferred" channel
> numbers. However, the standard didn't seem to exclude the option of
> deploying 12 channels within the block. Would it be possible to have a
> scenario in which an operator owns both adjacent blocks. e.g., Blocks D and
> B, so that the operator can decide to use channel number 400 in addition to
> the 11 preferred channels? In this scenario, it would be possible to deploy
> 12 CDMA channels in 15 MHz bandwidth. 
> 
>  
> 
> Best regards,
> 
> Anna.
> 
>  
> 
>  
> 
> -----Original Message-----
> From: owner-stds-80220-requirements@majordomo.ieee.org
> [mailto:owner-stds-80220-requirements@majordomo.ieee.org] On Behalf Of
> Shively, David
> Sent: Tuesday, November 25, 2003 12:13 PM
> To: stds-80220-requirements@ieee.org
> Subject: RE: stds-80220-requirements: Spectral Efficiency (4.1.2)
> 
>  
> 
> Hi Anna,
> 
>  
> 
> Thank you for providing this information.  You are correct that adjacent
> cdma2000 carriers may be 
> 
> placed adjacent to one another.   This is exactly what I had said in my
> previous email below.  
> 
>  
> 
> At the edge of a 5 MHz licensed frequency block, there is typically a guard
> band of 625 kHz.  As you
> 
> have noted, this is to avoid interference to an operator in an adjacent
> frequency block.  With a guard band
> 
> of 625 kHz on each end of a 5 MHz block, this leaves only 3.75 MHz of
> spectrum, e.g. this will allow
> 
> the deployment of 3 cdma2000 carriers where each carrier is 1.25 MHz.  
> 
>  
> 
> In the case of a 15 MHz licensed spectrum block, it is possible to deploy a
> total of 11 cdma2000 
> 
> carriers, not 12.
> 
>  
> 
> Additional details can be found in:  Physical Layer Standard for cdma2000
> Spread Spectrum Systems
> 
> available at http://www.3gpp2.org/Public_html/specs/index.cfm
> <http://www.3gpp2.org/Public_html/specs/index.cfm> 
> 
>  
> 
> Also, again as I had indicated in my previous email, if an operator had a
> licensed allocation of only
> 
> 1.25 MHz then there is no realistic way to deploy this type of system since
> the necessary guard bands 
> 
> would fall out of this block and onto the adjacent operators.     
> 
>  
> 
> Best regards,
> 
> David Shively
> 
>  
> 
>  
> 
>  -----Original Message-----
> From: Lai-King Tee [mailto:a.tee@samsung.com]
> Sent: Tuesday, November 25, 2003 2:03 PM
> To: 'Joseph Cleveland'; 'Shively, David'; stds-80220-requirements@ieee.org
> Subject: RE: stds-80220-requirements: Spectral Efficiency (4.1.2)
> 
> Hello David,
> 
>  
> 
> Based on what I found from the reference material*, the guard band is used
> in the CDMA (IS-95) system when the adjacent frequency channel may have high
> power signal transmissions. However, there is no need for guard bands
> between adjacent CDMA channels. 
> 
>  
> 
> The reason that the first CDMA 2000 channel is usually deployed further away
> from the edge of the licensed band is probably to avoid high interference
> power from the adjacent frequency channel that has been used for other high
> power wireless systems.
> 
>  
> 
> *Reference: "Jerry D. Gibson, The Mobile Communications Handbook, Chapter
> 27, IEEE press, 1996.
> 
>  
> 
> Best regards,
> 
> Anna.
> 
>  
> 
> -----Original Message-----
> From: owner-stds-80220-requirements@majordomo.ieee.org
> [mailto:owner-stds-80220-requirements@majordomo.ieee.org] On Behalf Of
> Joseph Cleveland
> Sent: Tuesday, November 25, 2003 8:53 AM
> To: 'Shively, David'; 'stds-80220-requirements@ieee.org'
> Subject: RE: stds-80220-requirements: Spectral Efficiency (4.1.2)
> 
>  
> 
> David,
> 
>  
> 
> I disagree with your analysis.  For example, PCS D/E/F-Block (5 MHz)
> operators currently use carriers separated by 1.25 MHz with all channels
> assigned.  If an operator has a 15 MHz block (e.g., A/B/C-Block), the
> operator can use the entire spectrum with carriers placed 1.25 MHz apart
> across the entire block - for a total of 12 carriers, not 9. It is realistic
> to deploy a system with a chip rate of 1.2288 Mcps in a 1.25 MHz bandwidth!
> 
> 
>  
> 
>  Joseph Cleveland
> 
>  
> 
> -----Original Message-----
> From: owner-stds-80220-requirements@majordomo.ieee.org
> [mailto:owner-stds-80220-requirements@majordomo.ieee.org] On Behalf Of
> Shively, David
> Sent: Tuesday, November 25, 2003 10:00 AM
> To: 'stds-80220-requirements@ieee.org'
> Subject: RE: stds-80220-requirements: Spectral Efficiency (4.1.2)
> 
> Joseph,
> 
>  
> 
> I'm afraid I have to disagree and this is actually an example of the point I
> have tried
> 
> to clarify.
> 
>  
> 
> In some cases, yes, cdma2000 carriers can be placed directly adjacent to one
> another,
> 
> although there is some degradation in overall capacity when this is done.
> However, in 
> 
> most deployments the first cdma2000 channel that is used is 1.25 MHz away
> from the 
> 
> edge of the licensed band.  This means that there is a guard band of approx.
> 625 kHz 
> 
> between the first cdma2000 carrier and the edge of a licensees spectrum
> allocation.
> 
> This is why an operator can use 3 cdma2000 carriers in a 5 MHz block of
> licensed spectrum
> 
> rather than 4.  
> 
>  
> 
> If an operator had a license for only a 1.25 MHz block of spectrum, then I
> do not think it would 
> 
> realistic to deploy a system with a chip rate of 1.2288 Mcps.
> 
>  
> 
> David Shively
> 
> -----Original Message-----
> From: Joseph Cleveland [mailto:JClevela@sta.samsung.com]
> Sent: Tuesday, November 25, 2003 9:51 AM
> To: 'Shively, David'; 'stds-80220-requirements@ieee.org'
> Subject: RE: stds-80220-requirements: Spectral Efficiency (4.1.2)
> 
> David,
> 
>  
> 
> I believe that if you look at the spectrum allocation scheme and spectrum
> emission mask for CDMA2000 you will find that 1.25 MHz does include the
> guard bands.  The CDMA2000 channel spacing is 1.25 MHz.
> 
>  
> 
> Joseph Cleveland
> 
> -----Original Message-----
> From: owner-stds-80220-requirements@majordomo.ieee.org
> [mailto:owner-stds-80220-requirements@majordomo.ieee.org] On Behalf Of
> Shively, David
> Sent: Monday, November 17, 2003 3:06 PM
> To: stds-80220-requirements@ieee.org
> Subject: RE: stds-80220-requirements: Spectral Efficiency (4.1.2)
> 
>  
> 
> Regarding these definitions, it should be clearly understood whether 
> or not guard bands are accounted for in the calculation of spectral 
> efficiency.  For UMTS (W-CDMA), the channel is usually quoted as being 
> 5 MHz wide.  In this case the guard bands have been included.  However, 
> for cdma2000 1X (and IS-95) the channel is usually quoted as being 
> 1.25 MHz wide which does not include the necessary guard bands. 
> 
> I propose the following: 
> 
> Network Wide Bandwidth:  The network wide bandwidth is the total spectrum in
> 
> use by the unique carriers deployed in the network, including any 
> required guard bands. 
> 
>  
> 
> Best regards, 
> David Shively 
> ----------------------------------------------------------- 
> Dr. David Shively 
> Cingular Wireless 
> 5565 Glenridge Connector, Mail Stop 950 
> Atlanta, GA 30342 
> Phone:  404 236 5909 
> Mobile: 404 285 5731 
> FAX:    404 236 5949 
> email:  david.shively@cingular.com 
> pager:  dshively@imcingular.com 
> 
> 
> 
> 
> 
> -----Original Message----- 
> From: Humbert, John J [NTWK SVCS] [ mailto:JHumbe01@sprintspectrum.com
> <mailto:JHumbe01@sprintspectrum.com> ] 
> Sent: Monday, November 17, 2003 12:08 PM 
> To: stds-80220-requirements@ieee.org 
> Cc: mike@arraycomm.com 
> Subject: stds-80220-requirements: Spectral Efficiency (4.1.2) 
> 
>  
> 
> Below is the latest version of the text that was developed at the Plenary in
> Albuquerque along with a list of the open issues for this section. 
> 
> *       4.1.2   System Spectral Efficiency (b/s/Hz/sector) 
> *       The system spectral efficiency of the 802.20 air interface shall be
> quoted for the case of a three sector baseline configuration [Footnote 1].
> It shall be computed in a loaded multi-cellular network setting, which shall
> be simulated based on the methodology established by the 802.20 evaluation
> criteria group. It shall consider among other factors a minimum expected
> data rate/user and/or other fairness criteria, and percentage of throughput
> due to duplicated information flow. The values shall be quoted on a
> b/s/Hz/sector basis. The system spectral efficiency of the 802.20 air
> interface shall be greater than X b/s/Hz/sector. 
> 
> *       Footnote 1: Since the base configuration is only required for the
> purpose of comparing system spectral efficiency, proposals may submit
> deployment models over and beyond the base configuration.
> 
>  
> 
> *       Definition: 
> *       System spectral efficiency - System spectral efficiency is defined
> as the ratio of the aggregate throughput (bits/sec) to all users in the
> system divided by the network wide bandwidth (Hz) and divided by the number
> of sectors in the system. 
> 
> *       Aggregate Throughput: Aggregate throughput is defined as the total
> throughput to all users in the system (user payload only). 
> 
> *       Network Wide Bandwidth:The network wide bandwidth is the total
> spectrum in use by the unique carriers deployed in the network.
> 
>  
> 
> *       Open items 
> -       Single value vs. multiple for uplink and downlink 
> -       X bits/sec/Hz [note 1 b/s/Hz -or- downlink > 2 b/s/Hz/(cell or
> sector?) @ 3km/hr ;uplink > 1 b/s/Hz/(cell or sector?) @ 3 km/hr].
> 
> -       Actual values of spectral efficiency at higher speeds 
> -       TDD/FDD 
> 
>  
> 
> John J. Humbert 
> 6220 Sprint Parkway 
> Mailstop KSOPHD0504 - 5D276 
> Overland Park, KS 66251-6118 
> PCS (816) 210-9611 
>