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Thursday, September 15, 2011

Clearwire's $600 Million LTE Project will upgrade 66% of Clearwire's Sites

From Hope Cochran's presentation for the Bank of America - Merryl Lynch Media, Communications & Enterainment Conference 2011, Clearwire will be upgrading 10,000 of their 15,000 cell sites once they raise the necessary capital.  Hope stated 2/3 of their sites.  The capital would be spent on both core and radio access network equipment.  Each of their existing RAN vendors, Motorola, Samsung, and Huawei has a different path to LTE Advance, some only requiring a card swap, and some requiring a radio addition.

Monday, August 29, 2011

CTO explains Clearwire's unique flavor of LTE

CTO explains Clearwire's unique flavor of LTE

This interview with Clearwire's Chief Technical Officer clears up the LTE Advanced questions but leaves open the question of how many cell sites would be upgraded to LTE for $600 million.

Monday, August 15, 2011

How valuable is the rural data coverage provided by satellite?

Here is an excerpt from the Genus Smartphone user guide on establishing a satellite connection.
It doesn't say much about the ability to use the data service in-building....

Terrestar Genus: Establish a Satellite Connection

Friday, August 5, 2011

TD-LTE - What has been happening?

What has the TD-LTE Industry been doing while Verizon and AT&T have dominated the LTE discussions with their FDD-LTE deployments?  See the link below to see the industry briefing provided by the Global TD-LTE Initiative (GTI) organization.  On Wednesday's earnings call, Clearwire aluded to being a member of GTI along with China Mobile and Vodofone.  This briefing details testing of tunable MIMO antennas and the availability of multimode multiband user devices.

TD-LTE Industry Briefing - May 2011

A couple of other interesting points from the report.  AT&T was a presenter on the multimode multiband LTE user devices.  This makes sense since the report makes it clear that the international focus on TD-LTE is in the 2.3GHz and 2.5GHz band.  AT&T is a significant holder of the US WCS spectrum.  The WCS spectrum consists of 3 paired 5MHz channels that bookend the DARS (Digital Audio Radio Service).  If a carrier controlled all 3 pairs channels, they would be capable of having a two carrier system using 15MHz channels.

Sprint Network Sharing Deal with Clearwire

With the recent announcement of a network sharing deal between Sprint and Lightsquared, the media is now pressing for a deal to have Clearwire spectrum operate from Sprint sites as part of their Network Vision.  Sprint has done a great job of spinning that the WiMax network their devices operate is engineered, constructed, owned, and operated by them.  This often gets confused by the ownership interest that Sprint has in Clearwire. I think a model that represents this well is the joint ownership of a home.  Sprint, Comcast, Google, Time Warner,  Brighthouse, Intel, and Eagle River all have invested in this "home".  The "home" has its own budget and makes its own decisions (through the board of directors).  Obviously, decisions take the interests of each of the home owners into account but the board of directors is only required to make this the best "home" that it can be.

There are many partial truths that are circulating among the press and analyst opinions.  Below are a few:

  • Clearwire's network is Sprint's.  The WiMax radio and core network is entirely engineered, constructed, owned, and operated by Clearwire.  Each of the "home" owners customer traffic as well as other MVNO partners (Best Buy, Locus, Cbeyond, and Mitel) is routed from Clearwire's network each each of these partner's networks.
  • Sprint has the core skills to operate a 4G backhaul network.  It is clear that with the struggles that Dragonwave has in attracting new domestic customers, the four national wireless players don't value microwave as a backhaul solution for cell site data traffic, and lack experience in operating this portion of the all IP network.
  • As Clearwire stated on their investor call yesterday, only 40% of their 16,000 cell sites are located at the same sites that Sprint operates from.  These would be the only locations that have access to 4G backhaul and it only backhauls to the WiMax switching location, not to a location that Sprint controls.

Attached is a photograph from Sprint's Network Vision webpage.  The top picture shows a 4G site (the short cabinet on the left) co-located with a Sprint 3G site.  In this picture Sprint and Clearwire appear to be separate tenants of the tower owner since they don't appear to be sharing any common elements (power systems, cables, ground space, backhaul, or antennas.)

Wednesday, July 27, 2011

Wireless Data Plan Comparison

Well, here is the truth on 4G data plans, thanks to Sprint.  It shows it all:  
  • Increased cost after 2G a month for AT&T and Verizon
  • Slowing to EDGE speeds on T-Mobile after 2G (Still unlimited though)

Tuesday, July 26, 2011

Sprint Network Vision

Is anyone else wondering why Sprint is upgrading their CDMA network and Verizon isn't?

Thursday, May 19, 2011

4G Applications and Services Update

In this paper, we are going to describe the current environment for 4G applications and services.  These would be defined as services and applications that drive 4G adoption and usage.  Primarily we will focus on services for tablets and mobile handsets. 

With 4G services typically ranging at 3Mbps or higher, most of your typical home or office connectivity needs can be met with a USB styled device or internal wireless card.  As long as you are not concerned with the download limitations of your service provider, you can download and upgrade software programs for your laptop on the go and purchase downloadable movies and music just like you would on your home wired service (cable, fiber, or DSL).  Our point of comparison is our 12Mbps/2Mbps cable modem service typically runs between 3-4Mbps in the evening when the network is loaded.  The only reason to queue traffic to be done on your home (wired) network would be due to usage (tonnage) concerns.

Primarily the services and applications that demand and utilize mobile 4G speeds, fit into 4 categories:
  1.         Video Conferencing
  2.         Live Content – Cloud Streaming
  3.         Live Content – Relayed Streaming
  4.         Queued Content – Cloud Streaming

Before we examine each of the services, we need to examine the speeds necessary for these 4G services to operate with an acceptable consumer quality.  All of the streaming video applications that we have tested, peak at about 2Mbps for maximum quality either on an iPad, mobile handset, or PC.  On our 802.11n WiFi network (capable of more than 100Mbps), the video streams are limited within the applications to not exceed 2Mbps.  Since the required speeds for these applications is well within each of the 4G network’s capabilities (HSPA+, LTE(FDD), and WiMax), we believe that too much focus is being diverted to the peak speeds that a network delivers, rather than whether that network will allow the user to use the 4G applications to truly unwire the internet experience.  To recall, cellular voice service adoption increased once carriers included large enough buckets of minutes so the user could take their eyes off the minute meter and truly unwire their voice usage.  The same will be necessary on mobile 4G data.  None of these services are going to unwire if we can only use them 4 or 5 times a month before we start bumping against a usage cap  requiring either the purchase of additional bandwidth (Verizon Wireless or AT&T), or being throttled (artificially limited) to EDGE speeds (300kbps) if the user is a T-Mobile customer beyond their 2G monthly limit.  Either unlimited or much higher usage limitations must be in place before consumers will begin to use their mobile 4G services for the entertainment and business services we discuss below.

Speed Tests:
All of the demonstrations that are presented in this article took place at an office location .4 miles from the tower which supports both Clearwire/Sprint’s WiMax network and Verizon’s LTE network.  This test location would be considered a strong RF environment for both networks.  To characterize how each of the 4G networks is operating, we performed a speed test on each of the devices and the 4G network it was operating on.

In this demonstration, the Evo on Sprint’s downloaded at 8.33Mbps and uploaded at .98Mbps.  The Thunderbolt on Verizon’s network downloaded at 7.74Mbps and uploaded at 31.53Mbps. The PC on Clear’s network downloaded at 9.39Mbps and uploaded at .79Mbps.  The Clearwire and Sprint WiMax network is capable of upload speeds greater than 1Mbps, but each carrier limits the upload bandwidth at 1Mbps.

iPad connected to Clear via a ClearSpot 4G: 

Examination of 4G Services and Applications:
To examine each of these services, we will first discuss the framework of how the service is delivered and then provide a link to a video demonstration of the application running on one or more 4G networks.  We consider the Sprint and Clear WiMax networks to be two different 4G networks.  Although both networks utilize the same cell site base stations and backhaul network, each company has different customer offerings that may affect the actual user performance.  In fact, running a simple trace route command indicates that Sprint and Clear each take their market traffic to the internet over different pipes, so their system results will be different. 

Video Conferencing:
Video conferencing to portable devices is still in its stages of development.  One of the reasons for slow adoption is the lack of tie-in with existing video conferencing providers, namely Skype.  Skype is used extensively as a PC video conferencing application with the 45 and under crowd, especially amongst high school and college students.  When the Sprint Evo 4G was first released, we attempted for over 8 hours to get it to work with a Skype PC users contacts list.  A Skype app was not available for Android yet, so we used the fring application which allows you to connect to Skype users, without success.  Skype is developing a video conferencing app for Verizon, but the version for all other carriers will not include the video conferencing capability.  Video conferencing connections were supported by the Evo but it was with the on board Qik application and could only connect to another Evo with the Qik application.  In the meantime oovoo has released an application for android that enables portable devices to connect to their existing PC user base.  In our demonstration we created a three-way video conference between an Evo, Thunderbolt, and PC.  As you can see from the video, there are compatibility issues with the Thunderbolt which prevented the front facing camera from being used for the video conference.

Demonstration of oovoo video conferencing:   

As the video demonstrates, handset and PC video conferencing is absolutely available today on 4G networks with oovoo.  The shortfall with the oovoo application is its lack of reach into the living room so a consumer could connect from their living room TV, their PC, or their handset with the same application and login.  The living room environment is developing slowly, with Logitech providing video conferencing to GoogleTV set top boxes and with Skype building their application into a very limited number of web enabled televisions.  Microsoft is rumored, even prior to its Skype purchase offer, to be developing video conferencing solutions through the Xbox360 platform.  With all of these options the key component to success will be an application layer across the living room, personal computer, and handset devices that provides a singular login and seamless ability to determine if your contacts are available and can be easily connected to a video conference.

Live Content – Cloud Streaming:

Since a majority of the current 4G applications and services involve video streaming, we have broken down the categories by the type of content and the source of the streaming video.  The sources of video streaming are cloud, relayed, and home media sourced.  The types of content will include live and queued content.  The primary limitation in streaming live content from the Cloud is the required match between the consumer device application and the available cloud video content.  Here is an example: NCAA March Madness content was accessible using iPhone/iPad directly from the internet with an application from the Apple App Store.  Direct streaming of this content was not available to any Android, WebOs, Windows Phone, or Blackberry devices.

Demonstration of NCAA March Madness on an iPad on Clear:

Demonstration of NCAA March Madness on an iPad on Sprint 3G:

A similar application is MLB at Bat 2011.  Rather than providing statistics and live video feeds just for a tournament, this application provides statistics and live video feeds for each game of the entire Major League Baseball season.  In addition, this application has both iPhone/iPad applications as well as Android, and web based streaming capabilities.

Demonstration of MLB at Bat – 2011 on a Sprint Evo 4G:

Demonstration of MLB at Bat – 2011 on an iPad on Clear:

The final live video streaming application is Ivy TV.  Ivy TV is a Windows PC application that provided access to all of the broadcast television channels in New York, Los Angeles, Chicago, and Seattle.  The video was accessed using a television guide similar to your cable or satellite provider’s guide.  The user can pause programming and there are plans in the works to provide recording capability and an application for handsets.  Ivy TV is currently reduced to a few educational channels because of a lawsuit over their rebroadcasting rights, but we are highlighting the service here because it demonstrates what the available technologies can accomplish; unfortunately, in this case the technology is limited by the media rights.

Demonstration of Ivy TV:

The last applications in this group are live streams that play in a Flash player.  These could be sports games, news clips, and video games.  Android and WebOs browsers support videos and games that play in flash.   Blackberry, iOS, and Windows Phone browsers still lack Flash support.

Live Content – Relayed Streaming:

Relayed Streaming applications typically require that the video content is delivered to the consumer at their home and then the content is rebroadcast to mobile devices.  This methodology resolves the media licensing issues, but it puts additional delay into the system and limits the streaming speeds to the uplink speed that the customer has from their home.  In this category, we are including Play-on TV, Slingbox, and TV Everywhere.  Play-on TV is a monthly service that provides access to Netflix, MLB, NHL, NFL, Hulu, ESPN3 and many other free and subscription channels.   Play-on TV has device applications for Android and iPhone/iPad devices.  Slingbox and TV Everywhere are both applications that are based on the Slingbox technology.  Slingbox enables the consumer to control their cable or satellite set-top box and stream the output of the set top box, either live video or a DVR (digital video recorder) video, out to the internet for remote viewing.   TV Everywhere is a Dish Network product that uses the Slingbox technology, integrated with their satellite receivers.   The primary difference between the two applications of the Slingbox technology is that the Slingbox technology requires mimicking remote control keystrokes to control the DVR from a remote location, while TV Anywhere product provides direct control across the internet.  Play-on TV is supported on Android and iPhone/iPad devices.  TV Everywhere is supported on Android and iPhone/iPad devices and is beta for Blackberry devices while Slingplayer is supported on Android, iPhone/iPad, Blackberry, and Windows Phone.

Play-On TV Host Setup:

Demonstration of Play-on TV NCAAA March Madness on an iPad:

Demonstration of Play-on TV ESPN3 on an iPad:

Demonstration of Play-on TV Netflix and NCAA March Madness on a Sprint Evo 4G (Android):

Demonstration of Play-on TV ESPN3 on a Sprint Evo 4G (Android):

Demonstration of Slingbox with an iPad on Clear:

Demonstration of TV Everywhere with an iPad on Clear:

Comparison of Slingbox on a Sprint Evo 4G with TV Everywhere on a Verizon Thunderbolt 4GLTE:

Queued Content – Cloud Streaming:

This category of video streaming provides stored video content to be streamed from a cloud location.  The stored video content can be previously recorded sporting events, movies, and TV shows.  The most well-known providers of this content are Netflix and Hulu.  Netflix has an application for the iPhone/iPad, Window Phones, and an application for the HTC Android phones was released last week.  Prior to the Android app release, you could play Netflix content on an Android device using the Play-on TV application.  Hulu only has an application for the iPhone/iPad at this time.

Comparison of Netflix on an iPad on Clear and an Evo 4G on Sprint utilizing Play-on TV:

As you can see in the demonstration, cloud streaming presents a much better user experience by delivering the desired movie to the screen much quicker and with fewer user interventions (screen touches).

Demonstration of Netflix on an iPad on Clear:


In the attached report, we explored two areas that will drive 4G adoption; applications and the service requirements.  We concluded that too much focus is being spent determining which network is the fastest, since all of the current video conferencing and video streaming applications run at 2Mbps or less for maximum quality.  The key differentiator for 4G adoption is having enough bandwidth (tonnage) to run the 4G applications and services that users desire for an entire month without needing to count the bits or change the desired usage behavior.  Next, we provided demonstrations of the key applications and their delivery methods.  We demonstrated video conferencing applications utilizing 4G networks, services providing live video from the cloud to mobile devices, services providing live video relayed through a home setting to mobile devices, and services providing queued video from both the cloud and relayed through a home setting.  From these demonstrations, we concluded that delivering services directly from the cloud provided the best performance, but it required that specific applications (Netflix) be written for hardware platforms (Android).  There are a few applications, Play-on TV, Slingbox, and TV Everywhere, that resolve the media license rights by delivering the legal content to your home, then relaying it out to their mobile applications.  This is a good interim solution, but it increases the delay and increases the complexity, and subjects the service quality to the typically uplink-limited capacity at the user’s home.

Saturday, April 23, 2011

4G Spectrum Investigation

Attached is a spectrum report for Seattle, Washington, focusing on the spectrum band currently utilized for mobile voice,  3G data, and 4G data.  We are using this market to develop an understanding of the way spectrum ownership affects the ability for a carrier to deploy 4G technologies. The spectrum bands covered include: 700MHz, Cellular, 1.4-1.6GHz satellite,  Personal Communcations Services (PCS), Advance Wireless Services (AWS), Wireless Communications Services (WCS), Broadband Radio Service (BRS), and Educational Broadcast Service (EBS).  The outcome of the analysis in this report details the amount of spectrum that each of the current carriers have available for 4G broadband services.  This report focuses on each carrier’s spectrum ownership, not whether the spectrum is currently loaded with either voice or data services.

Band Construction:
To build this report, information on each of the band configurations was gathered from the FCC website.  Using this information it is easy to see what channel blocks are contiguous, and how the existing spectrum ownership can be converted over time to 4G spectrum operation.  For the purpose of this report, we have only considered the adoption of 10MHz carriers for 4G.  The frequency division duplex (FDD) version of LTE can be operated in paired channel bandwidths of 1.25MHz, 5MHz, 10MHz, 15MHz, and 20MHz.  Currently, LTE only has commercial implementations in 5MHz (MetroPCS) and 10MHz (Verizon Wireless).    Users are reporting 3G type speeds on the MetroPCS network (700kbps download), so we consider 10MHz a minimum channel bandwidth for 4G services.

4G Spectrum Bands
Frequency Band
Starting Frequency
Ending Frequency
Advance Wireless Services
Personal Communications Services
Wireless Communications Services
Broadband Radio and Educational Broadcast Service

Spectrum Ownership:
Spectrum ownership was determined for each channel block using the FCC’s Universal Licensing System (ULS) market based license search, with the geographic boundaries of King County.  Each active licensee in one of these spectrum blocks was translated to the appropriate major carrier name and the licensed spectrum information was logged on Appendix A.   If a lease was indicated within the FCC ULS records, the corresponding spectrum was allocated to the controlling carrier.  This predominantly affects the EBS spectrum used by Clearwire.   The PCS spectrum blocks have been broken down, consistently, into 5MHz blocks to account for the reauctions and spectrum trades that have broken the original auction spectrum blocks into smaller pieces.  It is important to note that virtually the entire spectrum covered in this report has been configured as paired spectrum, which would typically be put to use in a Frequency Division Duplex (FDD) system like LTE(FDD).  There is 42MHz of unpaired spectrum in the EBS/BRS band which is not paired, leaving a Time Division Duplex (TDD) system as the only current 4G option.

The analysis is fairly straight forward.  The columns on Appendix A are essentially roads of exclusive spectrum ownership or control.  For each 10MHz of contiguous spectrum, a carrier was allotted one - 4G carrier.  In the current LTE implementations, the same 4G carrier is assigned to each of the three sectors on a typical cell site, thus a carrier with only one 4G carrier available could complete a market-wide deployment using that carrier, but they wouldn’t have any spectrum to deal with data capacity issues across their network.  Any high usage areas would require the permitting and construction of a new site to offload the existing network capacity. 
Lightsquared has a shared licensing interest for the 1.5/1.6GHz frequency band.  We have indicated a maximum number of 4G carriers that could be defined within this mobile satellite band.  This spectrum is frequency-coordinated between international operators and operators in Mexico and Canada and will require satellite receivers to be modified before wideband spectrum will be available.  In addition, the FCC is likely to require that a portion of this band be dedicated to satellite operation, making it unavailable for the contemplated Lightsquared terrestrial deployment.  Each of these factors makes it difficult to determine the final number 4G carriers Lightsquared will have available.  Since this is a spectrum exercise, Lightsquared’s dispute with the GPS community and the filed GPS interference issue is a noteable risk to the use of this spectrum, but doesn’t affect ownership.

Spectrum Available for a 10MHz 4G Configuration – Seattle (King County)
MHz that could be combined for 4G (FDD)
Number of 10MHz (FDD) Carriers (Paired)
MHz that could be combined for 4G (TDD)

As this data describes, there is very little spectrum available for 4G deployments.  Much of the spectrum that the carriers own is already deployed with the carrier’s existing voice and data technologies.  Verizon Wireless carries virtually all of its CDMA voice and data traffic in the cellular band with a small holding (5MHz) in the PCS band.  Verizon’s LTE deployment uses the 10MHz paired block that it has at 700MHz.  For Verizon to grow its LTE network to a second carrier of capacity, they would need to clear virtually all of the voice and 3G data traffic from the cellular band and then overbuild their entire network with cellular frequency radios, since today they only have the 700MHz frequency equipment in place.  In addition, all of Verizon’s LTE devices only work on the 700MHz band C block channels, thus, they would need to be swapped to operate on the additional bands, once constructed.  If spectrum acquisition is an option, only 20MHz of spectrum (AWS) is not in the control of a regional or national wireless player. 
Another example to understand is the effect of the  AT&T and T-Mobile merger.  The alignment of the spectrum in the Seattle market doesn’t create any additional 4G spectrum opportunities for AT&T than the companies had separately.  These opportunities would come from 5MHz spectrum pieces that align with the other carrier’s stranded spectrum.  While the merger will allow the combined company to have AT&T’s four  – 4G carriers plus T-Mobile’s two - 4G carriers for a combined six - 4G carriers.  They will be spread through five different frequency bands (four if you consider PCS and AWS to be similar in frequency to share cell site radios and antennas).

AT&T 4G Carriers
T-Mobile 4G Carriers
Total Carriers

Operationally, both T-Mobile and Verizon are going to have a more complex radio environment to optimize because of their use of multiple frequency bands, thus multiple radios, at their cell sites for their 4G networks.  It is likely that the higher frequency sectors will need to hand their data calls to a lower frequency sectors before the data call is handed to an adjacent site.  Each of these handovers has to be optimized for vehicle and walking traffic or the customer will experience dropped packets or a data call failure.
The final area we analyzed is the ability of the carriers to grow to higher speed solutions.  To increase the speed from the existing 10x10 LTE(FDD) deployments will require stepping to a 15MHz or 20MHz channel solution, like 20x20 LTE (FDD).   In the Seattle market, AT&T and Sprint (owners of the MTA blocks of PCS spectrum) would be able to deploy a single 15MHz 4G carrier throughout the market.  Neither the 700MHz or Cellular bands have the spectrum bandwidth to deploy this broadband carrier.  In comparison, Clearwire’s spectrum position provides three -20 x20 carriers, operating in a paired configuration, between the EBS/BRS lower band and upper band. 

LTE Speed Comparisons by RF Channel Configuration

Frequency Band
Verizon Wireless Commercial Offer
FDD 10x10 (MHz)
Clearwire LTE Trial
FDD 10x10 (MHz)
Clearwire LTE Trial
FDD 20x20 (MHz)
LTE Theoretical Peak Rate (4x4 MIMO)

FDD 20x20 (MHz)

Appendix A – Seattle (King County) Spectrum Band Maps