Setting a Value on the US 2.3 GHz WCS Band

WCS Spectrum ValuationWhen the WCS band was first auctioned off in 1997, 30 MHz of spectrum in 2.3 GHz was sold for $14.8 million. At the time, it seems reasonable to pay that much for spectrum with stringent regulatory requirements on RF out of band emissions to protect the adjacent satellite DARS band (Digital Audio Radio Service). Now, the picture is completely different: AT&T acquisition of Nextwave’s WCS and some AWS assets for $650 sets a new price for the WCS band. It also clearly demonstrates how in spectrum limited market with high demand for mobile broadband services, the price for higher frequencies can increase significantly. So what would the price of the WCS band be and are there any lessons to draw from it? Continue reading

It’s the Signaling Stupid!

Wireless Network Signaling ProblemIf you have been following the wireless industry, you for sure would have heard of the capacity crunch and exploding demand for mobile traffic data services. Hardly any presentation by a vendor, analyst, and even operator starts without a graph of future traffic trends. But quietly, another problem has been brewing; one that has received little media attention, but which operators, vendors and industry insiders have recognized as a real and serious issue that warrants much work to contain: it’s the problem of exploding signaling traffic on mobile networks. To illustrate the challenge, Telus reports that  in Canada while the data traffic has seen tremendous growth of over 100% year-over-year for the past three years, the signaling traffic has grown by a staggering 2700%. Deutsche Telekom reported 360% increase in signaling traffic over a two year period spanning 2010 and 2011 even with the introduction of techniques that reduce the signaling load. Continue reading

Aligning Mobile Services with Spectrum Properties: Information Showers

Information Shower - Millimeter Wave CommunicationsOne essence of wireless communication does not change: the reliance on spectrum availability. The frequency spectrum is endowed with different features and characteristics that make trade-offs a necessity. One trade-off is that between data rate and mobility. The lower part of the frequency spectrum which is most amenable for mobile services due to economic reasons aggregate in a few gigahertz below the 6 GHz band. By comparison, the entire 60 GHz band features up to 9 GHz of spectrum where atmospheric absorption limits the range of propagation to short distances. As bandwidth correlate with throughput, we achieve much higher data rates at the higher frequency bands which are unfortunately less amenable to mobility services. So, how to bridge this divide? Continue reading

New Frontiers in Wireless Communications: Extremely High Frequency Communications.

WiFi 802.11ddThe success of personal wireless communications may have been inevitable: communications is an essential tenant of human social structure. Coupled with the proliferation of wireless communication has been a drive to open up new bands of frequency spectrum. The most recent example is the millimeter wave band around 60 GHz which was assigned for unlicensed use and is now part of 802.11ad standard activities. In other words, WiFi operation in 60 GHz is work in progress! But looking further ahead, what new bands can be made available? Continue reading

Twisted Waves: A New Dimension in Wireless Communication – Part 2.

Photon Orbital Angular MomentumPhoton Orbital Angular Momentum (OAM) is a new technique to increase wireless channel capacity. However, not everyone agrees that this is a conceptually new area in radio communication and they make the case that OAM is a special mode of MIMO communications. This view was presented in a recent IEEE Transactions on Antennas & Propagation paper.

The argument made is that OAM is a unique mode of MIMO theory which is obtained under certain conditions and therefore not a conceptually new area. These conditions are obtained when a circular antenna array configuration is used in free space communication which results in MIMO eigen-modes that are similar to the OAM states.  In this case, the argument is that OAM is a sub-class of traditional MIMO communication. Continue reading

Twisted Waves: A New Dimension in Wireless Communication – Part 1.

In some of my recent postings, I wrote about the limits of the physical layer and what that means for the future of wireless communications systems. Here, I like to mention new research that has promise of increasing the capacity of the physical layer. This new work is based on exploiting a property of electromagnetic waves heavily investigated in the optical range of the electromagnetic spectrum but yet little explored in the radio frequency range. Continue reading

Reaching The Limits of The Physical Layer: The Slow Shift To Enhancing Efficiency.

There is a general view that we are rapidly approaching the capacity limits of the physical layer. But as demand for capacity continues to grow, the supply of capacity is tapering off. What to do about this and how to continue to inject capacity is being addressed at standardization meetings. Let’s take a quick look at some of these techniques and some of their challenges: Continue reading

Cloud RAN vs. Small Cells: Trading Processing for Transport Cost.

Perhaps you heard of Cloud-based RAN (C-RAN), the latest acronym in the mobile industry. If you are familiar with “base station hotel,” then you’re familiar with this mobile network architecture.

C-RAN takes the distributed base station architecture to its extreme: It pools the baseband processors in a central location and distributes remote radio headends which are connected through dark fiber to the baseband engines. The distance can be as long as 40 km. Continue reading

MWC 2012: Larger Devices, Smaller Cells!

MWC 2012 Larger Devices Smaller Cells

Just back home from MWC’12… What a show this year… Over 67,000 attendees and some 1500 exhibitors, and some student protests in the mix… It was the biggest to date and a good finale for the Fira before moving next year to a new nearby location.

For those in the mobile infrastructure space, long gone are the days when infrastructure set the agenda. The show is now strongly dominated by the handset and applications of mobile technology to everyday life: in the home, the car, applications for entertainment and for health and everything else conceivable. Surely, the show is no longer bound for the industry’s elite, but is becoming a major consumer event. The crowds jamming the Samsung booth for a peak at the latest tablets and the buzz and excitement of the App Planet are but a couple of examples. Continue reading

TD-LTE and the Hype Cycle: Where’s the Business Opportunity?

As a new wave of hype is building around TD-LTE, I wonder what the fuss is all about. For certain, TD-LTE is not a groundbreaking technology – it comes many years after WiMAX and quite a few after its older FD-LTE sibling. But what intrigues me most is the business model for TD-LTE and especially the dilemma of the TDD spectrum holder: what is a winning business model that maximizes the value of my operation and company? Without such a model, TD-LTE will be yet another technology toddler that never makes it to adulthood. Continue reading