In the coming months and in the immediate years that follow, wireless communications’ 5G small cell telecom marketplace will see explosive growth. The expansions not only will make the ultra-fast network reach the smart devices of more citizens; it also will include a massive infrastructure build out in an effort to maintain the high frequency bandwidth. Telecom providers will be placing antennas and repeaters on countless structures such as buildings, billboards and of course, light poles. There is always a growing concern from citizens who believe that 5G is a bad thing and it’s benevolent that tower owners and designers always think about how to camouflage their structures to avoid over-exaggerated public outcry. If a light pole structure does not exist, or if one needs to be erected to match existing structures, it’s imperative that reasonable concern be given to the aesthetics of the surrounding areas, structures and poles to be sure that a streamlined look prevails.
In considering the extreme infancy of small cell monopole concealment, one must applaud the companies that were so creative to make the pole look like a palm tree. Although it could be picked out of a desert landscape as the lone, odd-looking tree, with this effort, the concealment game had begun. Nowadays, those companies and the competitors who followed their lead have really taken entire pole concealment to a radical new level. Paint schemes, materials and selective placement have grown by leaps and bounds in the last two decades, making finding a new camo-tower within a group of real trees a legitimate task.
Being able to maintain a strong 5G signal requires cities, municipalities and private institutions to either convert or erect new small cell towers with state-of-the-art antennas, radios and other communications devices. In many cases, tower manufactures are able to match the look of an existing light pole so that the layman walking down the street, whom does not raise his neck to gaze upward, won’t recognize the difference between a streetlight of yesteryear or one that’s got a 5G node at its top. Part of maintaining the continuous look of the standard light pole in any location is that the focal point is not shifted away from the base, which is repeated as you walk down the sidewalk. Many of the bases that are found on commercial lamp posts are made from either metal or aluminum and painted to match the pole. Those bases are heavy, cumbersome and expensive. The paint chips off; the sun, snow, salt and climate degrade the materials. It often takes two people, and sometimes a small crane, to lift the large bases into place. In some cities, vagrants have taken to removing access doors or entire bases, and those stolen goods find their way to a scrap yard to be sold for pennies. This leaves many cities vulnerable to secondary problems such as continued vandalism, or worse, exposure to liability for electric shock, should a no-good begin to access the wiring.
As an alternative to some of the aforementioned scenarios, TerraCast produces a line of decorative, resin bases made to mimic the look of their metal counterparts, but with advantages that potentially outweigh (figuratively!) the competition. The growth of the TerraCast small cell concealment line of resin bases has been the collaboration and thoughts of many industry leaders who were looking for alternative solutions to high costs and long lead times often provided by today’s casting and metal manufacturers. TerraCast bases will not corrode, chip or need to be painted. They can withstand sun, salt, snow and other environmental factors, and because they are lightweight, a single person can reasonably be tasked with duties involved with manipulating and affixing the base to a structure.
Installing towers that either look like light poles or are light poles in historic districts brings its own set of unique challenges. Oftentimes, the amount of equipment hung on the top and perpendicular to the structure itself prohibits traditional decorative fluted poles from being candidates for deployment because they don’t meet the wind load requirements with all of the equipment. If the poles meet the requirements, they are nearly impossible to source at the diameter in which they need to be and have extended lead times, making them an unrealistic choice. TerraCast has created a patented solution for this problem by allowing any company to erect a round, non-tapered, structural pole in diameters of 8, 10 and 12 inches, and then cover them with TerraCast’s fluted sleeve, which will dramatically change the look and appearance of the round pole to become decorative and fluted. TerraCast supplied its decorative fluted sleeves to a flagship project in Pensacola, Florida, that fooled everyone into believing that the 10-inch-diameter poles were decoratively fluted. They were installed and customized, on the fly, in the field, to reveal all the necessary openings and attachments. (https://youtu.be/3pMidUVo52U) The sleeves not only added the needed aesthetics, but also provide a UV-stabilized, protective armor to the poles. The sleeve itself is made from a material that is color-through and never needs painting. These particular sleeves are black to match the project, but can also be ordered in any custom RAL color.
Concealment, of course, isn’t always just limited to line of sight. Oftentimes when radios and antennas are strapped to a small cell monopole somewhere below the top, the wires and connections exit the bottom of the radio unit and travel back into the pole via a hole drilled through the structure. Discerning municipalities believe that excess cable is unsightly and sometimes require contractors to hide those cables. Several aftermarket products can help to manage those cables, such as a traditional U-guard cable protector found at many major electrical component supply shops, yet others choose to have more robust custom parts made and have come to TerraCast in the past for help designing and implementing custom cable concealment boxes.
In the ever-changing world of telecom, 5G wireless communications technology has proven its worth and is here to stay. As residents begin to notice more communications-related infrastructure in their areas, constituents pray that designers, engineers, providers and city leaders understand the importance of concealment products that look good and remain maintenance-free for the lifetime of the project.
Brad Goldring is president of TerraCast Products. Visit www.terracastproducts.com.
Remember that “Stargate” episode when they wormholed past the sun and got flung back to 1967? No? You’re missing out; can’t beat MacGyver in space. Anyway, I had a similar experience (i.e., not really) happen when updating our outdoor small cell forecast (published next week). I read an article that I was certain was about eight years old — small cells were being trialed for deployment on street lamp posts. Nope, I was wrong; the article was current.
That problem — where to put outdoor small cells — is literally a decade old. Since then, many deployments have obviously happened over the increasing objections of many cities and municipalities. With good reason in some cases, since some pole-based small cell deployments gave squirrels’ nests a bad name. But they don’t have to, and many existing installations are unobtrusive particularly since some cities (like New York City) adopted a standard form factor for all deployments. Moreover, an entire niche industry of stealth towers and pole replacements emerged to help solve that problem while also providing room for additional equipment such as edge compute.
But municipalities restricted and delayed, and attempted to generate revenue from permits or pole attachment fees (and I’m oversimplifying) until the FCC acted to streamline the process. The result? Immediate pushback. Today, municipalities can basically only require carriers to adhere to aesthetic standards. Unless the town or city has deep pockets and is willing to fight, of course, in which case carriers usually just give up and move on — i.e., ignore the market (how many cellular carrier options are there, really?) or deploy more equipment on towers or rooftops, assuming they can find and lease space at a reasonable cost.
Then the pandemic hit, many office workers began working home and are now, it seems, staying there for two or three days per week. We expect that to continue. The result? Most of that previously urban, outdoor mobile voice and data demand moved to residential Wi-Fi and the suburban macrocell sites. One problem, of course, is that suburban towns are as protective of their aesthetics as big cities, so the problem of permitting and deploying outdoor small cells remains. Moreover, the timelines are as least as long as in big cities. Consider a town in Massachusetts where it took 20 months to deploy 40 outdoor small cells (i.e., two months per cell). An extreme example, perhaps, but one that begs the question: Why bother?
In the end, carriers are still trying to solve decades-old issues of placing the outdoor small cells. Everyone knows where they must go, but few (it seems) are willing to allow them that real estate.
Will there be new outdoor small cells deployed? Absolutely. The “new” mid-band spectrum used for mobile 5G NR services greatly benefits from being closer to end users while mmWave bands require proximity, if not line of sight. We were never sold on the use of mmWave in urban centers to address mobile capacity demands. (Fixed wireless is a different topic.)
From our perspective, then, iGR has not only lowered our pole-mounted outdoor small cell forecast, but also pushed it out by about 12 to 18 months. Stargate-MacGyver and his team had a choice: Live in the past or find a way home. What will today’s carriers choose?
Matt Vartabedian is iGR’s vice president of wireless and mobile communications research. Visit www.igr-inc.com.
Antennas are the wires of the wireless world. They are the last stop for a signal on its way from a transmitter and the point of entry for a signal coming home to a receiver. A wireless network can be built with the world’s latest high-performance radio technology and best fiber optic backbone, but the network will only perform as good as the antennas used to send and receive the signals from the radio. A poor quality, poor performing antenna will cripple overall performance and bring the high-performance radios to their knees. Without good antennas, wireless is just less.
But not all antennas are created equal. The right antenna can make the difference between a wireless system that delivers on expectations, and one that falls flat. When designing any wireless system, the antennas must be carefully chosen to fulfill system requirements and the demands of end users. Many additional factors must also be considered, from RF performance to installation requirements to site aesthetics to total cost of ownership.
In this report, we will examine a few different site antenna solutions, with a primary focus on small cell site antennas including cannister antennas and RF lens multi-beam antennas. Before we begin that discussion, we will examine the differences between macro cells and small cells and what those differences mean when selecting antennas.
Cell sites can be broadly categorized in two ways: macro cells, the conventional cells that encompass a relatively large area (on the order of miles); and small cells, a more recent approach to wireless coverage that encompasses a much tinier area (less than a mile). Small cells serve to make a given network denser, filling in the gaps between the larger macro cells to extend coverage or increase capacity. While all small cells accomplish this goal, there are many different categories of small cells depending on their specific function.
One common category of small cells is a distributed antenna system (DAS), which can refer more specifically to indoor and outdoor distributed antenna systems (iDAS and oDAS, respectively). These systems have become indispensable facets of our modern built environment. Distributed antenna systems are found in apartment buildings, offices, airports, train stations, stadiums, hotels, restaurants, and many more locations in order to add cellular capacity and ensure sufficient coverage for dense and populous hotspots. DAS solutions can be passive, active, analog, digital, or a hybrid of the three, and are designed specifically for a given space with known requirements.
Outside of iDAS and oDAS solutions, other categories of small cells complement macro cells more generally in order to densify a network. These types of small cells are often subdivided based on their size and target user, and common terms for these cells include microcell, metrocell, picocell, and femtocell, in descending order of area, power level, and number of users.
Small cells are becoming increasingly important as wireless frequencies increase—the millimeter wave (mmWave) frequencies deployed in 5G and even higher frequencies slated for future standards cannot propagate as far as the lower frequency signals common in today’s standards, though they can dramatically improve data throughput. To take advantage of such signals, it is therefore necessary to increase the number of cell sites, with each one of these small cells being closer in proximity to the end user than a conventional macro cell.
Distance between cell sites aside, small cells have several important differences from macro cells that impact the choice of antennas. For one thing, small cell sites are often in residential areas, which means they are constrained in both size and aesthetics. The large and looming macro cell towers on the outskirts of a town are not quite as appealing in the middle of a suburb. For this reason, small cell sites are often designed to be unobtrusive, in some cases even disguised. Some of the clever ways that wireless operators disguise small cells are by building them into fake trees, church towers or steeples, and even small decorative streetlight poles. The unsuspecting resident is none the wiser but enjoys the benefits of a robust and dense wireless network. If you have ever seen a fake palm tree with antennas sticking out of it, you have seen one of these small cell sites.
Power is another difference between macro and small cells. Macro cells aim to send signals far and wide for a mile or more, while small cells by design are much more limited in range—from about a mile at the largest to a few tens of feet at the smallest. Thus, the transmit power at each cell site can differ greatly. Even among small cells, the power level can range from 20 watts in an outdoor DAS to less than a tenth of a watt in the smallest femtocell.
For both macro and small cells, it is important to ensure the right amount of coverage for the cell. Too short a range and a cell may not be fully covered; too long a range and you may interfere with a neighbouring cell. It is therefore crucial to understand an antenna’s propagation characteristics and ensure it covers the correct area.
Antennas must always contend with trade-offs between size, directionality, gain, interference, frequency, and other system characteristics. For both macro and small cells, these trade-offs must be optimized to provide clean, comprehensive coverage.
For one thing, it is important to ensure that antenna beam patterns are directed properly towards the cell. The antennas must encompass the entire cell while not overreaching and interfering with neighbouring cells. Electrical or mechanical beam tilt can ensure that the cell coverage is properly bounded, and techniques such as beam steering can provide further control over the radiation pattern when necessary. To cover the full cell area, there must be multiple independent beams, and the beam patterns must be clean with minimal side lobes, high isolation between beams, and offer industry leading sector power ratio, which is a measurement of wasted energy found inside lobes compared to the main coverage beam.
Cell site antennas must also account for the different frequencies and wireless services that may be required in a given cell. Cell providers may own and operate their own cell towers and antennas, or they may share towers with other operators, resulting in several different sets of antennas operating in different parts of the spectrum, both licensed and unlicensed. Frequency bands can encompass wireless standards such as Citizens Broadband Radio Service (CBRS), Wi-Fi, 3G, 4G, and, increasingly, 5G. As wireless standards continue to evolve into 6G and further, cell site antenna coverage must keep up as well.
Another important factor to consider for site antennas is their structural integrity and installation requirements. Antennas high up on macro cell site towers may be exposed to strong winds and other damaging elements such as ice loading and constant vibration. Together with their radomes, antennas must be resistant to these environmental conditions while remaining light and accessible for installation and maintenance. Similarly, antennas should be concealed, when possible, especially in small cells and highly populated environments. The appearance of antennas should be customizable based on the surroundings or brand identity of the provider, who may wish to minimize visual impact or perhaps add a logo to their wireless infrastructure.
A popular type of antenna for small cell sites is called a canister antenna, named for its characteristic slim and cylindrical appearance. The singular name canister antenna is slightly misleading, as canister antennas actually package multiple antennas into a single container. In this way, canister antennas allow for sufficient wireless coverage and capacity while minimizing both visual appearance and installation requirements. Canister antennas are an ideal fit for small cell sites on light poles, power poles, roofs, and other existing urban infrastructure.
Since small cells are close together and often in noisy RF environments, it is important to ensure that canister antennas are not subject to high amounts of interference. To this end, always look for canister antennas with low passive intermodulation (PIM). Gammu Nu is a provider of site antenna solutions, including canister antennas, that are specifically designed to minimize both PIM and voltage standing wave ratio (VSWR) losses while maximizing gain and performance. Gammu Nu’s antennas are tested to provide PIM values less than 153 dBc and a VSWR below 1.3:1.
Gamma Nu’s canister antenna portfolio currently includes 14 distinct antennas across multiple frequency bands, with varying gain. The Pico or MESO canisters antennas can be customized per carrier for their specific frequency range/requirements.
The Pico antennas are as slim as (7.9 inches in diameter), small (as short as 23.6 inches in height), lightweight (starting at 12 pounds), and strong (with a rated survival wind speed of 150 miles per hour). The MESO canister antennas are 14 -16 inches in diameter, 0.6 meters – 4 meters in height, and strong (with a rated survival wind speed of 150 miles per hour). Some of the company’s canister antennas include RET (remote electrical tilting) device, allowing operators to remotely adjust down-tilt independently per sector.
Because canister antennas contain a full complement of radiating elements inside a slim and subtle housing, they are an easy and appealing solution for quick small cell deployments. They can provide 360-degree coverage for adding dedicated cell capacity to busy metropolitan locations such as airports, malls, plazas, and more. Small cell canister antennas can also provide an easy way to extend network coverage without requiring the cost and time needed to build a macro cell tower.
For larger cell cites demanding higher gain signals than those available from canister antennas, a type of technology called a radio frequency (RF) lens may be appropriate. Like a lens in a magnifying glass that bends optical light, an RF lens bends radio waves in such a way as to shape the desired antenna signal. A popular example is the so-called Luneburg lens, a sphere with variable dielectric properties specifically formulated to focus a planar wave to a single point—or, conversely, to collimate a point source into a directional wave front. Since the Luneburg lens is spherically symmetric, multiple antennas can be placed around the surface of such a lens to create multiple independent beams focused in different directions.
Antenna provider MatSing, the global leader in RF lens technology, provides multi-beam antennas for a variety of cell site applications. RF lenses can vary significantly in size, with the biggest lenses measuring as many as 5 meters across. Lenses of this size are not practical for the constrained spaces and low profiles of many small cells but are designed to provide exceptional multi-beam performance for high-capacity venues such as outdoor concerts, stadiums, arenas, and downtown urban cores. For a closer alternative to canister antennas, RF lens technology can be minimized to provide high performance and high-capacity multi-beam antennas in a smaller form factor.
RF lens multi-beam antennas such as those provided by MatSing offer several benefits for cell sites. The properties of the lenses allow for multiple independent beams with high isolation between them and low passive intermodulation (less than 153 dBc). As with canister antennas, RF multi-beam lens antennas enable coverage of multiple bands in one package. MatSing’s multi-beam antennas provide the world’s cleanest beam patterns and offer individual beam tilt adjustment, enabling wireless operators to focus the beam exactly where the coverage is needed. The antennas are light in weight and structurally strong, allowing for easy installation and operation in harsh conditions. However, unlike canister antennas, RF lens multi-beam antennas do not provide 360 degrees of coverage in a single package. MatSing’s multi-beam base station antennas, for example, provide 120 degrees per band across up to seven bands.
As 5G continues to gain prominence across the globe, the demand for small cells and the antennas that serve them will only increase. Not only is a smaller cell size better suited to the higher mmWave frequencies employed in 5G, but the comparatively easy rollout and lower cost of small cells compared to macro cells is becoming increasingly apparent. Small cells provide a convenient means of increasing cell capacity, filling gaps between macro cells, and expanding network coverage. To do so effectively, the proper antennas solutions must be deployed.
In this report, we have discussed several of the considerations for proper antenna solutions, from their performance characteristics to aesthetics. For small cells, canister antennas and RF lens multi-beam antennas are both high performing options that provide clean broadband coverage in a single unobtrusive package.
As wireless standards evolve from mmWave into even higher frequencies (the terahertz range is under serious consideration for 6G networks, for example), small cell antennas will be an even more important component of urban infrastructure and, without exaggeration, a crucial enabler of our everyday lives. Cell sites that anticipate this growing importance will be poised to succeed as wireless technology continues to progress.
Source: Gap Wireless
To obtain a PDF copy of the “Site Antenna Solutions Report,” click here.
H3C, an IT infrastructure product manufacturer with principal operations in Hangzhou, China, has selected Keysight Technologies for peripheral component interface express (PCIe) compliance validation and 5G small cell performance testing to capture opportunities in data compute and 5G markets, according to information from Keysight.
“H3C has served the Chinese data compute market with digital infrastructure products including servers, routers and switches for more than 30 years,” a statement from Keysight reads. “H3C is now expanding into 5G technology with small cell solutions. H3C selected Keysight’s comprehensive suite of 5G and high-speed digital test solutions to continuously verify compliance to the latest specifications defined by standard organizations and industry consortia such as PCI-SIG, 3GPP, O-RAN Alliance and IEEE.”
Digital transformation at the edge of the network requires efficient management of compute workloads, the statement reads. It said that the design complexity of high-speed serial data links in servers, routers and switches in data centers is increasing as data rates rise. The complexity creates a need for high-performance, software-driven PCIe transceiver test tools, according to Keysight. The company said that its Infinium UXR real-time oscilloscope, bit error ratio tester (BERT), precision waveform analyzers and optical transceiver test solutions enable H3C to verify PCIe transmitters and receivers used in data center and cloud computing platforms.
“H3C also uses Keysight’s user equipment (UE) emulation solution, UeSIM to validate the performance of a network infrastructure under real-world scenarios across the full protocol stack by emulating real network traffic over radio and O-RAN fronthaul interfaces,” the statement reads. ” UeSIM, part of Keysight’s open radio access network architect (KORA) portfolio, addresses emulation requirements from the edge of the radio access network (RAN) to the core of the network.”
Small cells for 5G are forecast to grow substantially over the next decade, growing to 45 million units by 2031, according to new research from IDTechEx,
The growth in these small cells will be due to the adoption rate of sub-6 GHz and millimeter wave (mmWave) globally as well as the growth in internet of things (IoT) for broadband and critical applications, 5G rollout for enterprises, urban and rural and remote purposes, and utilization rate of different types of small cells.
Small cells will help to bridge the gap allowing signals to travel indoors and to other areas without interruptions.
Small cells are divided into three types: femtocells, picocells and microcells. Because of their smaller size compared to base stations, they can be installed in areas where a larger station would be inaccessible. IDTechEx said small cells would play a key role in 5G to deploy an ultra-dense network to complement a macro network and boost capacity.
The full research can be found in IDTechEx’s 5G Small Cells 2021-2031: Technologies, Markets, Forecast report.