RESEARCH TOPICS
All
Research
Broadband
Energy
Wireless
Components
PARTNERS
Adkit
The
Infoshop
Mindbranch
MarketResearch.com
Research
& Markets
INFO REQUEST
CONTACT
NEWS
The Competitive Question of TD-CDMA
One of the technologies that will offer a viable alternative
when looking at WiMAX is TD-CDMA, also known as UMTS
TDD, which has not been given the attention we think it deserves when
discussing the assemblage of our broadband wireless world.
History
Originally conceived to occupy the 3G TDD (time division duplexing) bands as a data complement to
the widely deployed FDD (frequency division duplexing) variant of WCDMA, it has
since taken on a life of its own thanks to the efforts of IP Wireless, who
offers both a standard version employing a 3GPP compliant core network and a
more popular IP Wireless specific all IP version of UMTS TDD. All use WCDMA as
the air interface but IP Wireless’s version is data optimized and has feature
sets not yet included within the 3G specification such
as an all IP core network.
Advantages of TDD
TDD operation, which is also included under 802.16, enables
up and downstream traffic to operate in a single channel. That provides some
potential capacity improvement when bursty or asymmetrical traffic is the norm
and, perhaps more importantly, it facilitates spectrum planning by eliminating
the need for paired spectrum; only one radio channel is required for
deployment. Some radio cost reductions are also evident thanks to the
elimination of costly filters.
Looking at these possible advantages, to date UMTS TDD has been tested by major mobile carriers such as Orange and Nextel and it is deployed, mainly for fixed DSL replacement, in Portugal, UK, US, South Africa, Malaysia, Czech Republic, New Zealand and in others nations.
Expansion in the coverage of existing fixed networks has lead to portable use of the technology and addition of mobility management attributes is considered forthcoming (these networks originally served fixed applications so cell to cell hand-offs were not an initial concern and mobility functions were not initially activated in most cases).
Success has fueled substantial economies of scale (for the fixed wireless industry) and IP Wireless can employ certain off-the-shelf, typically, RF chipsets, which further facilitate production of low cost product. Basic UMTS TDD subscriber modems can already be purchased for under $200 in volumes. These typically employ IP Wireless’ own baseband chip and second part analog/RF chips.
Still a Mobile Contender
IP Wireless remains in consideration for major mobile
contracts in the short to mid term from carriers in Japan and the US. Additional
nationwide contracts from mobile operators in Europe
also remain open and the system is in fact in use in Czech Republic, Germany
and Portugal,
offering portability in the latter cases and moving to full mobile coverage in
the former.
However, Although, IP Wireless has been able to secure distribution agreements with major infrastructure integrators such as Alcatel, none of the leading WCDMA vendors are offering their own UMTS TDD product as of today.
Mobile TV
More Recently, IP Wireless launched a product it calls TDtv.
This is effectively a stripped down version of UMTS TDD which supports mobile
television and other streaming content in existing 3G TDD spectrum. The company
claims substantial interest in said product line since it enables carriers to
offer TV with existing spectrum and via UMTS technology. Deployment in the
system alleviates the contradiction in offering a non UMTS family product (such
as DVB-H) to fulfill the initial UMTS vision, a sensitive point amongst 3G
operators and investors. It also eliminates additional cost required for mobile
video specific spectrum.
Expectations
We believe UMTS TDD will occupy a mid-sized niche both in
the mobile and fixed worlds due to its existing momentum, performance and
mainly due to the existence of spectrum which is specifically intended for TDD
technologies such as UMTS TDD. Use of the platform specifically for mobile TV
is also likely, especially in Western Europe.
Is UMTS TDD a WiMAX killer? No it is not. For starters, most wireless spectrum which is suitable for mobile services is allocated for FDD not TDD. Secondly, while IP Wireless and other UMTS proponents will pursue UMTS's Long Term Evolution straight to OFDMA, some carriers want OFDMA before 2009, which is when LTE may become available. Lastly, leading fixed wireless vendors such as Alvarion and Airspan seek to have their respective existing fixed wireless customer base, much of which is concentrated in emerging markets, migrate to WiMAX. Most of these networks operate at 3.5 GHz and they allocated for FDD not TDD.
We expect UMTS TDD and WiMAX to coexist and we predict roughly equal sized markets for the two in terms of dollars in 2010.
© 2008, Visant Strategies