- March 14, 2016
- AT&T, backhaul, California ISO, cost per mile, DWDM, E-Band, fiber, fiber optic technology, FierceWireless, IP/MPLS, Layer 3, RCR Wireless, Re/code, SDN, software defined networking, Sprint, urban backhaul, Verizon, Wireless Week
In late January and into February 2016, a big tumult ensued when Sprint announced that it would begin to move its mobile backhaul strategy from one based on leased fiber to another based on owned microwave radio. The story first ran in technology news site Re/code and quickly got reposted with additional commentary by FierceWireless, Wireless Week and others, and which was reiterated this week in RCR Wireless.
While the breathtaking headlines about reducing costs by $1 billion caught most people’s attention—primarily through reducing tower leasing costs and not using competitors’ networks—lower down in the copy came a potent reminder from Sprint about the economic benefits of microwave radio. It also highlighted the fact that backhaul has entered a transitional period (see article end for more on that).
Most of that $1 billion that Sprint seeks to save comes by way of moving away from AT&T and Verizon fiber backhaul networks. You might think that Sprint would build its own fiber network instead. But that would take too long and still have an exorbitant price tag associated with it. It’s a function of both out-of-pocket capital costs and embedded lost opportunity costs. Bottom line: laying fiber connections is expensive and slow. Putting up a network of high-speed, broadband microwave relay towers is quicker and easier.
- February 21, 2014
- 70GHz, 80GHz, backhaul, densification, E-Band, microwave communications, microwave congestion, millimeterwave, small cell, small cell backhaul, small cells, urban backhaul, urbanized backhaul
As the telecom community searches for reasons why Small Cell architectures have not yet launched en masse, “experts” are quick to suggest that lack of backhaul technology as the key perpetrator.
As I wrote in a 2013 article, starting with wireless microwave communications (6-42GHz frequency range), solutions for backhaul both large and small are available and effective today for mobile operators.
This is the second in a series that highlights technology available to enable immediate deployment of small cell backhaul. This segment focuses on the convenience of using wireless E-band as a complement to microwave for small cell backhaul, while bringing to light some of the true obstacles to small cell adoption.
E-band is a part of the electromagnetic frequency spectrum in the millimeter range between 71-76 GHz and 81-86 GHz. In recent years, there has been more interest in this frequency band, because traditional microwave (6-40 GHz) bands are now very congested in parts of the world, and that with the densification of mobile networks due to the introduction of 3G/HSPA and 4G/LTE, link distances between cell sites are shrinking in urban areas.
The surge in interest in a new network of outdoor small cells is driving a new approach toward cost-effective wireless solutions for backhaul. E-band offers a large swath of available spectrum with more than 10 GHz at stake—it represents more bandwidth than all the combined open frequency bands below 40 GHz.
What is needed is an all-outdoor, packet millimeterwave radio, offering a rich set of features, expressly built to support mobile (macro and small) backhaul by:
- Conforming to planning and local authority “community-friendly” aesthetics and design approval guidelines
- Eliminating external parabolic antennas, thus enabling significant savings on shipping, storage and handling costs
- Weighing dramatically less than competing solutions, resulting in easier handling and installation within 30 minutes
- Consuming less power, allowing flexibility in electrical source options such as via fixed supplies or Power over Ethernet (PoE), with built-in surge protection
As the world becomes increasingly urbanized—for the first time ever, more than 50 percent of the world’s population lives in dense urban areas—it is also the place where we communicate the most and networks are most stressed to keep up. Small cell designs offer a convenient method to densify networks.
However, my prediction is that in the near to medium term, deployments will be surgical—to plug gaps where coverage is poor and to fill hot-spots where incremental capacity is needed. It is important to note that outdoor, public access small cells will coexist and in some ways compete with other densification solutions, including DAS, wi-fi, and additional macro cell builds. Small cells may indeed need to be backhauled from light poles and building sides, but ultimately they need to go where they need to go, while serving the primary goal of not-spot and hot-spot filler.
The more pressing obstacles for outdoor small cells include the method operators use to assess the business case and solve the construction and site acquisition challenges borne by the paradigm shift. The expectation is that the ecosystem will produce a solution that makes small cells easier and cheaper to deploy than macro cells. The problem with that thinking is the economics of it all. The business case will continue to struggle to prove out vs. macro cell, as scalability and network dimensioning quickly come at odds with requirements for unbridled capacity, high reliability and network intelligence.
Operators think they may be vying for a diminutive device supporting multi-generational, multi-band, multi-media and multi-OSI-layers, but that utopian requirement breeds complex challenges in permitting, site acquisition, interference, costs, and so on—all items recently in the pick-list of a flash poll by Light Reading. I maintain that we are not just over-thinking, but over-expecting the benefits of a pure-play small cell rollout. We might all be better off following the “K-I-S-S” principle for the foreseeable future, which might produce this guidance:
- Use small cells only where it makes sense
- Deploy it with tried and true technology (i.e., wireless microwave)
- Consider E-band for expansion in dense urban outdoor environments
- Be mindful about keeping your budget in the black, but don’t stress about challenges that need not manifest in your business
So here’s to Keeping it Small and Simple!
Senior Manager of Marketing
For years and years, microwave and millimeterwave radio technologies have coexisted without very much overlap in either their markets or applications. Microwave radio served telephone company needs (e.g., long distance backhaul, mobile access aggregation) for the bulk of its implementations with some vertical deployments for oil and gas, public safety and utilities organizations. Typically, licensed bands in service ranged from 6GHz to 42GHz—with 11GHz and under popular for long haul; 18-38GHz trendy for short urban hops. Generally, millimeterwave radio is considered to be between the 60GHz and 80GHz bands and found its applications confined to those for intra-campus communication from building to building for universities, civic centers, other government conglomerations and large, spread-out (i.e., 1 to 5 miles) corporate facilities.
More recently, E-band has seen its profile rise, as mobile operators have had to “densify” their networks to service the more tightly packed populations moving into larger and larger cities around the world. This is due to at least two factors: the shorter distances between wireless sites in urban locations and the lack of available spectrum in the traditional microwave bands. E-band radios are now starting to be deployed to aggregate traffic from macro cell base stations in the Gotham-esque landscapes of the 21st century and the new small cell transceivers that venture where no full-size mobile base station can tread.
So into this brave new world of urban backhaul, next-wave E-band radios have been thrust. But small form-factors and spectrum availability are not going to be enough to ensure the success of this new generation of millimeterwave equipment. Additional features will be necessary. They will need capabilities such as:
- Integrated antennas to enable quick installation, minimize visual impact on city dwellers and overall promote “community friendly” backhaul
- Light weight for lessened load factors on light poles, street signs and other non-traditional metro wireless infrastructure
- Wide channels up to 250MHz in size
- Scalable capacity starting at 350 Mbps to 1 Gbps with room to grow
It is an exciting time in the E-band space in early 2014. We will share more as the year progresses. Check back regularly to stay apprised of developments.