UMTS/LTE in 800 MHz for Europe

800MHz band (also known as 790-862 MHz, channels 61 to 69 in UHF Bands IV and V) was previously used by analog broadcasting, and is particularly suitable for delivery of high-bandwidth services and indoor coverage.

UK regulator Ofcom is pushing to clear the 800MHz band of existing and previously planned users and align the upper band of the UK’s digital dividend with the spectrum being identified for release by an increasing number of other European countries. The reason behind this move is that this spectrum is likely to be particularly suitable for the provision of a new generation of mobile broadband services.

A 3GPP work item is currently under works to provide specification for "UMTS/LTE in 800 MHz for Europe" to provide support for LTE and UMTS with paired channel arrangement in the band 790-862 MHz.

Based on 3GPP work item the 790-862 MHz band is arranged as 2x30 MHz with 11 MHz duplex gap:

• FDD Uplink: 832 – 862 MHz
• FDD Downlink: 791 – 821 MHz

The tasks identified by 3GPP in this work item includes, study of UMTS/LTE in upper UHF band for a potential deployment in ITU Region 1, generate a new technical report based on study results and develop channel arrangement in line with the pending ECC decision.

The target date set by the EC for analog switch-off in EU member countries is 2012. Finland, Sweden, France, Switzerland, Germany, Spain and Denmark have already decided to release the whole of the 800 MHz band, with others likely to follow. More speed is both necessary and desirable to fully realize the benefits.

The State of 3G and LTE in India

With wireless subscription having reached to 441.66 Million, India has yet to catchup with other countries in 3G and LTE (Long Term Evolution) deployments. India's state-run mobile operators BSNL and MTNL have already launched commercial 3G services after getting access to spectrum last year. BSNL and MTNL have set sights on adding between 200,000 and 300,000 subscribers during the first year of operations.

DoT and finance ministry recently indicated to limit the number of slots to just four blocks of 5 MHz each in the 2.1 GHz band for 3G auctions with a view to maximizing revenue per block of spectrum. These four new entrants will be in addition to BSNL/MTNL, taking the total 3G operators per circle to five.

Even as the policy for auctioning spectrum for 3G mobile services is yet to be finalized, the Department of Telecom is already thinking about the introduction of 4G technologies such as LTE. It says some spectrum must be retained to accommodate the future needs of these operators as well as to provide for 4G technology (LTE) which will require a minimum channel of 10 MHz for the launch of service.

However telecom operators RCOM, Tata, Systema and equipment vendor Qualcomm strongly are opposing the government’s move to restrict 3G spectrum auctions to four blocks per circle. These companies want all spectrum to be put on the block so that the demand-supply equation pushes down its price.

The final decisions will be made by Empowered Group of Ministers (EGoM) in the next few weeks, based on which 3G auctions are expected either by early December or after January 2010.

It is still not clear how many operators could get 3G & LTE spectrum. Similar to 3G, LTE may come in India in 2.1 Ghz band, as 2.5 Ghz (EU LTE spectrum) is mostly used for satellite-based networks. In India most operators are looking to move to this technology by 2011, once they start making money on 3G services. MTNL & BSNL may again lead LTE deployments.

LTE Advanced: Evolution of LTE

LTE standards are in matured state now with release 8 frozen. While LTE Advanced is still under works. Often the LTE standard is seen as 4G standard which is not true. 3.9G is more acceptable for LTE. So why it is not 4G? Answer is quite simple - LTE does not fulfill all requirements of ITU 4G definition.

Brief History of LTE Advanced: The ITU has introduced the term IMT Advanced to identify mobile systems whose capabilities go beyond those of IMT 2000. The IMT Advanced systems shall provide best-in-class performance attributes such as peak and sustained data rates and corresponding spectral efficiencies, capacity, latency, overall network complexity and quality-of-service management. The new capabilities of these IMT-Advanced systems are envisaged to handle a wide range of supported data rates with target peak data rates of up to approximately 100 Mbit/s for high mobility and up to approximately 1 Gbit/s for low mobility.

In order to meet this new challenge, 3GPP widened its scope to include systems beyond 3G. LTE Advanced would fulfil the 4G requirements as set by ITU. In 2008 3GPP held workshops on IMT Advanced, where the “Requirements for Further Advancements for E-UTRA” were gathered. The resulting Technical Report 36.913 has been now published.

Let us see some requirements which differentiate LTE & LTE Advanced.

Peak data rate:

• LTE - DL: 100 Mbps, UL: 50 Mbps
• LTE Advanced - DL: 1 Gbps, UL: 500 Mbps

Transmission bandwidth:

• In comparison to LTE, LTE Advanced is wider than approximately 70 MHz in DL and 40 MHz in UL.

Latency:

• LTE - C-plane from Idle (with IP address allocated) to Connected in <100>
• LTE Advanced - C-plane from Idle (with IP address allocated) to Connected in <50>

Peak spectrum efficiency:

• LTE - DL 3 to 4 times Release 6 HSDPA , UL - 2 to 3 times Release 6 Enhanced Uplink
• LTE Advanced - DL 30 bps/Hz and UL 15 bps/Hz.

C-plane capacity:

• LTE - At least 200 users per cell should be supported in the active state for spectrum allocations up to 5 MHz.
• LTE Advanced - At least 300 active users without DRX in a 5 MHz bandwidth.

Mobility:

• LTE - Support mobility across the cellular network for various mobile speeds up to 350km/h (or perhaps even up to 500km/h depending on the frequency band).
• LTE Advanced - Same as that in LTE, System performance shall be enhanced for 0 to 10km/h

LTE Advanced would operate in spectrum allocations of different sizes including wider spectrum allocations than those of Release 8 to achieve higher performance and the target peak data rate, e.g. up to 100 MHz.

3GPP Extended UMTS/LTE 800 Technical Report

3GPP has recently published a technical report of the Extended UMTS/LTE 800 which provides UTRA and E-UTRA specification support for FDD in the Extended 800 MHz band in Japan.

As a frequency re-arrangement plan in 800MHz band of Japan before and beyond year of 2012, the lower part of the band (UL:815 - 830 MHz / DL:860 - 875 MHz) was allocated to cdma2000 and the upper part of the band (UL:830 - 845 MHz / DL:875 - 890 MHz) was allocated to UMTS. To take it into account the latest frequency arrangement above 3GGP has proposed to introduce a new frequency band for UMTS.

3GPP Technical Report indicates that there is high possibility that not only UMTS but also LTE would be introduced in Japan in the band near future in order to enhance frequency efficiency. To accommodate it corresponding necessary work to introduce new bands for LTE is proposed by 3GPP.

The tasks included in proposed work item are to study of Extended UMTS/LTE 800 for a potential deployment in Japan, generate a new technical report based on study results and

study signalling issues related to Extended UMTS/LTE 800.

The specific bands studied by 3GPPare:

Band 18 for LTE:

• 815 - 830 MHz: UL
• 860 - 875 MHz: DL

Band XIX for UMTS/ Band 19 for LTE:

• 830 - 845 MHz: UL
• 875 - 890 MHz: DL