Friday 30 September 2011

Macrocells or Metrocells?

Just went through Alcatel-Lucent strategic paper on whether to go for more Macrocell sites or rather have Metrocells instead.

A good description of Metrocells is available in the document:

Metro cells, the latest evolution in small cells, are based on the same low cost femtocell technology that has been successfully used in home and enterprise cells, but with enhanced capacity and coverage. With higher processing and transmit power, the first generation of metro cells is engineered to serve from 16 to 32 users and provide a coverage range from less than 100 meters in dense urban locations to several hundred meters in rural environments. However, unlike home and enterprise cells, metro cells are owned and managed by a MSP and typically used in public or open access areas to augment the capacity or coverage of a larger macro network.

Available in both indoor and outdoor versions, metro cells are plug-and-play devices that use Self-Organizing Network (SON) technology to automate network configuration and optimization, significantly reducing network planning, deployment and maintenance costs. While indoor versions use an existing broadband connection to backhaul traffic to a core network, outdoor versions may be opportunistically deployed to take advantage of existing wireline or wireless sites and backhaul infrastructure, such as Fiber-to-the-Node (FTTN), Fiber-to-the-Home (FTTH), Very-high-speed Digital Subscriber Line (VDSL) street cabinets, and DSL backbone.

Since metro cells use licensed spectrum and are part of the MSP’s larger mobility network, they provide the same trusted security and quality of service (QoS) as the macro network. With seamless handovers, users can roam from metro cells to the macro network and vice versa. Metro cells also deliver the same services as the macro network (for example, voice, Short Message Service (SMS), and multimedia services), and support application programming interfaces (APIs), that may be used for developing new, innovative services. In short, metro cells promise to be the ideal small cells for network offloading.

For more details on the whitepaper see: http://www.slideshare.net/zahidtg/metro-cells-whitepaper



Saturday 24 September 2011

Public training on UMTS and HSPA/HSPA+


We are conducting our first public training on UMTS and HSPA/HSPA+. There are still a lot of people working on UMTS / HSPA / HSPA+ even though quite a lot of focus is being put on LTE.

This course is split into 3 parts and the person attending it can decide which days he wants to attend. The intention is to bring a person with minimal knowledge upto a good speed and to a level where (s)he can become an expert by putting some extra effort.


Discounts available for regular readers of this blog. Please ask.

Tuesday 20 September 2011

Panel Session on Small Cells (Femtocells) from Cambridge Wireless SIG event

Panel Session on Small Cells (Femtocells) from Cambridge Wireless SIG event from Zahid Ghadialy on Vimeo.

From the Cambridge Wireless Small Cell Special Interest Group event


“Small Cells: the beginning and where we are now”

15 September 2011

At The IET, Savoy Place, London, WC2R 0BL


Panel Session

Chair: Mike Bowerman, Account Manager, Alcatel Lucent.

Participants (from Left to right):

Professor Will Stewart, IET

Houston Spencer, VP Solutions and Marketing, Alcatel-Lucent

Will Franks, CTO and Founder, Ubiquisys

Chris Cox, Director of Marketing, ip.access

More details about the speakers and the event available at: http://www.cambridgewireless.co.uk/Agenda/SCS1_15.09.11.pdf


Monday 19 September 2011

Summary from the 'Small Cells' Event in Cambridge Wireless

We recently had our first 'Small Cells' SIG event in Cambridge Wireless entitled 'Small Cells: The beginning and where we are now'. The following presentation is the Introduction to Cambridge wireless and the 'Small Cells' SIG (special interest group).


Embedded below are the slides and the videos that were taken by our host for the day, 'The IET'.

The first presentation was by Prof. Will Stewart of The IET entitled 'Small Cells - Why small cells?'.



Next presentation: 'Small Cells - the big brother of femtocells. Why they are needed, and where is the femtocell market that they build on' by Will Franks, Ubiquisys



Next Presentation: 'Small Cells - On the origin of Small Cells by means of natural selection, or the preservation of favoured providers in the struggle for mobile broadband' by Houston Spencer, Alcatel-Lucent



Final Presentation: 'Small Cells - Mass scale femtocell deployments' by Chris Cox, IP.Access



Overall it was a good event. The main complaint was that people had lots of questions but didnt get to ask them. Hopefully they will ask them in the future events.

Wednesday 14 September 2011

Inter-technology Carrier Aggregation

Another one from the 4G Americas whitepaper of Mobile Broadband explosion:

Carrier aggregation will play an important role in providing operators maximum flexibility for using all of their available spectrum. By combining spectrum blocks, LTE-Advanced will be able to deliver much higher throughputs than otherwise possible. Asymmetric aggregation (i.e., different amounts of spectrum used on the downlink versus the uplink) provides further flexibility and addresses the fact that currently there is greater demand on downlink traffic than uplink traffic. Specific types of aggregation include:

  • Intra-band on adjacent channels.
  • Intra-band on non-adjacent channels.
  • Inter-band (e.g., 700 MHz, 1.9 GHz).
  • Inter-technology (e.g., LTE on one channel, HSPA+ on another). This is currently a study item for Release 11. While theoretically promising, a considerable number of technical issues will have to be addressed.

Tuesday 13 September 2011

CELL_FACH to LTE Mobility

At the moment, transition from RRC states from UMTS to LTE can happen from CELL_DCH to E-UTRA_RRC_CONNECTED state via Handover or from UTRA_IDLE to E-UTRA_RRC_IDLE via Cell Reselection. There is a study ongoing to transition from CELL_FACH to LTE. The state has not been specified but my guess is that it would probably be E-UTRA_RRC_CONNECTED. The following is the reasoning based on RP-111208:

It is our understanding that some of the Cell_FACH enhancement proposals for Release 11 are targeted to make it more attractive to keep UEs longer in the Cell_FACH state than is expected with pre-Rel-11 devices. This expectation that the UEs may stay longer in the Cell_FACH state is in turn motivating the mobility from Cell_FACH state to LTE proposal.

For instance, as the network can already today release the Cell_FACH UE’s RRC Connection with redirection, network may want to redirect UE to the correct RAT and frequency based on the UE measurement. Specifically if the network strategy is to keep the UEs long time in Cell_FACH state, it would make sense to provide the network the tools to manage the UEs’ mobility in that state. In addition, the needs for mobility to LTE are somewhat different from mobility to e.g. GERAN, as the former would be typically priority based while the latter would happen for coverage reasons. Thus, if introduced, the network controlled mobility from UMTS Cell_FACH would be specifically interesting for the UMTS to LTE case.


Will update once I have more info.