Transcript Nett incidence of License Fee, Spectrum Charges & Service Tax

Spectrum & 3G services
AUSPI Presentation to TRAI
01.08.06
UASL LICENSE & 3G
PRIME ISSUES
INTERFERENCE ISSUES
SUGGESTIONS
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UASL LICENSE & 3G
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3G Policy !
• UASL License permits provision of voice and data services and
does not distinguish between 2G & 3G.
• Flexibility to provide any service permitted under the license.
• 3G is not a new service – no new policy required
• 3G in its simplistic form is nothing but enhanced data
application along with multimedia - not a new service. Such
services already exist (eg,: EDGE in GSM)
• Since TRAI considering the issue afresh- consider bringing
level playing field between operators using different
technologies; CDMA & GSM
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3G Policy !
• No reservation of spectrum for BSNL/MTNL
• Present technology neutrality only to the extent that
DOT does not enforce any technology.
• Establish technology neutrality in real sense and
allocate spectrum– let operators use any technology
to provide any service permitted under the licence.
• TRAI/DOT should make efforts to get the spectrum in
India used for telecom services universally.
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PRIME ISSUES
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Prime Issues
•
What is 3G?
• Band Allocation
– 2100 MHz for both CDMA & GSM operators
– Appropriateness of 2100 MHz for CDMA operators
• Is 2100 MHz the only band for 3G?
– Many options to TRAI for consideration for 3G Services
• Mixed band allocations and interference issues
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3G – What is it?
• According to ITU, some key requirements of 3G
service include
–
–
–
–
Improved system capacity
Backward compatibility with 2G systems
Multi media support and
High speed packet data services meeting the following
criteria
•
•
•
•
2 mbps in fixed or in building environments
384 kbps in pedestrian or urban environments
144 kbps in wide area mobile environments
Variable data base in large geographic area systems (satellite)
Present UASL licence permits all these features/ capabilities
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3G – What is ITU saying?
3G is a term coined by global cellular community to indicate the
next generation of mobile service capabilities (Higher capacity /
Enhanced network Functionalities) that allow advanced
services and applications, including multimedia – ITU
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3G & ITU
Some Key observations
• ITU Defines the capability of 3G and not the association of the
same with any particular frequency band
• Ensuring economies of scale by use of global standards and
meeting needs of mass market and international roaming
• As per ITU definitions and global best practices, 3G is a service
that is agnostic to frequency band of use.
• CDMA2000 and WCDMA both qualify for 3G services and more
importantly in any frequency band that they operate in.
• USA is an example for demonstration of operational 3G
systems in non-2100MHz band
In the US, 3G services including WCDMA operate in
non-2100 MHz bands; they operate in 850/900/1900 MHz band!!!
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Is 3G band specific?
• NO
• Equating 3G or for that matter WCDMA with 2100 is not appropriate
• As defined by ITU and already practiced by some of the countries, 3G
is completely band-agnostic
• In the US 3G services including WCDMA operate in 850/1900 MHz
band.
• Similarly, incumbent GSM operators in the world in 900 & 1800MHz are
working out deployment options in 900 & 1800MHz! (Telstra is an
example)
• Yet another example of WCDMA becoming applicable in 1800MHz is
proven by already available commercial equipment availability –
Huawei’s announced equipment availability in 1800MHz!
AUSPI would urge TRAI to take cognizance of these developments
while arriving at spectrum decisions for WCDMA/3G allocations and
NOT limit itself to analysis of 2100MHz
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Band Allocation…Inappropriateness of 2100
MHz for CDMA
• Key criteria needed in selecting frequency band for
any cellular operation
• Network equipment availability
• Handset availability [Consider dual band with existing freq
(800MHz)]
• Global Roaming support
• Economies of scale
• Time to market
• Choice of vendors and wide range in models
Does 2100 MHz for CDMA meet any of these criteria?
The answer is NO
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Band Allocation…Inappropriateness of
2100MHz for CDMA
• No vendor is making compatible equipment in 800 and 2100
MHz bands.
• Dual band handsets in 800 and 2100 MHz combination neither
AVAILABLE nor do they figure in the manufacturing program
of vendors.
• All International CDMA networks are in 800 and 1900 MHz.
Global roaming support will be possible in these bands only.
• 2100MHz for CDMA fails on the account of lack of global
economies of scale, choice in vendor selection.
• Allocation of 2100MHz for CDMA will put the operators at a
disadvantage compared to GSM operators in terms of
appropriate time to market and parity with competition.
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Mixed band
• Mixed band allocation between IMT bands B3 & B1
As per ITU Recommendation M.1036-2
– IMT-2000 systems can be deployed in any band- multiple
bands have been identified for IMT-2000 systems
– Permit flexibility to administrations to deploy IMT-2000
systems even in bands other than those identified in the RR.
• Solution for India
– Mixed band is the only practical solution in India which
ensures growth and evolution of both CDMA and GSM
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Issues in Mixed band
• Does it lead to interference
-
Yes
• Is there a solution
-
Yes
• Is the solution technically feasible?
-
Yes
• Is it economically viable?
-
Yes
So what is the analysis and recommendations?
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INTERFERENCE ISSUES
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Outline
Background and Requirement
Study on how to mitigate the effect of C2K Base
Station Transmit on WCDMA Node-B Receive
Study on how to mitigate the effect of WCDMA
Handset (UE) Transmit on C2K Handset Receive
Field Trial in India to demonstrate co-existence
of WCDMA and CDMA in 1900MHz band
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ITU defined Band allocations near 2 GHz
• ITU band 1, commonly termed the “UMTS” band
– UL:1920- 1980/ DL:2110 -2170 MHz
• ITU band 3, commonly termed the “PCS” band
– UL:1850-1910/ DL:1930 - 1990 MHz
US PCS 1900 MHz Band
1850
1910
1930
1990 MHz
Base station TX
Mobile TX
Mobile TX
1920
1850
1900
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Spectrum
Overlapping Zone
IMT2000 2100 MHz Band
1980
1950
Base station TX
2110
2000
2050
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2100
2170 MHz
2150
2200
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Possible Spectrum Allocation Plan around 2 GHz
(Mixed Band Plan)
• ITU band 1, commonly termed the “UMTS” band
– UL:1920- 1980/ DL:2110 -2170 MHz (60+60 MHz)
• ITU band 3, commonly termed the “PCS” band
– UL:1900-1910/ DL:1980 - 1990 MHz (10+10 MHz)
US PCS 1900 MHz Band
1900 1910
1980 1990 MHz
Base Station TX
Mobile TX
Mobile TX
1920
1850
1900
IMT2000 2100 MHz Band
1980
1950
Base Station TX
2110
2000
2050
2100
2170 MHz
2150
2200
1980 MHz Boundary
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Interference Issues in Mixed Band Plan
(at 1980 MHz Boundary)
• Major interference issues are:
– PCS band (C2K) Base Station Transmit affecting UMTS
band (WCDMA) Base Station (Node B) Receive
– UMTS band (WCDMA) Mobile (UE) Transmit affecting the PCS
band (C2K) Mobile (MS) Receive
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Case 1:
Study on how to mitigate the effect of C2K Base Station
Transmit on WCDMA Node-B Receive
Definition:
1. Isolation is the loss between the antenna sockets of the aggressor Tx and
the victim Rx
2. C-C spacing is different from GB, but is related in the following way:
C-C spacing = (A/2+B/2)+GB where A and B are assigned channel
bandwidths of adjacent carriers
3. Channel bandwidth is higher than occupied bandwidth based on the slope
of the stop band skirt
4. Guard band is therefore the edge to edge frequency separation
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CDMA BTS to UMTS BTS Interference
Analysis Model
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CDMA BTS to UMTS BTS Interference
Analysis Principle
• Principle I:
The received out-of-band emissions at WCDMA Node B from the
CDMA BTS transmitter should be 10dB below the WCDMA Node B
receiver noise floor.
• Principle II:
Carrier TX power of CDMA BTS should satisfy WCDMA ACS
(Adjacent Channel Selectivity) requirements.
• 3rd order IMP is not a major interference source, specially under
enough C-C spacing separation.
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C2K BTS Tx Power Amplifier Out put in PCS band
PA out RF spectrum chart of a
C2K Carrier @ 1981.25 MHz
When PA output power is
45.4dBm[=29.40dBm+10×log1
0(1.250MHz/30kHz)],
Mark1—central of 1X carrier
Mark2—offset of 3.125MHz
Mark3– offset of 4. 375MHz
Mark4-- offset of 5.625MHz
Spurious emission is
-31.85dBm/30kHz, (Mark2)
-38.42dBm/30kHz, (Mark3)
-43.15dBm/30kHz (Mark4)
individually.
Duplexer Filter would provide further reduction to this OOBE Spurious emissions
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C2K BTS Tx Duplexer Out put in PCS band
Characteristics of a
Duplexer/Filter in C2K BTS
for 1980 to 1990 MHz range
For edge to edge Guard
Band of 2.5MHz
[=1983.12(Marker 3)1980.625(Marker 5)],
=-1.7010-(-32.783)
=31.082dB attenuation
can be achieved by
build-in filter in RFE
Duplexer. And with
additional filter extra
attenuation of 30dB Is
possible.
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Out-of-band emission limits
in 3gpp2/ITU Spec for 1.9GHz CDMA Transmitter
Table 4.4.1.3-2. Band Class 1, 4, 6, and 8 Transmitter Spurious Emission
Limits of C.S0010-C_v1.0
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Isolation requirement for
Out-Of-Band (OOB) Emissions
•
UMTS band of 3.84 MHz Noise Floor = K*T*B+NoiseFigure
=10× log10(1.38×10-23×290×3.84×106)+4
= -134.2dBW
= -104.2dBm(/3.84MHz)
•
Acceptable interference is at least 10 dB below receiver noise floor in the band
of concern (3.84 MHz)
– - 104.2 – 10 = - 114.2 dBm/3.84 MHz
•
As per the Out-of-band emission (OOBE) limit by 3GPP2 for PCS, CDMA BTS
transmit OOBE should not exceed - 13 dBm/MHz(-28.23 dBm /30KHz) beyond
1.625 MHz frequency offset from block edge
– For the UMTS band of concern it is - 13 + 10 log (3.84) = -7.2 dBm/3.84 MHz
•
Hence, the worst case calculation for the OOBE isolation requirement from ITU
B3 CDMA to ITU B1 WCDMA should be
– - 7.2 - (- 114.2) = 107 dB (Worst Case)
– This isolation requirement =
CDMA BTS Duplexer filter + Additional TX filter + Antenna space isolation
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WCDMA Node B Adjacent Channel
Selectivity requirement
Wanted signal mean
power >-115dBm
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Interfering signal mean
power < -52dBm
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Isolation requirement for WCDMA
Node B Rx Blocking
• WCDMA Node-B Receiver can tolerate the adjacent channel (out-ofband) signal level of around - 52 dBm and below.
• The maximum level of the CDMA BTS transmit signal in WCDMA
adjacent channel is 47.8 dBm (combined signal of 3 20W CDMA
carriers)
– 43dBm[20Watt]+10lg(3)=47.8dBm
• Hence, the worst case calculation for isolation requirement for receiver
blocking will be
– 47.8 - (- 52) = 99.8 dB = ~ 100dB
– From this result, it is observed that the Isolation requirement for
Receiver blocking (100 dB) is less than the isolation requirement
for the Out-of-band emissions (107 dB)
– Therefore, if we obtain the required isolation for OOBE that would
be sufficient against receiver blocking for interfering signals at +/- 5
MHz and beyond
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Techniques to achieve the required Isolation
• Techniques to achieve the required Isolation in order
to combat the Interference effects (both OOBE and
Blocking)
– Separation between WCDMA and C2K carriers
– Extra Bandpass filtering in the C2K Base Station transmit path
– Extra Bandpass filtering in the WCDMA Node-B receive path
– Antenna Isolation (between WCDMA and C2K base station antennas)
through physical separation and proper antenna orientation
C-C spacing
Separation
Guard Band
C2K Base Station transmit
filtering
WCDMA Node-B
receive filtering
Big (>6.35MHz)
3.8 MHz
Low Cost
Low cost
Small (3.85MHz)
1.3 MHz
High cost
High cost
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Examples of C-C spacing between the Last WCDMA
and the first C2K carrier
a)
With 3.85 MHz C-C Separation
GB=3.85-0.625-1.925=1.3MHz
2.6 MHz
b) With 5 MHz C-C separation
GB=5-0.625-1.925=2.45MHz
2.6 MHz
1.25 MHz
First
C2K
Carrier
Last
WCDMA
Carrier
First
C2K
Carrier
Last
WCDMA
Carrier
5 MHz
3.85 MHz
1977.4 MHz
1981.25 MHz
1977.4 MHz
1982.4 MHz
1980 MHz boundary
1980 MHz boundary
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How much C-C Sep/Guard Band is really required?
•
Required C-C separation can be decreased based on bandpass
filtering
– With minimum C-C separation of 3.85 MHz, there is some inherent guard
band(1.3MHz) available between the last WCDMA and the first C2K carrier
– Cost of C2K special BTS TX filters would depend on the roll-off
characteristics
– Steeper roll-off requirement would increase cost of the special filters
– Reasonable cost bandpass filters are available in the market that would
provide 60 dB attenuation (from pass band to stop band) within 1.3 MHz from
the edge of the pass band (See next slide for characteristics of such filter)
• As per the Out-of-band emission (OOBE) limit stipulated by 3GPP2 for
the PCS band operations, C2K BTS transmit OOBE would be less than 13 dBm/MHz beyond 1 MHz of frequency offset
• Any extra guard band beyond 1 MHz would ease design cost on the
special filters in C2K BTS Tx path for OOBE interference reduction
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Suitable C2K BTS Tx Bandpass Filter Characteristics
(with passband from 1980 to 1990 MHz)
~1.3 Mhz
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C-C spacing Recommendations
• Alternative 1: With additional C2K BTS Tx Filter (that would provide
60 dB stop band attenuation) as well as WCDMA Node-B receive Filter
(with 40+ dB stop band rejection):
– Recommended C-C spacing is 3.85 MHz(GB=1.3MHz)
– Here, we get 7 C2K carriers in full 10+10 MHz of PCS band
• Alternative 2: With only C2K BTS Tx Filter and no WCDMA Node-B Rx
Filter
– Recommended C-C spacing is 5 MHz (GB=2.45MHz)
• One way to get is by shifting C2K carriers away from 1980 MHz boundary
– In this case, we get only 6 C2K carriers in PCS band
• Alternative 3: With no additional filters in both C2K BTS transmit and
WCDMA Node-B receive paths
– Recommended C-C spacing is 6.35 MHz (GB=3.8MHz)(with duplexer in
C2K BTS Tx)
– Any more separation beyond 6.35 MHz is not going to be effective
– With this allocation plan, we get only 5 C2K carriers in PCS band
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C-C spacing Recommendations Figures
Alternative 1: Additional filter attenuation in CDMA TX and WCDMA RX
Alternative 2: Additional filter attenuation only in CDMA TX path
Alternative 3: No additional filters in CDMA and WCDMA BTS
• WCDMA spectrum will not be effected by present of CDMA;
• In case of co-existence of WCDMA and CDMA operation in 1900MHz band, additional filtering attenuation of
40dB will be needed in the WCDMA RX path.
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Antenna deployment strategy
between C2K BTS and WCDMA Node B
• Alternative1: With filters on both C2K and WCDMA BTSs
– If sharing the same antenna tower and site
• Vertical separation of > 1 m would give 50 dB of suppression
– Different antennas on the same site (Near Field)
• Horizontal separation of >12 m would give 50 dBm of
suppression (Gtx+Grx=10dB )
• H-V separation based on the formula shown in the next slide
• Alternative 2: With C2K Tx filter but no WCDMA Rx filter
– It is the same as the first case
• Alternative 3: With no filters in both C2K and WCDMA BTSs
– Around 800 m to 1 km of site separation (is not practical)
• Possibility of certification from all the major Infrastructure vendors that
they can include this filtering in the C2K base stations is required
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Formulae to calculate the Antenna
Isolation availability
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Isolation Example
Horizontal Isolation
h-isolation Gtx+Grx=0(dB)
h-isolation Gtx+Grx=10(dB)
h-isolation Gtx+Grx=30(dB)
70.00
60.00
Vertical Isolation
v-isolation(dB)
50.00
110.00
40.00
100.00
30.00
90.00
20.00
80.00
70.00
10.00
60.00
0.00
1
2
3
4
5
6
7
8
9
10
11 12
meter
13
14
15
16
17
18
19
20
50.00
40.00
Gtx+Grx=30dB is nearly face
to face installation.
30.00
20.00
1
2
3
4
6
5
7
8
9
(meter)
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10
Free Space path loss model for the PCS band
Free Space Transmission Loss vs Distance (Assumes Isotropic Antennas)
1980 MHz
15.0 Meter BTS 15.0 Meter
-50
-60
-70
Loss (dB)
-80
-90
-100
-110
-120
-130
-140
0.01
0.10
1.00
Distance (Km)
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C2K BTS to WCDMA Node-B Interference: Summary
• Up to 107 dB of isolation is required to mitigate interference due to CDMA
BTS TX affecting WCDMA Node-B RX, for both OOB emission and blocking
• In normal practice, around ~50 dB of antenna isolation is quite easy to get
with good installation practices, for both co-located and non co-located
cases
• With filters in both C2K and WCDMA BTSs, a min C-C frequency of 3.85 MHz
(GB=1.3MHz) is required to take care of the interference issues
– Band pass filter with 60 dB out-of-band rejection/attenuation in CDMA BTS
transmit path is realizable with 3.85 MHz of C-C separation
– Cost of band pass filters would go down with 5 MHz of C-C separation
• With filters in only C2K BTS Tx path, a min C-C separation of 5 MHz
(GB=2.45MHz) is required to take of the effect of IM products
• With no filters in both C2K and WCDMA BTSs, a min C-C separation of 6.35
MHz (GB=3.8MHz) and a site to site separation of around 800 meters is
required
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Comparison Table for the 3 Alternatives
Working
C-C
Separatio
n >/=
Guard
Band
Antenna separation
requirement
Alternative 1: 3.85 MHz
Filters in
both BTSs
1.3MHz
Practical antenna separation:
for 50dB isolation >1m
Vertical sep or >12m
Horizontal sep for same site
Alternative 2: 5 MHz
Filter in C2K
BTS only
2.45MHz
Practical antenna separation:
for 50dB isolation >1m
Vertical sep or >12m
Horizontal sep for same site
Alternative 3: 6.35 MHz
No filters in
both BTSs
3.8MHz
Unrealistic antenna / site
separation
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Case 2:
Study on how to mitigate the effect of
WCDMA Handset (UE) Transmit on
C2K Handset Receive
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Some important observations with mobile behavior
• Handset distribution and usage is highly stochastic in nature
– WCDMA UE and C2K MS both must be active for
interference to occur
– If WCDMA UE spurious emissions are better than standards
specified values, then the interference effect would also be
less
• In general, the maximum Tx power of a class 3 WCDMA UE is
around 10 dBm (which is 11 dB below its assigned peak power
of 21 dBm)
• Finally, it leads to the conclusion that UE to MS interference is
expected to occur in a relatively small percentage of the time
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WCDMA UE Emission Mask
Minimum Spectrum mask Emission Requirement:
– For frequency offset from 2.5 MHz to 3.5 MHz, - 20 – 15(Δf – 2.5) dBc / 1 MHz
– For frequency offset from 3.5 MHz to 7.5 MHz, - 35 – 1(Δf – 3.5) dBc / 1 MHz
– For frequency offset from 7.5 MHz to 8.5 MHz, - 39 – 10(Δf – 7.5) dBc / 1 MHz
– For frequency offset from 8.5 MHz to 12.5 MHz, - 49 dBc / 1 MHz
0
Relative Carrier Level in dBc
•
- 10
- 20
- 30
3.85MHz offset, - 35.4 dBc/1 MHz
5MHz offset, - 36.5 dBc/1 MHz
- 40
- 50
- 10
-8
-6
-4
-2
0
2
4
6
8
10
Frequency Offset in MHz
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Isolation requirement for C2K Mobile RF Blocking
•
As per the OOBE specifications, at 3.85 MHz away from center frequency, WCDMA
OOBE would be - 35.4 dBc/1 MHz
– At 5 MHz frequency offset, WCDMA OOBE would be – 36.5 dBc/1 MHz
•
The peak power of WCDMA UE is 21 dBm (for a class 3 device) @ 3.84 MHz, i.e., 15
dBm/1 MHz
•
From the emission specifications we can derive:
– At 3.85 MHz frequency offset, WCDMA OOBE is -35.4 - (-15) = - 20.4 dBm/1 MHz
– At 5 MHz frequency offset, WCDMA OOBE is -36.5 - (-15) = - 21.5 dBm/1 MHz
•
C2K Handset Adjacent Channel Selectivity (ACS) is - 68 dBm/ 1 MHz
– Amount of isolation required to take care of the de-sensitization of C2K Mobile
from the WCDMA UE TX signal is - 20.4 - (- 68) = 47.6 dB
•
As per the 2 slope path loss model, we can get this 47.6 dB of path loss within less than
1 meter distance from the mobile transmitter antenna
– Hence, from RF blocking point of view, there is no interference problem from
WCDMA UE transmit signal to C2K MS receive
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Isolation requirement for C2K Mobile
Out-of-band Emissions
•
From the emission specifications, at 3.85 MHz frequency offset, WCDMA OOBE
comes to - 20.4 dBm/1 MHz
•
C2K Handset receive filter rejection specification for 3.85 MHz offset from its desired
signal would be around 37 dB
– WCDMA OOBE signal received by C2K mobile @ 3.85 MHz offset is (-20.4 - 37)
= - 57.4 dBm/1 MHz and @ 5 MHz offset it is - 58.5 dBm/1 MHz
•
Acceptable interference at C2K mobile is - 116 dBm/1 MHz (10 dB below receiver
noise floor of -106 dBm /1 MHz)
– Amount of isolation required to take care of the OOBE for C2K Mobile from the
WCDMA UE TX signal is - 57.4 - (-116) = 58.6 dB
– Amount of isolation required to take care of the OOBE for C2K Mobile with 5
MHz frequency offset is - 58.5 - (- 116) = 57.5 dB
•
As per the 2 slope path loss model, we can get this 58.6 dB of path loss with ~10 m
from the mobile transmitter antenna
– Hence, from OOBE point of view also, there is no interference problem from
WCDMA UE transmit signal to C2K MS receive if 10 m separation is maintained
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WCDMA Handset Tx affecting CDMA Handset Rx:
Summary
• From the RF blocking of the C2K MS receive by the WCDMA UE
transmit signal point of view
– with 3.85 or 5 MHz C-C frequency spacing of carriers, around 1 m
mobile separation is required
• From OOBE interference on the C2K MS receive by the WCDMA UE
transmit signal point of view
– with 3.85 or 5 MHz C-C frequency spacing of carriers, 10 m
separation is required
– Under 3.85 C-C frequency spacing, with <10 m , there will be C2K
Forward Link capacity degradation
• Hence, with < 10 m mobile separation and 5 MHz C-C frequency spacing
of carriers, there will be very negligible C2K DL capacity degradation
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Field Trial in India to demonstrate co-existence of
WCDMA and CDMA
 CDMA frequency for testing : UL:1900-1910 MHz / DL:1980 - 1990 MHz (10+10 MHz)
 WCDMA frequency for testing: UL:1920- 1980 MHz / DL:2110 -2170 MHz (60+60 MHz)
 Guard Band between CDMA and WCDMA(edge to edge): 2.5MHz,3.75MHz,5MHz(Based on
test cases)
 Distance between WCDMA and CDMA 2000 sites is 200m / 500m /1km based on test cases
 Filtering attenuation in CDMA Tx and WCDMA Rx paths
 CDMA Tx path: 60dB
 WCDMA Rx path: 40dB
 Antenna space isolation between CDMA and WCDMA BTSs: 50-60dB
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Deliverable after Field Trial Test Result
 Policy framework for deployment of 3G services using WCDMA/CDMA
technology in 1900MHz band.
 Mitigation of capacity loss / Quality degradation of WCDMA/CDMA
network due to cross technology interference.
 Guard band requirement between CDMA and WCDMA for coexistence 1900MHz band.
 Additional filter attenuation requirement in CDMA TX path and
WCDMA RX path for co-existence.
 Antenna isolation requirement between CDMA and WCDMA BTS.
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Conclusion

WCDMA(1920-1980 MHz for Node B reception) and CDMA(UL:19001910MHz/DL:1980-1990 MHz) CAN co-exist in India under the following
easy-to-achieve conditions:

An edge-to-edge Guard Band of min 1.3MHz using suitable filter in
the CDMA Tx path and WCDMA Rx path.

60dB antenna isolation between CDMA and WCDMA BTS.

10 meters separation between WCDMA and CDMA mobile or 10% DL
CDMA capacity degradation with 3.85MHz(GB=1.3 MHz) C-C
separation.
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SUGGESTIONS
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(1) Allocate additional 800 MHz (5 MHz from
889-894)
(2) Allocate 1900 MHz for existing expansion
as well as 3G services
(3) Allocate appropriate spectrum and Allow
flexibility to operators to provide any service
suitable to their requirements and as per the
licence
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(1)
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Additional spectrum in 800 MHz
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How to get Additional Spectrum in 800
MHz Band
Two ways to increase spectrum in 800MHz
Increase it from
20+20mhz
to
25+25mhz
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Reconsider allocation to
BSNL /MTNL
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Present Allocation in 800 MHz
Present Allocation in 800MHz
International
India
824-849MHz / 869-894MHz
(25+25 MHz)
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824-844MHz / 869-889MHz
(20+20 MHz)
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Increase 800 MHz bandwidth from 20+20 MHz
to 25+25 MHz– How to achieve?
• In India: 844-849 (5MHz)not allocated- wasted
• Why : corresponding downlink portion (889894MHz) is earmarked for GSM.
• Path forward: shift GSM from this portion to
DCS 1800 MHz band
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Issues in shifting GSM to DCS 1800
MHz band
Arguments For :
• CDMA operators have no other option- GSM operators have
the option to go to 1800MHz band
• Known and established Compatibility between 900 and 1800
MHz
• More than enough spectrum is available in 1800MHz band
• Even presently this portion of 900 MHz band (889-894) is not
available to GSM operators at many places
• TRAI recommended this portion to be vacated from existing
users and be allocated to the 4th cellular operators who have
frequency in 1800 MHz band only which is against the license
conditions of 4th Cellular operators [TRAI Reco of 13th May
2005 on Spectrum Related Issues para 3.5.4 at pages 69 & 70]
Arguments Against :
• No argument
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Reconsider allocation to BSNL/MTNL
•
No reservation for BSNL/MTNL for the future.
•
In GSM no. of subscribers of MTNL as on 30.6.06 is 2.17 Million and for CDMA
about 1.5 lakh (Delhi + Mumbai).
•
They have 4 CDMA carriers (5+5Mhz) in Delhi and Mumbai for less than 2 lakhs
subscribers!
•
Similarly in case of BSNL the GSM subscribers are 18.3 Million (all India) and for
CDMA the number is about 2.6 Million (all India)
•
Both BSNL&MTNL are concentrating on GSM and blocking spectrum for CDMA
•
Both are not even entitled for 4 CDMA carriers since they are also using corDECT and according to the licence conditions those using cor-DECT are entitled
for only 3 carriers in CDMA band.
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(2)
– Allocate 1900 MHz for expansion of existing
network as well as for 3G services
– Consider the utilisation of cor-DECT frequencies
in India - occupies crucial portion of 1900 MHz
PCS band {1880-1900MHz}
– In metro and large urban areas wherever corDECT is not used.
– This spectrum is wasted
– Reconsideration required.
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Suggested Spectrum Allocation
800 MHz Band
CDMA
1
800
2
3
4
824 - 849 / 869 - 894
5
6
7
8
824 - 849
9
0
869 - 894
1900 MHz Band
CDMA
PCS
1900
1
2
3
4
5
6
7
1880 - 1910 /
1960 - 1990
1900 MHz Band
8
9
0
1880 - 1910
1
2
3
4
5
6
7
8
9
0
1960 - 1990
*Wherever Cor-DECT frequency is not allocated
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(3)
– Allocate appropriate spectrum and allow flexibility
to operators top provide any service suitable to
their requirements
– Licence is :
• Technology neutral
• Permits voice and data services
• Permts all services which dio not require a separate licence.
– Within the allocated spectrum allow operators to
use all evolving technologies.
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Spectrum for Wi-MAX
• 2300-2400 MHz, 2500-2690 MHz, 3300-3800MHz and
for Wi-MAX applications.
• Not to consider 700 MHz for Wi-MAX application.
• Minimum assignment of 21 MHz contiguous band.
• Make available sufficient spectrum for Wi-MAX & priority
allocation be given to existing UASLs on circle basis.
• Pricing mechanism for Wi-MAX should be:
– Levy of revenue share as is done for access providers.
– Amount should be <1% to cover the administrative cost.
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Thank you!
Contact us at: [email protected]
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