Femtocells have always intrigued me, why don’t we have more of them? They provide indoor coverage to customers like me, and many advantages to the operator. So why are operators not giving them out for free with a DSL connection like Softbank in Japan? This is the ‘new’ paradigm for indoor coverage, last frontier not conquered by the wireless providers. In the US we have so much fiber underground that most operators can run fiber-to-home (FTH) and put up a Pico cell, albeit the Capex costs. I would think the only thing that is preventing the deluge of femtocells is the pricing, operator initiative and certain other factors like Interference mitigation, etc. Let us explore what they are, how they can be overcome and a balance between performance and efficiency. Read more…
The media is on fire talking about how Google has surrendered the net-neutrality pledge and gone with the carriers, but there are technical reasons how it is the carrier-way or the highway. FCC last year set forth three rules – Providers can’t favor their own content, Providers need to explain variable speeds and Providers cannot limit access to lawful content, which Comcast had it overturned in court. Though FCC might posses the power to make rules on net-neutrality, albeit it is the technologies that control the flow of traffic which will decide how much of content delivery is neutral after all! Read more…
Broadband is re-defining the way technology is being deployed and who is playing a major role. The operators of the yore like – AT&T, Verizon are slowly giving way to spectrum holding partnerships like – Clearwire, Harbinger, etc. Cellular services are getting commoditized and networks of the future will become dumb pipes, through which services instead of just voice and data will be optimally delivered based on tiered pricing and Quality of service. Pay per minute and pay per megabyte will become a delivery mechanism for many operators, as user habits keep changing. Subscribers have become content generators from content consumers with social networking and micro blogging; and with smart phones making a plethora of applications that make use of data pipes similar to PCs, the trend will only keep increasing. Read more…
Wireless today at a crossroads and has become a key enabler of future consumer products, with potential applications ranging from high bit-rate video conferencing and movie viewing to simple ‘house keeping’ tasks in domestic appliances. Radio systems have moved toward forming heterogeneous wireless networks (hetnets), collaborations of multiple radio access networks, which in some cases operate different radio access technologies, such as second- and third-generation cellular RATs, IEEE 802.x wireless standards, and so on. On the other hand, multimode reconfigurable user devices with the ability to choose among various supported RATs have become a reality, and devices and networks with dynamic spectrum access capabilities, allowing real-time sharing of spectrum resource usage among different systems, are a part of the radio eco-space today.
Every decade brings changes to the way wireless is delivered to the users, and this decade shall belong to the indoor coverage and related services for wireless. I call them service ‘enablers’, the means to deliver a positive experience to users. While the 4G standards battle rages on for LTE vs. WiMAX, only the ecosystem will decide which will the dominant technology for the next decade. Whichever technology wins, these enablers will be omnipresent to delivery these technologies. We are at a true convergence for wireless where telecom meets the smart grid, smart home, and where networks become a service. The aims of the Wireless Enablers work area are, to develop technologies to support interworking of networks and efficient and effective use of spectrum for inter-RAN communications. Enhanced operation of data delivery mechanisms (performance and mobility), reduced complexity in processing.
The great outdoors for cellular wireless has been conquered. RF has limitations for delivery of wireless indoors, and there is a limit to the number of sites that any operator can deploy, with zoning and other FCC/FAA restrictions in place. Though repeaters and DAS systems have been around for a while now, but their place in the world is relegated to where no Pico/Femto cell would be able to provide the capacity and coverage like inside tunnels or casinos etc. Pico cells have filled in the coverage holes for operators in a big way and have been around for a while, but that entails an OPEX for the operator (power/backhaul) and can only plug some indoor coverage holes for the operators. The big push would be for Femto cells, where operators have a big advantage of getting coverage without any OPEX. Both the 3GPP (LTE) as well as WiMAX Forum have published the Femto standards, and are aggressively pursuing its deployment.
By 2012, there will be 36 million shipments with an installed base of 70 million femtocell serving 150 million users.
Source: Pico Chip
LTE Femto Architecture
LTE HeNB – Release 8
Femto-cells or Home Node Bs have been a hot topic for quite some time since they offer benefits such as providing:
• Significant offload of traffic from regular base stations;
• Full coverage and high speed transmission at home;
• Better link quality; lower transmit power, higher performance;
• A single mobile device serving all purposes for the customer;
• Improved customer relations for the operator.
In 3GPP terms, LTE femto-cells are called Home Node B’s for HSPA and Home eNode B’s for LTE. With increasing LTE terminal penetration and fixed-mobile convergence, the expected demand for LTE Home eNodeBs is likely to provide attractive services and data rates in future home environments.
WiMAX Femto Architecture
WiMAX Forum Global Congress, Amsterdam – June 17th 2010 – The WiMAX Forum and the Femto Forum announced the publication of the first WiMAX™ femtocell standard allowing vendors to start developing standardized femtocells and associated network equipment based on the IEEE 802.16e radio interface and profiles. The WiMAX Forum aims to start certifying compatible products in early 2011 to guarantee efficient and effective interoperability between different vendors’ access points and core network equipment.
WiMAX femtocells cost-effectively enhance coverage and capacity inside buildings and in small outdoor areas as well as supporting advanced new services. The specifications incorporate a security framework that allows WiMAX networks to support a large number of access points via standard commercial IPSec based security gateways. This phase of specifications also contains simple Self Organizing Network (SON) capabilities to allow automatic configuration of large numbers of femtocells. Future revisions will further enhance the SON capabilities to standardize automatic interference management between femtocells and macro base stations.
SoftBank Corp. has started offering femtocells for free in Japan as it ramps up its national service this year, a move that could spur other operators to adopt the same model for the small home base stations.
Not only are Softbank’s femtocells offered for free, but so is the ADSL connection, when customers sign up to a two-year contract. Another twist in Softbank’s strategy is that the access points are configured for open access, which means that any Softbank subscriber within range of a femtocell can use it. Most femto services today are offered on a closed access basis, which allows only registered users to use the access point.
SDR – Software Defined Radio
Software Defined Radio (SDR) is a radio technology implementation using software, which will become ubiquitous and a key enabling technology for reconfigurable, reprogrammable processing devices for Radio Access. SDR is the centerpiece in the development of multi-band, flexible and smart base stations that can costeffectively evolve as the technology advances. The classic definition of SDR is having arrays of general-purpose processors running virtually all functions in software.
SDR will help in efficient radio resource allocation for opportunistic communications, Support co-existence of devices and standards and multi-mode terminal to concurrently support multiple data delivery mechanisms with enhancements to standards to improve capability.
SDR platform can simultaneously support multiple air interfaces on one frequency and is particularly focusing on the 900MHz GSM band, which many European nations are allowing to be reused for newer technologies, especially for rural coverage. Its Multi-carrier Transceiver (MC-TRX) radio module can be used to upgrade base stations, continuing to support 900MHz or 1.8GHz GSM, and add support for HSPA or LTE as required, or when the regulator permits.
An SDR solution can be leveraged for:
- Redefining the base station from one radio technology to another
- Deploying multiple radio technologies in one base station simultaneously
- To target GSM refarming, and its radio (BBU) swaps for technology upgrade paths
- CAPEX would be saved as there will be no need to acquire new sites
This is a silent revolution that is taking place among the Chipset manufacturers, Infrastructure Vendors and operators that will have far reaching consequences for adaptation of efficient technologies and help re-use the spectrum.
ZTE was one of the first vendors to launch a SDR base station that can be upgraded to LTE through a baseband add-on and a software upgrade. Several other vendors have followed and are now launching – or have already launched – SDR base stations. The form of SDR implementation in base stations varies and each vendor may have chosen a different level of commitment for software reconfigurability. ZTE and Huawei are the only vendors that support dual mode GSM/UMTS operation in their base stations, ZTE having released the platform first. However, dual mode SDR deployments have been limited to date and are now slowly entering the market.
M2M – Machine-to-Machine
M2M or Machine-to-machine communications is the next biggest boom for the wireless operators. There are now more than five billion connections worldwide. In many regions, penetration exceeds 100%, where there is more than one connection per person in the country, and for operators to get more net adds and to grow they have to look towards this segment. One of my first experiences was deploying SCADA devices in the Gulf of Mexico on Oil Platforms which sent readings to the control centers via GPRS/EDGE networks. But things have changed from then to now, where Air Interface has become more robust and the ‘data pipe’ has become fatter and more self sustaining. And On-Star devices on vehicles have become standard, for driver safety and tracking.
M2M has been around for a while but the cost, performance breakthroughs have come closer to reality, and the standards have been formalized. With a mobile voice market close to saturation in the all over the world, many operators are searching for new sources of revenue.
Key Elements of M2M Architecture
- A device capable of replying to requests for data contained within those devices or capable of transmitting data contained within those devices autonomously.
M2M Area Network
- Provides connectivity between M2M Devices and M2M Gateways. Examples of M2M Area Networks include: Personal Area Network technologies such as IEEE 802.15, SRD, UWB, Zigbee, Bluetooth, etc
or local networks such as PLC, M-BUS, Wireless M-BUS.
- Use M2M Capabilities to ensure M2M Devices inter working and interconnection to the communications network.
M2M Communications Networks
- Communications between the M2M Gateway(s) and M2M application (server). Can be further broken down into Access, Transport and Core networks. Examples include (but are not limited to): xDSL, PLC, satellite, LTE, GERAN, UTRAN, eUTRAN, W-LAN and WiMAX.
M2M Applications (Server)
- Contains the middleware layer where data goes through various application services and is used by the specific business-processing engines. A software agent or process by which the data can be analyzed, reported, and acted upon.
All standards organizations led by ETSI are working towards developing common architecture for M2M, as Multitude of technical solutions and dispersed standardization activities result in the slow development of the M2M ecosystem.
The leaders in M2M communications in the US market have been the traditionally the GERAN carriers – T-Mobile and AT&T, but Clearwire too has been playing the catching up game with WiMAX nationwide deployments. And Verizon and Sprint are also working with vendors for device certification and building middleware platforms for M2M services with platform vendors like Jasper Wireless & Sierra Wireless to integrate server and access-network resources. This space shall also be leveraged by the utility power and water companies along with healthcare monitoring service providers. KPN (KPN) a Dutch carrier is using CDMA450 for M2M and has embraced the technology as it pushes heavily into the machine-to-machine space.
Overall all these trends shall make wireless services a part of life, just like how we cannot imagine living without a cell phone in this connected world, so will these three trends influence the way of life in the next decade.
WiMAX on the very onset had a great time to market advantage for brining in an All-IP network along with TDD advantages that started the race for 4G supremacy. But somewhere along the line 3GPP caught up with the onset of LTE specs development and has commitments from more than 88 operators across the world and an ecosystem was born. The other day while watching TV, I had an analogy – Larry King had just announced his retirement from CNN and he was speaking with Bill Maher, and when asked of his successor, he mused maybe Ryan Seacrest. That is when it struck me WiMAX is like Bill Maher – a great guy but his place is on HBO not mainstream CNN, and Ryan Seacrest is like LTE, effervescent and very mainstream.
This reminds me of the other wireless battles in the past the CDMA vs. GSM, which complemented each other and help make the user experience better. The battle is never about which technology is better, as both have their own advantages and disadvantages, but about the adaptation by the suppliers and the media. Most technologies adaptations are based on various factors like spectrum policy, economic considerations, supplier ecosystem, media and target market segment.
Here are five factors that have had an impact on the WiMAX ecosystem.
Economic Downturn impact:
The impact of the market crash in 2009 has had far reaching implications to all industries especially the discretionary spending budgets of the Telco’s to upgrade their networks. Many of the far reaching network augments and technology upgrades for traditional Telco’s as well as wireless providers were dictated by the economic factors. 2009 was a disastrous a year as it seemed at the outset, starting as it did with the catastrophe and bailouts for the financial industry, real estate, and the auto industry. And this not surprisingly has impacted the growth of WiMAX putting pressure on Greenfield operators. Several suppliers reported that a bottom had been reached and expected an upturn in business – modest or otherwise – going forward.
One of the biggest trend that developed over the last couple of years was the level of consolidation at the infrastructure layer; with several large RAN players either having exited the space or merged with other players over the last year. Nortel was divvied up and assets scooped up by other infrastructure vendors, Navini became Cisco to be shut down completely later, Starent was also bought over by Cisco, Wichorus was taken over by Tellabs, etc. One of the strong transformations under way in the telecom sector is the way large telecom equipment players are becoming Managed Services players (such as Ericsson, ALU and NSN); with an increasing part of their revenues coming from services business versus hardware / equipment sales.
- Corporate moves to control spending did not stall shifts to greater use of communications.
- Flat and pre-pay plans gained increased market share during 2009. While this put downward pressure on ARPUs and margins, the industry was bolstered by the complimentary rise in 3G/HSPA+ broadband.
- Government initiatives for broadband infrastructure and service development have gone forward in the US, China and Brazil.
- Operators stressed applications and a unified web-enabled experience more than ever before. The usage model has experienced a dramatic shift, which is evident in the rising market shares of Apple iPhone, Samsung, RIM and other web-device competitors. Google Android has made significant inroads.
- Underserved markets including Russia, Malaysia, and the African continent saw robust growth. A few markets such as India continued to see delays in spectrum auctions and deployments due to economic outlook.
- As expected, several operators have nudged out their earlier forecasts for commercial availability of LTE service into late 2010 or early 2011. Some operators announced they would upgrade to HSPA and HSPA+.
LTE and its variant of TD-LTE:
There are two versions of LTE. FDD-LTE uses the FDD paired spectrum with two separated channels, one for the uplink and one for the downlink, which is the type of spectrum most mobile operators have. TD-LTE uses TDD unpaired spectrum channels that combine uplink and downlink, and split resources on the basis of real-time demand. Voice is inherently symmetric in the uplink and downlink so it is well suited for FDD spectrum allocations. Data traffic benefits from TDD spectrum, as it is typically asymmetric but the degree of uplink/downlink asymmetry is not fixed. The development of TD-LTE was initially pushed by China Mobile and regarded as a mainly Chinese standard, similarly to TD-SCDMA.
The appeal of TD-LTE has widened well beyond China. The recent announcement of Qualcomm to bid for TDD spectrum in India to support a TD-LTE deployment confirms–although it was not required to validate–the emergence of TD-LTE as global technology, likely to command a substantial market share.
The FDD LTE and TD-LTE versions of the 3GPP standard are very similar. As a result, devices can support both the FDD and TDD interfaces through a single chipset–i.e., without any additional cost. This is a hugely important new development: TD-LTE will benefit from the wide availability of FDD LTE devices that will be able to support TD-LTE as well. Unlike WiMAX, TD-LTE does not need to prove to have a substantial market share to convince vendors to develop devices. Vendors do not need to develop new devices, they simply need to add TD-LTE support to the existing ones.
There is a lot of TDD spectrum available, and in most cases it is cheaper and under-utilized. 3G licenses frequently have TDD allocations and upcoming 2.5 GHz auction in most cases contemplate TDD bands.
The increasing availability of base stations that can be cost-effectively upgraded will make it possible and relatively inexpensive for WiMAX operators to transition to TD‑LTE using the same spectrum allocation. The transition will still require substantial efforts and be justified only in some cases, but it will make it easier for WiMAX operators to have roaming deals and to have access to the same devices that LTE operators have.
WiMAX operators will also be barely affected by TD-LTE in the short term. WiMAX is years ahead in terms of technological maturity, devices and ecosystem. This gives them a strong advantage in comparison to TD-LTE operators: They know the technology already, they have a network, and they have customers. They also have the choice whether to switch to TD-LTE or not–and, more importantly, they have no pressure to do so before TD-LTE has reached the maturity they feel comfortable with or until the WiMAX 16m prospects become clearer. WiMAX is losing the battle, but winning the war. WiMAX operators are increasingly keen on requiring vendors to be able to support both a transition to WiMAX 16m and to TD-LTE as smooth as possible.
That is the rule of evolution – big fish eat small fish!
IEEE VS 3GPP:
LTE development has been driven by operators; this type of initiative is one of the key differences between LTE and its predecessors, which were primarily vendor-driven technologies. Several operators (Sprint Nextel, China Mobile, Vodafone, Orange, T-Mobile International, KPN Mobile, and NTT DoCoMo) formed a limited liability company called Next Generation Mobile Networks (NGMN) Ltd in September 2006. Subsequently, NGMN defined the high-level requirements for all next-generation broadband wireless networks – not just LTE. 3GPP works very closely with NGMN to define the scope of work and the charter for LTE and LTE-Advanced.
In addition, the LTE/SAE (Service Architecture Evolution) Trial Initiative (LSTI) was formed through the cooperation of vendors and operators to begin testing LTE early in the development process. NGMN defines the requirements and LSTI conducts testing to ensure conformance. The 2008 Mobile World Congress was seen as a turning point for LTE. This conference showcased the increased momentum in LTE development and support from both the device and infrastructure perspective. Vendors showcased advanced LTE devices and infrastructure while operators announced their LTE strategies or trial plans.
WiMAX is an offshoot of IEEE wireless standards including 802.11, 802.16, 802.20, and 802.22 starting out with the view that the complex task of designing wireless networks must be chunked down into discrete task groups and purpose designed standards. These tasks are given mandates to fulfill specific functions and then work to collaborate across lines of development. This has been necessary because IEEE is open to all, and thus must build a consensus among many participants from around the globe who may have different orientations. However, this approach led to islands of development and commercial momentum that are less organized and strategic than the well-situated UMTS/LTE industry approach. The WiMAX effort has been embryonic – although developing a competitive supply ecosystem, WiMAX has not yet had the scale to play the role of market assimilator similar to UMTS.
The WiMAX Forum might have jumped forward in their thinking to the situation the industry faces today: it still faces the catch-22 of building commercial momentum while needing huge amounts of capital to acquire spectrum and fund large-scale deployments to compete with the mobile industry. Proponents of 3GPP LTE point to the large volumes their industry will develop that are expected to lead to lower cost per unit and operation efficiencies.
Backward compatibility with 3GPP and Roaming:
The first challenge for WiMAX roaming is interoperability. WiMAX is deployed in specific markets and is concentrated in urban areas in the US. In order for users to access WiMAX services outside of their operator’s WiMAX network coverage area, devices must be interoperable across other WiMAX networks and between various vendors’ equipment. But the ecosystem is yet to be delivered, as Sprint just came out with the HTC EVO last month.
The second challenge for WiMAX roaming is that of multiple WiMAX air interface profiles. Operators do not necessarily have the same frequency bands available within their respective geographic regions. Depending on the country, carriers may use different radio bands for their WiMAX networks, such as 2.5 GHz or 3.5 GHz, and client devices may be equipped to use only one of these. The WiMAX industry is in need of devices that support multiple bands. This was a challenge for previous generations of technologies as well, and was addressed by the availability of dual band, tri band and quad band devices. The same is expected to happen within the WiMAX space to address frequency challenges.
Meanwhile LTE doesn’t face a situation like this as the critical factor in 4G success will spill over from 3.5G – having the hottest hand-held devices. Suppliers will dance to the tune of the largest operators with the most significant coverage.
HSPA+ is aimed at extending operators’ investment in 3G/HSPA networks and easing migration to LTE. HSPA+ with 2×2 MIMO, 64 Quadrature Amplitude Modulation (QAM) in the downlink, and 16 QAM in the uplink will increase data rates up to 42 MB in the downlink and 11.5 MB in the uplink. In addition, the one-tunnel architecture flattens the network by enabling a direct transport path for user data between the Radio Network Controller (RNC) and the GGSN. Control data will still use the SGSN. There is also an option to integrate the RNC directly into the eNodeB, thereby eliminating the need for separate hardware. These additional capabilities address the need for augmented bandwidth, reduced latency, and network elements with the same 5 MHz channel bandwidth used in UMTS networks. Consequently, operators can leverage existing 3G spectrum to deploy HSPA+. In addition, this architecture supports enhanced VoIP services. As a result of these enhancements, the need to upgrade to LTE is not as compelling. Operators feel that 42 MB will meet their data requirements for the next several years. The only drawback is that HSPA+ is still a CDMA-based technology and will lack the increased efficiency of OFDM (orthogonal frequency-division multiplexing).
Here is a HSPA+ Vs WiMAX study by Rich Brome from Phonescoop.com
A test was run on the T-Mobile HSPA+ network and the Sprint 4G (Clearwire) network, across six locations in Philadelphia, and an average user experience was calculated.
- Both were considerably faster than CDMA EVDO Rev. A
- HSPA 7.2 devices deliver surprisingly fast data on T-Mobile’s upgraded network
- T-Mobile’s HSPA+ is more than twice as fast as WiMAX
- Latency test – T-Mobile’s HSPA+ was, better with a difference was one-tenth of a second
- Sprint about their WiMAX network is that parts of their Philadelphia network are already at capacity, meaning the network is “full” with existing users and, essentially, maxed out.
Just as Sprint is still building its WiMAX network city-by-city, T-Mobile is still in the process of upgrading its network to HSPA+, also city-by-city. Once a city has been upgraded, T-Mobile’s HSPA+ coverage is the same as their existing 3G network coverage, since it’s the same network, just upgraded. T-Mobile’s upgraded HSPA+ network is worth a hard look.
** This comparison has its drawbacks, as Sprint network is loaded with 4G devices, whereas T-Mobile doesn’t have any HSPA+ capable phones. Also Sprint uses the Clearwire network as a direct tunnel, which impacts the latency of the network.
WiMAX is truly at a turning point today. It’s time to market advantage is being offset by the incredible dynamism of the LTE community and the scale that it has achieved in record time. Cost advantage is the last piece holding the machine together. Although wireless is a market rich in niches, the possible survival of a defeated standard could be very much defined by its cost. After the successive salves of operators’ announcements about their selection of LTE, the question of the survival of WiMAX is completely relevant. Many in the industry are now thinking that WiMAX may eventually disappear altogether, or else remain restricted to a small niche.
With the significant momentum that LTE is gaining, the battle could be well over if WiMAX can’t retain the cost advantage despite its lack of scale. WiMAX market dynamics could help overpass the scale limitation and help bail the standard out. WiMAX’s ability to compete in terms of cost may define its future and eventually ensure that WiMAX could still be an option for service operators in some emerging markets, for vertical applications and other niches.
You can now download this analysis here - 5_Reasons_WiMAX_be_a_Niche_Technology