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



Title: Message
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 à 2305 - 2310 and 2350 - 2355 MHz

·         Channel Block B à 2310 - 2315 and 2355 - 2360 MHz

·         Channel Block C à 2315 - 2320 MHz

·         Channel Block D à 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

 

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]
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