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Filtering in 3 Domains: Why PrismStation is the Greatest Product Ever Brought to the WISP Industry.


Back in the early days, I was working with a customer to replace an older, slower 802.11b 2.4GHz mini-PCI radio with Ubiquiti’s latest SuperRange2 802.11g hi-power mini-PCI module.  Response to the SuperRange mini-PCI cards had been overwhelmingly positive, but this user was experiencing significantly worse performance post-upgrade.  At first I thought it was bad hardware and shipped another card, but the results did not change.  I then worked with him, trying to improve performance through several attempts at design modifications but also to no avail.

At that point, I bought a sample of the older 802.11b card at issue for myself, which was based on the Prism 2.5 chipset from Intersil.  And like the “Prism” name implies, I quickly saw that this older card although slower in max speed, had a radio design with a superior “selectivity” — the ability to filter out neighboring channels.

But, how could this be the case? The Super Range (Atheros 802.11a/b/g based) radios were the latest technology and I assumed it would outperform the older 802.11b technology in all areas. After taking apart the Intersil Prism radio, things became clearer.

The Intersil radio was based on a true “superheterodyne” receiver architecture where the carrier was down-converted to an Intermediate Frequency (IF) and filtered with a dedicated discrete filter. Meanwhile, the Atheros radio, was a completely integrated CMOS chipset without any off-chip IF filtering.


So what does this all mean? The ability to filter a radio signal largely depends on 2 things:

1. The fractional bandwidth:

Filtering out a 1MHz channel at 1GHz (.1% fractional bandwidth) is much harder than filtering out a 10MHz channel at 100MHz (10% fractional bandwidth)

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2. The filter effectiveness:

A dedicated specialized filter is typically far superior than a filter integrated into an IC.

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In the case of the Prism radio, it optimized both areas. By having a down-converted IF of 384MHz, it was able increase the filtering fractional bandwidth. And with a dedicated off-chip SAW (Surface Acoustic Wave) filter, it had a much more effective filter. In comparison, the Atheros radio was built for complete low-cost IC Integration and had neither. It might have performed well indoors, but in outdoor WISP applications, the Prism radio could survive in RF environments where the Atheros based radio had no chance.


Filtering in the Frequency Domain

This experience would plant the seed for what we ironically call our “Prism Technology” at Ubiquiti. We wanted a way to leverage the speeds of the latest WiFi chipset technology but also retain the great “selectivity” of the original Intersil Prism radios.

What we patented would be counterintuitive to most. We essentially put our own radio in front of the WiFi chipset radio. How does this exactly improve performance? The diagram below helps explains the concept

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Our Prism technology receives the unlicensed band spectrum (5GHz or 2.4GHz), down converts to an intermediate frequency, applies specialized hi-selectivity filtering on the area of interest, and up converts the channel back to appear magically “clean” to the WiFi Radio.

We have proven selectivity improvements of up to 30dB. To put this in a linear perspective, our Prism Technology reduces noise seen by the Wifi radio by up to 1,000 times!


Filtering in the Spatial Domain

Horn antenna technology has been around for over a century, but only recently have they been attractive and proven to be successful in WISP applications. In the early days of this industry, antenna gain was most valued and traditional sectors and reflectors were best suited for deployments. Fast-forward to today, with billions of unlicensed radios in use worldwide, the ability of antenna isolation to mitigate noise is becoming more valuable. We want our antennas to only hear and talk in a single direction and “ignore” all other directions. Horn antennas do this exceptionally well.

The challenge for our antenna team at Ubiquiti was how do we take advantage of the RF isolation advantages of horns, but still maintain enough antenna gain required for high performance links?

The answer is what we call “asymmetrical horns” and we believe they are the future of WISP deployments



Filtering in the Time Domain

The 802.11 WiFi standard uses something called CSMA/CA (Carrier Sense Multiple Access / Collision Avoidance). It is a contention based protocol which means if all clients on a network can “hear” each other, everything can work well. But, in the case of outdoor networks and isolated directional links, most of the clients cannot hear each other and end up talking over one another. To solve this we introduced a TDMA (Time Division Multiple Access) protocol where clients are assigned organized time windows to talk so they do not interfere with each other.

This was the essence of our AirMax TDMA protocol we have improved throughout the years. While this works well for clients connected to a single AP, what about interference issues with multiple APs co-located together?

Our all-new GPS synchronization protocol specifically addresses this challenge. PrismStation uses GPS to provide a global synchronization timer for potentially every deployment in the world. What this means is multiple BaseStations can work seamlessly on a single tower or neighboring towers and even using the same spectrum. And we can also achieve synchronization between AirMax and AirFiber Basestations (including our upcoming LTU technology)


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We believe the culmination of technologies driving 3-Domain Filtering (Frequency, Spatial, Time) will enable the next stage of high-performance, high-density AirMax networks throughout the world.  We are really proud to bring this product to market and hope it will be the weapon that operators can use to fight and build higher performance networks even in the presence of increasing amounts of RF noise in the unlicensed bands.

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UniFi — The Beginning of The Higher Market Disruption

How An Outdoor Wireless Company Entered the Enterprise WiFi Market


Perhaps now hard to believe, Ubiquiti’s decision to enter a new market with the introduction of UniFi in 2010 was generally criticized. At that time, some questioned why a company driving explosive growth in the outdoor Wireless Internet Service Provider Industry would risk diverting their focus. Others questioned how Ubiquiti, having less than 25 employees and none of them marketing or sales people, could possibly enter a market dominated by traditional sales models. Nevertheless, I saw an Industry ripe for disruption and a perfect opportunity for us to leverage our core strengths.

Exactly why was it so compelling? In 2009, if you took apart a $1,000+ “Enterprise WiFi” AP and compared it to a <$50 consumer WiFi AP, you would see 90% component/material overlap. Enterprise vendors were essentially over-engineering consumer WiFi reference designs for often little more than incremental performance benefit and then dramatically over-charging for them. Ubiquiti’s past success was attributed to a completely opposite philosophy — making designs more cost-efficient (while enhancing performance) and passing savings on to the customer. And our increasing economy of scale at this point (1mm+ AirMax radios/ yr) reinforced what I saw as an excellent Enterprise WiFi opportunity. I believed a solution at just a fraction of the cost combined with a basic features set and some “Ubiquiti magic” would find its way to disrupting the market and breaking the established IT sales dynamics.

What exactly do I mean by “Ubiquiti magic?” Well, market timing and cost-disruption alone do not make a disruptive product. If they did, then many vendors focused on low-cost hardware plays wouldn’t be struggling with marketshare and achieving profitability. There is a reason why Ubiquiti, a cost leader, is also by many metrics the most profitable hardware company in the world. Making disruptive products also requires a kind of design magic — something that conveys to the customer qualities of premium craftsmanship, thoughtful usability, and ingenuity which in turn spark intrigue and evangelism. In fact, many people think it was our user community that lifted our brand and products to success, but it very likely was the other way around.

Here are a few examples of “Ubiquiti magic” inherent in the UniFi platform launch in 2010:

1. The “UniFi” marketing brand

“Uni” — which means to combine multiple pieces into one; paired with “WiFi” creates “UniFi” — the perfect name for a system that manages multiple WiFi AP’s within a single control plane. Even better, this word transcends languages nicely — this is important as non-native English speakers makeup a big part of our customer base.


2. The industrial design

Inspired by the Airport Extreme project I worked on at Apple, but optimized for wall and ceiling installation. Lower-profile dimensions for a seamless mounted presentation and antenna patterns optimized to direct energy angled out. A glowing circular LED ring was used to give the product a “personality” that changed colors according to device state. (a design element that was quite original at the time)


3. The 3-Pack

Also a unique idea at the time was the AP 3-pack which framed the marketing message that UniFi was a scalable system. (Today we have evolved to 5-packs to support the higher installation count of typical UniFi deployments)


The Performance Story



To those who have followed UniFi’s history, it is no secret that we struggled post-launch to improve performance and quality of the platform. Following the initial success of the product, we urgently needed to improve across multiple areas including feature expansion, wireless performance, better quality control, and more attention to user experience. Disappointingly, we just failed to execute. So what exactly happened? Sometimes a development team that is good in taking a project from concept to market is not the team best suited to scale and perfect. Eventually we made the tough decision to pivot towards a complete restructuring of the platform development team and strategy. (Similar to our pivots in the Airmax world at around the same time).

As a result of these changes, we started executing far more effectively across all key performance areas of the platform as well as introducing new products and technologies at a rapid pace. While it may have looked like growth was slowing just a couple years ago, UniFi is now re-accelerating, growing faster than ever before and recently becoming the highest volume shipping Enterprise WiFi platform in the world. Even more exciting, we are on the brink of a second-wave of disruption, attacking the higher ends of the market and not because of cost, but because many believe UniFi is now simply the best all-around performing platform in the Industry and here is why:

1. Performance

A true enterprise WiFi AP today should be fast, resilient, and reliable. It should be near-ethernet speed under light load, provide solid performance and low-latency under heavy loads and interference, as well as maintain stability at all times — even when faced with possibly any of thousands of older quirky 802.11 legacy devices fighting for air time. The UniFi platform was always effective in delivering elegant AP management, but it wasn’t until last year that we achieved true enterprise wireless performance — and we haven’t stopped there. In fact, by many accounts, UniFi has now quickly ascended to be the top performing WiFi Solution in the Industry.


To get to this level of performance has been an exercise in persistently testing and optimizing of the wireless driver performance with rapid iteration. In fact, we have built teams to develop tools just to allow us to conduct testing more efficiently. These tools combined with the transparent feedback of our community, who have collectively deployed 10mm+ AP’s, has enabled us to make excellent progress in a short amount of time.

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2. User Experience

IT solutions are generally intimidating to operate and have configuration interfaces proprietary in nature. Traditional companies have used these as an advantage by creating training and certification classes which “lock in” system integrators after they have invested into the deep learning curve. We have taken a very different approach. While UniFi has tons of advanced functionality, we constantly strive to build a user experience that is visually intuitive and can very quickly be mastered by nearly anyone with a general networking background. Furthermore, the UniFi interface is designed to elegantly manage different technologies across different geographic locations all within a single framework.



3. Customer Service

It is widely known that Ubiquiti hosts a powerful community of system integrators who, together with our R&D, evangelize, improve, and support the UniFi platform. But UniFi also offers very responsive email support and real-time 24/7 online chat built into the controller, available free of charge.


4. WiFi Product Breadth

UniFi offers a comprehensive family of Access Points covering various applications including outdoor wifi, hospitality, education, and enterprises — each with unique form-factors designed specifically for their application use.


5. Feature Expansion

The UniFi team continues to expand the platform with new features including Integrated Radius server with insights for advanced installations, fully customizable hotspots with detailed analytics, as well as powerful deep-packet inspection reporting to characterize network use.


6. Technology Expansion

While UniFi is known as a WiFi system, it is rapidly expanding to adjacent technologies. The UniFi switching portfolio is quickly gaining market share and we are focused this year on bringing higher-end gateways, application servers, and other technologies to market — all managed within the UniFi controller.


 A Second Wave of Disruption


Interestingly, while UniFi’s performance has dramatically improved over the past couple years, we have been even more aggressive in our pricing strategy. For example, where our top selling 802.11n UAP Pro was priced at $229 MSRP, we introduced our UAP AC PRO (with several times higher performance) at $149 MSRP. We followed this up with very low entry points for our UAP AC Mesh and UAP AC Inwall each at $99 MSRP as well as with our hi-density POE Switching family also starting at $99 MSRP.

The obvious question — why would we sacrifice margins and profitability when we don’t have to? While it is true the above products would still be successful even at significantly higher pricing, we made a conscience decision to reduce short-term profits in an effort to maximize UniFi brand awareness, build greater long-term competitive advantage, and force the Industry’s attention to our marketshare gains. In turn, our hope was that UniFi’s performance could stand on its own and ultimately be recognized as a legitimate solution for higher-end markets.

And just as we hoped, UniFi (even without a sales force behind it) is now starting to make its way up-market into a more demanding customer base — one who values performance just as much as price. And in preparation of this next phase of evolution, we have been working towards a new product portfolio along with an advanced hosting and support solution . Specifically our “HD and “XG” series of products brings high density client support and 10Gigabit performance across WiFi AP’s, switches, and gateways. These new products are complimented by our UniFi Elite service launching this year that will offer a complete hosting solution, advanced RMA replacement, lifetime warranty, and expert-level phone support.



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The Evolution of Home Wi-Fi Part 2

Part 2: Welcome to “3-D Mesh” Home Wi-Fi

In Part 1, I talked about the inspiration behind the AmpliFi router design, but you may have noticed the AmpliFi Mesh Wi-Fi system also includes unique pieces of hardware called “MeshPoints.”

As proud as I am about the AmpliFi router, I believe the MeshPoint is the star of the platform. The design represents the ultimate example of form meeting function, powering complete ubiquitous Wi-Fi coverage in any home, including multi-story homes. In other words, MeshPoints were designed to expand coverage in the horizontal plane (one floor) and in the vertical plane (across multiple floors) — achieving three-dimensional or “3-D Mesh” home Wi-Fi coverage.

Let’s look at the key features powering this capability:

AmpliFI MeshPoint HD

The Integrated “Super Antenna”

The general rule of antenna performance follows something like this: the larger the surface area of the antenna, the more signal can be sent and received (which is why the antennas that send/receive signal into deep space are monstrously large). And this is precisely why traditional routers have “ugly” external antennas — they are able to extend range more effectively with these big antennas. This is also why larger devices such as laptops and PCs generally have better Wi-Fi range performance than smaller devices such as smartphones. The larger devices have more room for larger antennas.

For a mesh system, antenna performance (and antenna size) is critical. Why? Because intuitively, consumers will place mesh access points (“APs”) in areas where they currently do not have good Wi-Fi coverage. But if their existing Wi-Fi devices cannot connect back to their main router, how will a secondary mesh AP (with a similarly weak antenna) do any better?

Common Mesh Device Limitations

The recommended “compromise” by many manufacturers is to place the secondary mesh AP somewhere between the main router and the dead-spot area. This allows the mesh AP to have a strong link to the main router yet still extend the overall Wi-Fi network signal. But this leads to another problem — these “middle” areas tend to be in hallways instead of rooms. And who wants to have a box and AC power cable lying on a hallway floor?

Common Mesh Device in Hallway Requirement

The AmpliFi MeshPoint solves each of these problems by cleverly disguising a “super antenna” inside a very powerful hardware system, enabling it to achieve a much stronger link to the main router compared to common Wi-Fi devices. This allows users to practically install the MeshPoint directly inside the dead-zone area and solve Wi-Fi connectivity issues. Best of all, the MeshPoint can be plugged directly into any outlet without a clumsy AC power cable.

MeshPoint Placement Freedom

In addition, if the consumer wants to locate MeshPoints closer to the router to improve performance, this application is also cleverly covered by the same design. Because the MeshPoint has a very small footprint, it is able to sit flush against the wall in virtually any wall AC socket. And with the average home having 70 AC outlets, that represents a lot of placement freedom!

High-Performance 3×3 MIMO Integration

To say the MeshPoint antenna is “disguised” in a powerful hardware host cannot be understated. In fact, the MeshPoint packs dual 3×3 MIMO 802.11ac radios running at both 2.4 GHz and 5 GHz bands simultaneously along with a Bluetooth LE radio and an audio speaker. Having 3×3 MIMO Wi-Fi performance not only gives further range advantage, but a 50% maximum throughput boost as well. This greatly benefits mesh network performance and provides faster speeds when linking to high-end PCs and notebooks that also utilize 3×3 802.11ac technology — something not realizable with the general 2×2 MIMO Mesh Wi-Fi solutions (and unfortunately the majority of reviewers have not taken this advantage into account).

Exploded view of the MeshPoint HD Design

Ingenious Directivity Feature

The super antenna and 3×3 MIMO technology power the MeshPoint’s superior range performance. However, in order to fully realize the goal of “3-D Mesh” Wi-Fi coverage, we need a way to aggressively extend Wi-Fi coverage not just in the horizontal plane, but also in the vertical plane. Nearly all Wi-Fi solutions in the market today have antennas that send and receive signal in the horizontal plane only with very little signal extending in the vertical directions.


MeshPoint Directivity Range Advantage

The MeshPoint’s “super antenna” has omni energy coverage, but it also has a directive antenna beam that can be used for longer-range connectivity when aligned in a specific direction. The challenge we had was finding a method to give full rotational and tilt movement to this directional antenna beam while maintaining a compact product size and keeping the installed device relatively flush against a wall.

The solution we came up with is quite elegant — essentially dividing the product into 2 segments connected together by a magnetic joint. This key design feature allows the MeshPoint antenna directional freedom while plugged into an outlet and at the same time provides basic communications and power between the base and the main hardware unit.

MeshPoint Flexibility Enables True Ubiquitous Performance

Now, we have a way to aggressively pull signal from a multi-story home and even into a deep basement or a high attic. If needed, there are also “signal strength” indicators on the MeshPoints as well as audio speaker assistance to optimize installation and performance.

AmpliFi “3-D Mesh” in Action

AmpliFi HD 3-pack includes an AmpliFi router and 2x MeshPoints

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