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Westell Technologies Introduces In-building Wireless Team

A company that provides network infrastructure solutions, Westell Technologies, has introduced its in-building wireless (IBW) team.

“With a combined experience of over 100 years, Westell’s IBW team is an organization of talented individuals with one goal in mind: meet and exceed our customer’s expectations while focusing on innovation at the edge of communication networks by offering a comprehensive set of products and solutions,” a company statement reads. “With millions of products successfully deployed worldwide, we are a trusted partner for transforming networks into high-quality, reliable systems.”

The team members are:

  • Bill Dow: Dow has 38 years of experience in the RF market sector and manages the northwest regional territory. Before Westell, Dow worked in the Service Delivery Division of Motorola Solutions and owned a Motorola dealership and authorized service center. Dow was executive director of USMSS, the national trade association of Motorola servicers, for five years.
  • Rick Rausch: Rausch is a telecom industry veteran of 25 years working as an RF and DAS engineer for wireless carriers and DAS integrators and in sales for DAS/public safety equipment OEMs and integration. He has an electrical engineering degree and two years of graduate studies in digital communications. Rausch provides training classes for first responders.
  • Gilbert Martinez: Martinez is the western region sales director. Before Westell, he spent nearly 16 years as a regional sales director for one of the largest wireless integrators in the country – helping customers solve complex wireless problems for safety, productivity, and innovation.
  • Chris Nolte: Nolte is a senior sales engineer based in Southern California. He has over 19 years of experience in the RF design, engineering, commissioning and optimization of DAS/public safety systems. Before Westell, Nolte worked for multiple integrators in Southern California. Before getting into the wireless arena, he was a member of the United States Air Force. He worked as a tactical aircraft mechanic on A-10 Warthogs and the RQ-4A Global Hawk during Operation Enduring Freedom.
  • Kevin Kurz: Kurz is a senior sales engineer based in Asheville, North Carolina. During his career, Kevin has been awarded Presidents Club, spoke at numerous industry trade conferences and served as the first Safer Buildings Coalition Advancement Committee chairman.
  • Mike Brownson: Brownson is an industry veteran with over 45 years in the wireless industry, including two-way radio, cellular, microwave and unlicensed broadband wireless. He has invested 20 years dedicated to distributed antenna systems for public safety and cellular enhancement. As Westell’s director of business development, Brownson leads the company’s efforts to innovate, promote, educate and inform on all aspects of in-building wireless solutions. He also works with the Electronics Technicians Association in their in-building wireless education and certification program. He holds numerous industry certifications and serves on the Standards Technical Committee for UL-2524.
  • Gabriel Guevara: Guevara has been working in the wireless telecom field for the past 25 years. He worked as an application engineer in the early days of cellular technology, deploying and commissioning multiple base station radios. He also has extensive experience in the RF field of commercial wireless repeaters F1-F1 & F1-F2 and channels translating repeaters for digital standards. In his role as vice president of channels and IBW sales, he leads the sales and strategy efforts for IBW public safety products and solutions.

Source: Westell Technologies

In-Building Wireless Report

From Gap Wireless

Wireless connectivity has never been as crucial to as many people as it is today. In a new world shaped by social distancing, wireless capabilities have transcended convenience and have become the primary fabric of human interaction.

As recently as 2016, ABI Research reported that more than 80 percent of mobile data traffic occurs inside buildings. Buildings, by their nature, provide a physical barrier to wireless communication. Dropped calls, poor signals and slow downloads all result when building materials like concrete walls and low-emission windows obstruct radio-frequency (RF) signals. In the worst-case scenario, parts of a building may become wireless dead zones. There is also the question of capacity — buildings may be home to many more users than can be supported by a given cell tower.

In-building wireless (IBW) solutions serve to address these concerns. IBW solutions can ensure that networks deliver on quality of service (QoS) agreements and that quality of experience (QoE) expectations are met by building occupants. These solutions range from minimal passive signal routing that ensure coverage to sophisticated digital distributed antenna systems that add additional cellular capacity. There is no one-size-fits-all IBW solution; the correct approach depends on the nature of the building and the scope of wireless services required.

The following information examines different available IBW solutions, the challenges that come with them and the emerging technologies that are changing the landscape of IBW.


Distributed Antenna Systems

One of the most common approaches to in-building wireless is the distributed antenna system, or DAS. In the context of buildings, this is sometimes referred to as indoor DAS or iDAS.

The principle behind a DAS is simple: by placing antennas strategically throughout a building — e.g., one in each room — cellular signals can be distributed where users need them. The signals can originate outside the building, in which case an external antenna receives and sends the signals to internal antennas, or the signals can come from an on-site base transceiver station (BTS) provided by a carrier.

In effect, a DAS can increase cellular capacity for a building and allow wireless signals to clearly reach end-user devices.

There are many considerations when planning a DAS. For instance, will it need to support multiple cellular carriers? What sources of interference will need to be mitigated? Will the system need to respond to changing user behavior? How will it be installed, and how much will it cost? Several types of DAS architectures address these differing needs.


Passive DAS

The simplest type of DAS is called a passive DAS. Such systems are best-suited for smaller buildings without complex or changing requirements. A passive DAS receives cellular signals from an external antenna and sends them through a low-loss coaxial cable to a bidirectional amplifier (BDA). From the BDA, the signal is sent over coaxial cables to multiband antennas throughout the building, being directed with passive components such as splitters and couplers.

Passive DAS systems can be an economical choice for IBW, but design complexity increases with the number of carriers that must be supported. Installing coaxial cables throughout the building can be difficult, and passive DAS systems are particularly susceptible to passive intermodulation (PIM) interference.


Active DAS

As cellular technology has evolved, a much more common approach to IBW is what’s called an active DAS. Such a system resembles a passive DAS, but, as its name suggests, an active DAS employs active RF components. Although this results in a more complex system with higher power consumption, it allows much more control over the signal distribution. An active DAS is configured with a head-end unit that receives multiple RF signals and distributes them to remote radio units throughout a building. These remote radio units rebroadcast the RF signal through either integrated or external antennas.

Active DAS systems use single-mode (SM) or multimode (MM) fiber-optic cables between the head-end unit and remote radio units, a transmission medium that is both easier to install and less lossy than the coaxial cables used in passive DAS systems. This enables longer fiber-optic cable lengths in an active DAS compared with coaxial cable lengths in a passive DAS. In an active DAS, the fiber-optic cables feed into the remote radio units, which serve as the RF source for the antennas and which can be placed close to them, regardless of the length of the fiber-optic cable. In a passive DAS, the antennas are necessarily separated from the RF source by the entire length of the coaxial cable. This allows an active DAS to encompass much greater distances within a building (or campus) than a passive DAS. The use of fiber-optic cables also means active DAS systems have less potential exposure to PIM, though care must still be taken to guard against PIM in the passive RF components before the head-end unit as well as around the antennas.

Active DAS systems have a higher cost than passive DAS systems, as they require more equipment and more space to implement. However, they provide more flexibility as well. The signals sent to each antenna can be tuned band-by-band to ensure optimal coverage across the spectrum. With active gain elements and low-loss fiber-optic cables, active DAS systems are also a better fit for larger buildings.


Hybrid DAS

There is an approach between active and passive DAS called, fittingly, hybrid DAS. A hybrid DAS employs active components, including head-end units and remote radio units, in the same way as an active DAS. However, the remote radio units distribute signals passively throughout a particular zone of coverage in the same fashion as a passive DAS, routing RF signals via splitters and similar components to several multiband antennas. This saves on capital expenditure, as fewer remote radio units and less fiber optic-cable are required than in an active DAS. However, each remote radio unit must provide power high enough to support its zone of coverage.


Digital DAS

A variant of active (or hybrid) DAS that uses digital instead of analog signals is called a digital DAS. The configuration of a digital DAS is similar to an active DAS, with RF signals being conditioned and routed through a head-end unit over fiber-optic cables to multiband remote radio units and antennas throughout the building. However, whereas an active DAS distributes analog optical signals over the fiber-optic cables, a digital DAS head-end unit converts the analog RF signals into digital optical signals.

These signals can be sent directly to a remote radio unit, but additionally flexibility can be achieved by sending them to components called expansion units. These convert the optical signals into electrical signals and route them as necessary to different remote radio units, which can be determined in software. Older digital DAS products used Ethernet cables between expansion units and remote radio units, but modern systems like the Sunwave Solutions CrossFire 2.0 DAS use a hybrid fiber/power cable all the way to the end node. Digital DAS systems support Common Public Radio Interface (CPRI) or other communication protocols.

One key advantage of a digital DAS is that signals can be addressed to specific remote radio units. This allows building operators to adjust coverage dynamically throughout their facility; for example, switching signals from one zone to another based on the time of day. Another advantage is that digital signals have a much better signal-to-noise ratio (SNR) than the modulated analog signals on the fiber-optic cables, making them more resilient to losses. For this reason, it may be possible to reuse existing fiber-optic cables in a building rather than installing dedicated cables. A hybrid fiber/power cable can bring power directly to a remote radio unit. For example, the Sunwave CrossFire N2RU nano power remote unit supports eight bands with a power output of 20 dBm per band. If even higher powers are needed, such as in tunnels, digital DAS systems can also use high-power remote radio units powered with a local supply. PIM is largely alleviated in a digital DAS, though sources of interference around the antennas still must be considered.


Distributed Small Cells

An emerging architecture for IBW is distributed small cells (DSC), often shortened to small cell. In contrast to a DAS, which contains a centralized source with a single backhaul connection to the operator network, a small cell system consists of a network of individual nodes that each must have a separate power supply and backhaul connection. Depending on their coverage and capacity, small cells can be further categorized as metrocells, nanocells, picocells and femtocells in descending order of power.

Small cells have both pros and cons. They can often be deployed quickly and with lower cost than a DAS, but they are much less flexible. Small cells typically only support a single carrier and only one or two bands, whereas a DAS can support multiple carriers and bands. Small cells may not be an adaptable solution if the needs of a building change. To accommodate the individual backhaul links, some small cells (generally femtocells) need reliable high-speed internet, though other cells (generally nano and picocells) employ a dedicated backhaul to the carrier.


Approaching IBW Design

As we mentioned earlier, there is no single correct approach to in-building wireless solutions; what’s best for one facility may be a poor fit for another. We’ll now take a closer look at some of the challenges and trade-offs that must be balanced in any IBW solution.



Ultimately, an IBW solution will succeed or fail based on the experiences of the end users. Thus, it is crucial to consider these end users when planning a system. For example, an office worker using a smartphone will have a much different user experience requirement than a first responder using a two-way radio. With an ever-growing number of wireless standards and multiple operators to consider, it is necessary to ensure support for as many current and future mobile technologies as possible. For example, 5G is steadily rolling out and will become ubiquitous within the next several years. Although users will expect support for this latest standard, an IBW solution must not neglect older but common standards such as LTE and 3G.

It’s also important to recognize that 5G will in time be supplanted by 6G, which will give way to 7G, and so on. It is therefore vital to plan ahead and ensure that future technologies can be supported without completely overhauling IBW equipment or architecture.


Total Cost of Ownership

The total cost of ownership, or TCO, is one of the most important variables to consider when planning an IBW solution. More expense does not necessarily mean better experience. If you have a small-to-medium-sized building that doesn’t need to support many operators and that won’t change much over time, a small cell system or passive DAS can provide a perfectly suitable solution for the lowest cost. On the other hand, if your facility is large or spread out and will need to adapt dynamically to changing user behavior, a more expensive digital DAS system may be warranted. For an accurate picture of the TCO, you must consider the cost of all equipment (head-end units, remote radio units, cooling equipment, cabling, etc.) as well as all installation and operating costs (electricity, fiber leases, IP backhaul, real estate and roof access, etc.). Systems such as the CrossFire 2.0 digital DAS platform reduce TCO with features including extremely low power consumption and hybrid fiber/power cabling to simplify installation



It is important to understand and mitigate all sources of interference that your IBW solution may experience. A common source of noise is PIM, which can arise in passive RF components. The prevalence of PIM decreases from a passive DAS (most susceptible) to an active DAS (less susceptible) to a digital DAS (least susceptible) but must always be considered in a design, so make sure you look for components with low PIM. Besides PIM, there may be RF interference originating from outside your building.

This is most common in dense urban areas with a lot of wireless traffic. To combat such problems, RF insulation may be necessary.


Choosing the Right Antennas

Although a DAS can distribute RF signals throughout a building, the last stop before the end device is the antennas. In active and digital DAS architectures, some remote radio units have integrated multiband antennas, but it can often be advantageous to use external antennas. In this way, specific antennas can be chosen based on the setting and application they serve, such as wireless carrier, public safety or both.

Where an omnidirectional antenna may be useful in some circumstances, a directional antenna may make more sense in others. Choosing the correct antenna and placing it properly is a flexible way to tune your IBW performance (and aesthetic).


Finding the Right Partner

In-building wireless solutions provide a way to ensure sufficient wireless coverage and capacity for a given building. However, there are a variety of IBW solutions and architectures, each with advantages and trade-offs. For a quick and inexpensive way to add capacity, distributed small cells are an increasingly popular approach. For a complex facility with many users of different needs, a sophisticated digital DAS may be the only tenable solution. When partnering with IBW system and component providers, communicate the specific needs of your building. Providers like Sunwave Solutions offer a wide portfolio of IBW technology to help you implement the right solution.

Source: Gap Wireless

eMagazine Covers Public Safety In-building Wireless Challenge

ImperativeThe In-building Wireless and Public Safety Imperative is an eMagazine recently published by SOLiD and Hutton that describes the need for in-building wireless public-safety networks and the steps necessary for their widespread deployment. The publication, which was created for public-safety professionals, building and property owners, and the in-building wireless integration industry, looks at in-building wireless through eyes of fire and police chiefs, association leaders, a journalist, and solution providers and integrators.

The Public Safety “Imperative” is also a call to arms for safer in-building environments for the public and the first responders, according to Mike Collado, SOLiD’s vice president, marketing.

“To meet the challenges of the imperative, the stakeholders must implement fire and building codes and standards for indoor public safety communications; develop and innovate a toolkit of robust wireless communication technology and networks; and identify business models to overcome the burdens of complying with an unfunded mandate,” Collado said in a blog post. “To be sure, the imperative is shared by the public safety, commercial wireless and venue owner ecosystems. It’s time we move the imperative forward.” eMagazine Download

LTE, Small Cells, In-Building Coverage Top 2014 Trends

By Morgan Kurk…

As 2014 rolls in, the continued implementation of LTE and the ongoing data boom mean that for most wireless operators, modernizing and enhancing the capacity of their networks with the most efficient architectures and equipment possible will be a major focus. Increasing network capacity intensifies the focus on metrocells and indoor coverage. With this in mind, let’s take a look at what will be the biggest and most important wireless infrastructure trends of the next 12 months.

Everything LTE

The newest focus in the wireless industry globally is LTE. GSMA Intelligence expects the number of LTE connections worldwide to pass one billion by 2017.  As the world’s population begins to access the Internet at the speeds available on LTE, there will be no turning back. Operators will be forced to quickly update and fortify their networks.  Operators must ensure that their network evolution is well architected and accurately implemented to provide the exceptional experience that is 4G LTE to their customers.

Prior generation systems such as GSM were designed in a voice-only era and have aged as much as 20 years. As such they are not very efficient when delivering data. Forward-looking operators who are not deploying LTE yet will use 2014 to update their network equipment and architecture, preparing their networks for the arrival of 4G. Central to this preparation will be shifting to a remote radio architecture that will put much of the radio function on the top of the tower. This design replaces traditional coaxial runs with hybrid fiber optic and power cable, which is used to connect the remote radio heads at the tower top to the baseband units that remain at ground level. Advanced multiband and multi-technology capable antennas will be connected to the radio heads, improving performance and increasing power efficiency while servicing 2G, 3G and 4G simultaneously.

Implementing such technologies to modernize the wireless network is a sound investment for improving operating expense in all of its forms, from energy efficiency to maintenance, while improving reliability and preparing for an LTE rollout.

Bigger focus on small cells

Wireless operators will continue to increase their focus on “small cells” in 2014. This term is defined as everything that is not the macro cell. We further break it down into the metro (or micro) and indoor layers of the network. These layers are designed to significantly increase capacity by moving closer to the mobile device, working in conjunction with rather than in competition to sector splitting on the macro layer. The indoor layer of small cells may include pico and femto radios, distributed antenna systems and low power remote radio heads, while the metro layer is made up of microcells and medium power remote radio heads. Operators will place more focus in 2014 on how to most efficiently deploy and integrate small cells in more buildings and urban centers where increased use is dramatically slowing the network. With the proliferation of data intensive devices like smartphones and tablets, focusing on how to offload traffic from the macro site will become increasingly important in 2014.

Inside becomes the new outside

The increased focus on indoor coverage may ultimately compel operators to trial a whole new approach to their network, which I call the “inside-out approach.” Historically, operators deployed wide area macro sites and eventually worked their way indoors on an ad-hoc basis, starting with the most heavily used areas such as airports and arenas. With the recognition that more than 70 percent of mobile sessions occur indoors, operators will take a fresh look at how best to architect their networks. The inside-out approach will likely start in the heavy traffic areas indoors, where the exception rather than the rule is being on the macro network. The first trials of using indoor sites to cover outdoor areas as part of an inside-out architecture could occur in a large city in 2014.

Morgan Kurk is senior vice president, Wireless, CommScope.

Multi-mode Metrocells to Aid AT&T in Densification

While the metrocells that AT&T is currently deploying support UMTS and HSPA+, the carrier plans to push forward with more advanced technology in the future. Later this year the carrier expects to deploy units that will also support Wi-Fi and LTE, but it has not released the name of the vendor yet.

Jim Parker, AT&T spokesman, told AGL Small Cell Link, “Metrocells are largely in their infancy. They support a single technology, a single frequency band and a single sector. It is extremely limited.”

AT&T requested a neutral host metrocell last summer from the OEMs through the Metrocell Forum, which created a requirements document and distributed it around the world. “We expect metrocells to evolve into a neutral hosting ability, but not for a few years,” Parker said.

The carrier is in the second year of its three-year Project Velocity IP, which will deploy 40,000 metrocells.

AT&T is deploying metrocells through three separate divisions, the Antenna Solutions Group, which targets large public venues, the Advanced Enterprise Mobility Solutions Group, which targets enterprises, and local RAN organizations, which are deploying them outdoors.

Expansion of the Addressable In-building Wireless Markets

AT&T is seeing significant growth in metrocell deployments in retail outlets, such as Best Buy and Walmart, because of the large number of customers, but also because they are retail outlets for the carrier’s phones. Metrocells can be economically deployed in places where a DAS network would be too expensive.

“The total number of addressable markets for wireless in-building systems has now significantly expanded with the advent of metrocells,” he said. “Now with metrocells at a much lower cost, we are able to go after markets that were previously unattainable, like multiple-dwelling units, retail and smaller hotel chains. We will even drop metrocells into the basement of a building that otherwise has good in-building coverage. In the past we would simply walk away from those opportunities.”

The carrier has negotiated master lease agreements with several nationwide chains of hotels and retail stores. Big box chain stores, with cinder block walls and metal roofs don’t always have the best macrocell penetration. An in-building metrocell helps facilitate the salesperson’s ability to activate the handset, according to Parker.

The decision to deploy metrocells versus DAS is also guided by capacity needs. Current metrocell technologies support up to 32 users. Compare that to a DAS. The DAS antenna can support multiple wireless operators, multiple wireless technologies, multiple frequency allocations, and the system can be expanded through sectorization.

Don’t expect to see a lot of metrocells in stadiums where capacity is king. Metrocells can be used where capacity needs are not as great, such as Marriott Courtyards.

“We are deploying metrocells in corporate America where the employees are encouraged to bring their own devices, but they don’t have adequate coverage,” Parker said.

Project Velocity IP, which includes macrocells, DAS and metrocells, had its first metrocells field application in the fourth quarter 2012, with wide-area deployments commencing the first quarter of last year. By 2015, metrocells will be the dominant technology of choice used in AT&T’s densification program, according to Parker.

“We are very much in the early stages of deployment and currently utilize specially trained personnel to deploy the metrocells, but due to their plug-and-play architecture, simple IP-connectivity and self-organizing architecture, we envision a day when we will be able to simply ship them to our enterprise customers and have their IT technicians deploy them,” Parker said.

The RF output of each metrocell varies from 39 milliwatts to 250 milliwatts, which is comparable to the power output of other indoor wireless solutions. The metrocell has a Fast Ethernet interface, which can use the building’s existing Internet access for backhaul and can be either shared or dedicated. The self-configuring architecture reduces the time and cost of installation.

Each metrocell can support 16 or 32 devices and can support simultaneous voice and high-speed data sessions. Each metrocell covers from 7,000 to 15,000 square feet depending on building layout and construction. Multiple metrocells can be deployed within a facility, allowing for seamless call handoff within the premises.

Each metrocell has a Fast Ethernet interface and can use the building’s existing Internet infrastructure, which offers less cost, simplified site acquisition and faster deployment. However, the quality and performance of the system is dependent upon the customer’s infrastructure, routers, switches and the cables that are maintained by the customer. The operator has restricted visibility into the network, making it more difficult to manage and maintain.

A metrocell can also be deployed with a dedicated network and backhaul, which provides additional network control for the operator, more network visibility and the ability to maintain the system end to end. The disadvantages of this approach are: more site acquisition requirements, running cable to each metrocell, increased capex and opex, and longer deployment time. More control over a network is always preferred by the carrier.

“We have been deploying our own LAN infrastructure to be able to manage and monitor end-to-end performance,” Parker said.

Metrocells Pass the Test

In the first field applications that took place in 2012, AT&T wanted to evaluate the performance of metrocells across a wide range of environments, including an outdoor residential area, an office campus and an urban high-rise in New York City.

For the outdoor environment, AT&T deployed 14 metrocells in the residential area of Crystal Lake Park, Mo., a small town located west of St. Louis. The system resolved spotty coverage caused by hilly topography. After deploying the metrocells, the macrocell performance improved with a 40 percent reduction in dropped calls.

To test the technology in the office campus environment, AT&T deployed 12 metrocells in an office building in Waukesha, Wis. “We realized a 15 percent increase in network traffic and a reduction in the call drop rates,” Parker said. “With ubiquitous wireless coverage throughout the facility, we have seen a significant increase in data traffic with more than 50,000 data sessions per day.”

AT&T deployed 20 metrocells for multiple enterprise customers in New York City. In order to reduce the amount of time to deploy the system, the carrier used the customers’ existing Internet wiring or a shared network to backhaul the metrocells.