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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
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)
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
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.
-----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)
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!
-----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)
I'm
afraid I have to disagree and this is actually an example of the
point I have tried
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
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.
-----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)
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.
-----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
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