Sprint's Trebl: Magic Box + Alexa + HiFi Speakers

Sprint's award winning MagicBox that we have written about multiple times in this blog has launched a new product called Trebl that contains indoor Magic Box small cell, integrated Amazon Alexa voice capabilities and Harman Kardon sound quality.

According to Electronics 360:

The TREBL with Magic Box, introduced this week at CES 2019, won a CES Innovation Award in the Smart Home product category. TREBL is a wireless small cell that accelerates LTE data coverage and speed while controlling smart home devices using Amazon Alexa. The small cell can also play music with Harman Kardon audio through two 8 W speakers, an embedded amplifier, three built-in far-field microphones, Bluetooth, and noise and echo cancellation.

The TREBL with Magic Box is water-resistant, making it suitable for both indoor and outdoor use, and it is lightweight for portability.

And it has been nominated for MWC 2019 Glomo award too

Proud that @Sprint & @HarmanKardon’s latest innovation the #SprintTREBL is nominated for its 2nd award this year. It’s already a #CES honoree & now for #GSMA #GLOMOAwards! #MWC19 pic.twitter.com/l6zlPb3KWt

— John Saw (@SprintCTO) January 29, 2019

While we love the style, we are not exactly sure why someone would need this combination of Magic Box and Alexa. We will wait and see if it succeeds. In the meantime we wish Sprint the best of luck for Glomo awards.

Sprint's Outdoor Small Cells - In Pictures

Sprint has been deploying outdoor small cell with more than 15,000 already deployed. This is not as aggressive as T-Mobile that plans to deploy 25,000 just this year but Sprint is also deploying MagicBox, its indoor small cells. According to Sprint newsroom, more than 260,000 magic boxes have been distributed to date. In fact they are so popular that the hospitality edition was released last month.

In this post, I am going to post some tweets with pictures of Sprint's outdoor small cells:

New Small Cells going into Northglenn CO! #Sprint pic.twitter.com/rMHDoUWLaC

— eamon oleary (@OlearyEamon) March 26, 2018

They make it look easy! Turning up Small Cells in Clark Co NV! #Sprint pic.twitter.com/W7PuEMElTm

— eamon oleary (@OlearyEamon) March 29, 2018

.@Sprint has equipped @YankeeStadium with 12 mini macros and 2 six beam antennas to bring #Yankee fans and foes 2.5GHz! #NYC pic.twitter.com/u5c1f6GLEK

— John Saw (@SprintCTO) August 6, 2018

Our first small cell in Honolulu! First of many to bring our top download speeds to downtown Honolulu! #Sprint pic.twitter.com/gw5eHg81U0

— eamon oleary (@OlearyEamon) June 28, 2018

Adding Small Cells in Riverbank CA pic.twitter.com/iUa8OhjhPD

— eamon oleary (@OlearyEamon) March 15, 2018

Surrounded by trees and getting low RF at my house– Bolted one of these small cells on, plugged it in, and presto- I’m getting 60M downloads on #SprintLTE; 15x what I can get on #Centurylink DSL!! pic.twitter.com/QtOlUUhUPS

— eamon oleary (@OlearyEamon) November 18, 2017

Firing up those Small Cells in LA; A Thing of Beauty! @guengott68 #Sprint pic.twitter.com/gjtAWyYicr

— eamon oleary (@OlearyEamon) October 27, 2017

Turning up Small Cells in Phoenix #Sprint @guengott68 pic.twitter.com/bwZdMyjWok

— eamon oleary (@OlearyEamon) October 26, 2017

Deployed to improve customers’ coverage, reliability and speeds, #SmallCells are a crucial part of the @Sprint Next-Gen Network build! https://t.co/205BeNojNQ pic.twitter.com/iaCyM8Pdia

— John Saw (@SprintCTO) August 2, 2018

It should be pointed out that in USA, the definition of Small Cells is often fuzzy. While we refer to small cells as complete base stations, out there small cells can also mean small form factor RRH/RRU. Some of these small cells will have BBU hidden away. For more details see our tutorial on small cells and macrocells here.

Sprint's Small Cells in the stadium

Sprint's CTO John Saw posted a few pics of small cells in the stadium. They also posted a few pics about outdoor small cells (see below).

Another tweet from John Saw was about SpeedTests within the stadium.

The question often asked is why are the upload speeds so poor. I answered this question when I talked about High Power UEs (HPUE) in an earlier post. As they use TDD Config 2, they are focusing on downloads rather than uploads. This may be a bit strange scenario for stadiums where people want to upload rather than download but because they want to use HPUE, they have to make sure that only a limited number of uplink slots (less than 50%) are used.

TDD also mandates very tight synchronization requirements thereby making most networks keep the same config throughout their network to avoid interference.

Its nevertheless interesting, would be good to see how the end users react to this approach.

Further reading:

• Sprint's Network Gears Up for the Big Game!
• High Power / Performance User Equipment (#HPUE)

Relays (RN) and Donor eNode Bs (DeNB)

Relays a.k.a. Relay Node (RN) in standards has been a part of the standards for a while but I don't hear about them often. The only time recently when I heard about them were with Airspan's MagicBox small cells deployed in Sprint (see news here). In fact the article speculates:

LTE UE Relay was specified within 3GPP’s Release 10. There are different types of Relay and it would seem Sprint’s will be Type 2, which sees the Relay Node (or MagicBox) retransmit on the same code as provided by its macro “donor” cell.

While I don't have any further details about it, I am not too sure about it. Type 2 relays are complex and require change in the existing eNodeB's. I should clarify here that we are talking about Layer 3 relays in this post. An earlier presentation from Airspan mentioned that they use Type 1a/1b relay architecture. See here.

The presentation below has some nice simple explanation of the Relay nodes and its workings

In case of Type 2 relays, there is a much more architecture change involved. This architecture change requires modification of the existing eNB to Donor eNB (DeNB).

Going back to 3GPP TS 36.300: E-UTRA and E-UTRAN Overall description; Stage 2 document:

The DeNB hosts the following functions in addition to the eNB functions:
- S1/X2 proxy functionality for supporting RNs;
- S11 termination and S-GW/P-GW functionality for supporting RNs.

Further on, in section 4.7

E-UTRAN supports relaying by having a Relay Node (RN) wirelessly connect to an eNB serving the RN, called Donor eNB (DeNB), via a modified version of the E-UTRA radio interface, the modified version being called the Un interface.

The RN supports the eNB functionality meaning it terminates the radio protocols of the E-UTRA radio interface, and the S1 and X2 interfaces. From a specification point of view, functionality defined for eNBs, e.g. RNL and TNL, also applies to RNs unless explicitly specified. RNs do not support NNSF.

In addition to the eNB functionality, the RN also supports a subset of the UE functionality, e.g. physical layer, layer-2, RRC, and NAS functionality, in order to wirelessly connect to the DeNB.

The RN terminates the S1, X2 and Un interfaces. The DeNB provides S1 and X2 proxy functionality between the RN and other network nodes (other eNBs, MMEs and S GWs). The S1 and X2 proxy functionality includes passing UE-dedicated S1 and X2 signalling messages as well as GTP data packets between the S1 and X2 interfaces associated with the RN and the S1 and X2 interfaces associated with other network nodes. Due to the proxy functionality, the DeNB appears as an MME (for S1-MME), an eNB (for X2) and an S-GW (for S1-U) to the RN. 

In phase II of RN operation, the DeNB also embeds and provides the S-GW/P-GW-like functions needed for the RN operation. This includes creating a session for the RN and managing EPS bearers for the RN, as well as terminating the S11 interface towards the MME serving the RN.

The RN and DeNB also perform mapping of signalling and data packets onto EPS bearers that are setup for the RN. The mapping is based on existing QoS mechanisms defined for the UE and the P-GW.

In phase II of RN operation, the P-GW functions in the DeNB allocate an IP address for the RN for the O&M which may be different than the S1 IP address of the DeNB.

Based on the complexity and additional changes required for Type 2 relays, I am not surprised that they are not very popular. If you think otherwise, do let me know.

Thanks to Dr. Kit Kilgour for providing insights into this topic.

Drones, More Drones & Droneway

I have written about Drones and Balloons in the past, mainly to BT/EE. Take for instance this presentation by Mansoor Hanif at TIP Summit and this one on Flying Small Cells. In addition I have also talked about Telefonica's Nano cell, which is a small cell on a drone; Verizon's 'flying cell-site' and AT&T's flying COW.

This week the US operator Sprint announced that they are trialing their Magic boxes on drones. Here is a video on that:

Back in August, IEEE Spectrum ran an article on how Flying Cell Towers Could Aid Search and Rescue. Base stations carried by drones would form an ad hoc network and connect first responders.

Picture Source: IEEE Spectrum

From the IEEE Spectrum article:

An aerial communications system supported by drones could be deployed much faster and operate with minimal interference. In 2013, we started to think about what such a drone-based communications system for public safety agencies might look like. We knew it would need a shared radio-frequency channel for first responders, drone-portable base stations, a power supply, and a digital database for exchanging information. We would also need controllers that would be easy enough for a licensed drone pilot to operate in a crisis.

Our first major challenge was to find a base station small enough for a drone to support. Drones under 25 kilograms—the limit now imposed by U.S. air-safety regulators—can carry a maximum payload of about 2 kg, so we would need a base station that weighed less, even with its battery.

Finally, my search led me to a startup named Virtual Network Communications. This company, based in Chantilly, Va., sells a product called a GreenCell that seemed suitable. It’s a scalable LTE base station, known as a picocell, which is typically used to extend the reach of an existing network but can also generate its own network. The base station contains an E-UTRAN Node B radio with two antennas and a credit-card-size component called a Micro Evolved Packet Core, which uses LTE technology to form an ad hoc network with nearby radios. Then, that local network connects to a nationwide cellular network.

With these components, our GreenCell can support communications for up to 128 users at a time from a distance of up to about 2 kilometers on any LTE frequency. Better yet, it measures just 12.5 by 12.5 centimeters and weighs only 2 kg with its battery, just light enough to be lifted by a drone.

Once we had found a suitable base station, we still needed to find a suitable drone. Ideally, it would be affordable and be capable of flying for 10 to 12 hours before needing a recharge. Unfortunately, no such drone exists today. Most commercial drones can stay aloft for fewer than 45 minutes.

After some research, I found a company named CyPhy Works, which has developed a drone powered through a 150-meter cord that extends up from a grid or generator. Technically, this drone could stay in the air for as long as it had access to a power supply on the ground. But in a disaster scenario, it would have to be tethered to a van loaded with a generator and fuel. That would limit it to serving the same road-accessible places to which mobile units already travel. Another drawback: The drone’s tether restricts its mobility once it’s in the air. We wanted to be able to reconfigure our network in an instant.

We briefly considered using balloons instead of drones, but we discovered through trial and error that balloons are difficult to reposition and hold in place, especially during high winds.

We decided instead to use the AR200 drone from AirRobot, a company based in Arnsberg, Germany. The AR200 has six rotors that allow it to hover more steadily than the usual four. And because the AirRobot drone is battery powered, it can zoom off to any location.

In summer, Qualcomm unveiled [PDF report] the results of a months-long drone trial program, which found LTE networks today already provide the aerial connectivity necessary to support commercial unmanned aerial vehicle deployments. But the tech giant noted some network optimizations will be necessary to take drone deployments to new heights. As per their blog post:

During the field trial, approximately 1,000 flights were performed to collect datasets that were post processed and analyzed. We also performed simulations to complement field trial results by allowing study of performance tradeoffs when the network is serving many mobile devices and LTE-connected drones simultaneously over a wide area. Simulations also enabled rapid testing of parameter and feature changes that are more difficult to study in a commercial network.

The field trial demonstrated that LTE networks can support safe drone operation in real-world environments. Our findings showed that existing commercial cellular networks can provide coverage to drones at low altitudes up to 400 feet AGL. Our test drones also showed seamless handovers between different base stations during flights. Below is a glimpse of these findings.

According to Mobile World Live,

The head of AT&T’s Unmanned Aerial Vehicles (UAV) business development team said the operator is working with regulatory authorities and standards organisations to “unlock” the potential of drones.

Speaking with Mobile World Live, Greg Belaus said many tests of drones on cellular networks so far have been conducted at a height of 400 feet. In the US, Belaus explained that airspace is governed by the Federal Aviation Administration’s (FAA) Part 107 rules. Belaus said “a lot of work” on drones right now is focused on what needs to be done to open that area for drone services.

There is an interesting AT&T Flying COW presentation on Youtube for anyone interested, here.

#DronemanGhoshy is creating the world's first "Droneway" like you have Motorways and Railways! pic.twitter.com/4HBMGYrrmk

— Ayan Ghosh (@DronemanGhoshy) September 11, 2017

Finally, looks like "Droneway" may be becoming a reality soon. As one of the partners involved in the project, I may not be at a liberty to say much but this photo of the article below (click to expand) provides an idea 😊

*Full Disclosure: I work for Parallel Wireless as a Senior Director, Strategic Marketing. This blog is maintained in my personal capacity and expresses my own views, not the views of my employer or anyone else. Anyone who knows me well would know this.

Sprint's Magic Box

Is Sprint doing Small Cells? That's a question probably asked too many times. Back in January, their COO Günther Ottendorfer said the company’s small cell partners conducted a range of trials last year in order to determine fast and efficient methods to deploy small cells, a situation he said led to some misunderstandings in the market. However, he said those trials are largely behind the carrier and that he expects the carrier’s small cell efforts to expand this year.

“There was a learning process in 2016. We did a lot of trials in the beginning. We had some trials that led to misunderstandings, when you have a lot of boxes there because you were trialing different things, different—for example—transmission methods,” said Ottendorfer, Sprint’s chief operating officer for Technology, in a recent interview with FierceWireless. “But now we have streamlined the concepts and so I’m very confident that with streamlined and very elegant small cell solutions we will have a good rollout this year.”

They again mentioned about their small cells commitment at MWC. Finally this week, they announced the Magic Box.

Sprint has billed it as "World’s First All-Wireless Small Cell". This is a point where I would disagree with them, mainly for two reasons.The first being that for an all-wireless claim, they have to get wireless power to the small cell and secondly, this has already been done for a while. I have explained about In-band backhaul here and have provided examples of how Parallel Wireless has been using this for a while.

The Magic Box is made by Airspan and is 4G/LTE only in band 41 (2500 MHz TD-LTE). One of these units provide an average coverage of 30,000 square feet indoors and can benefit adjacent Sprint customers inside the building. The signal can also extend coverage 100 meters outside a building, benefiting customers in nearby buildings and improving street–level network performance. It does not use the closed subscriber group (CSG) feature hence anyone can camp on it and use it.

Source: FierceWireless

Sprint has a large amount of 2.5GHz spectrum available, as a result they are able to use dedicated spectrum for the Magic Box. This ensures that interference is kept to minimum. They also announced the availability of HPUE that will allow this band reach to improve. See my blog post here for details.

“It’s a far cry from just a repeater,” he said, explaining that it improves the efficiency of the network as long as it has a good connection to the macro cell. It will work with any Sprint phones using 2.5 GHz. The backhaul channel uses 2.5 GHz or 1.9 GHz, but ideally it would use 2.5 GHz because that offers a lot more capacity.

The Magic Box includes self-organizing network (SON) capabilities and operates on its own channel in Sprint’s spectrum, allowing it to decrease the noise level and increase the capacity of the overall system, which is the big difference from repeaters, explained Sprint Technology COO Guenther Ottendorfer.

Some of the details I couldn't find but hopefully some of the readers would know and can answer are:

• Whats the power output of these small cells?
• I am assuming they will support VoLTE calling for voice - even though generally that feature is transparent to small cells?
• Does the small cell radiate a single 20MHz channel?
• Does the backhaul do carrier aggregation?

Further Reading:

• Sprint Fiscal 4Q16 Results - some good insights on small cells
• CTO Blog: The World's First All-Wireless Small Cell - Sprint Magic Box
• Sprint Announces World’s First All-Wireless Small Cell – The Sprint Magic Box
• Can Sprint’s New “Magic Box” Live Up to Its Name? - Wireless Week
• Sprint introduces Magic Box, and it’s not a simple repeater - Fierce Wireless
• Sprint's new MagicBox is an LTE-A UE Relay node, made by manufacturer Airspan.

Small Cells at Mobile World Congress 2017 (#MWC17)

Mobile World Congress was big and busy, as always. There were lots of interesting demos, technologies and much more. While I was only able to look at a few demos, here is my summary of the small cells related info that I managed to see or came across on social media.

Ericsson and Philips have been working together for a while so its no surprise they were showing their new connected street lighting model. You can see this from my picture above.

Disruption at the network edge panel: @sprintnews densifying its network with thousands of small cells #mwc17 pic.twitter.com/daFoMUCz0a

— CCS (@CCS_multipoint) March 1, 2017

Sprint has already mentioned earlier that they will be rolling out more small cells and they were conveying the same message at MWC. Their rival T-Mobile says that they have 1000 small cells right now but will have 5/6000 by the end of the year.

IP Access had a nice booth and it was good to see that their CEO Malcolm Gordon and CTO Nick Johnson both managed to get their message across that 2017 will probably be a big year for Small Cells.

Vodafone introduced the "CrowdCell" concept last year, this year they continued to build on that story. The CrowdCell uses macro for backhaul. I generally refer to this as In-band backhaul (IBBH) and have written about this here. While they have already shown Indoor CrowdCell and In-car CrowdCell before, this year they were showing the Flying CrowdCell. You can see a video of that here (in Spanish) and a non-flying version here. This is slightly similar to the Airmast concept by EE.

Hidden in a corner at the Vodafone booth was a pre-commercial quad band femto by Parallel Wireless. If you look at the form factor, its no different than a single band femto from couple of years back.

Parallel Wireless also had a presence on many of their partners booths (picture above from KMW booth). TMN magazine has a feature on them and I embed their video below.


China Unicom is deploying 500 Radio Dots from Ericsson in Beijing.

Cellnex was showing how their small cells could be used for Smart Cities and Urban deployments. They have recently signed contract with JCDecaux and expects to deploy between 200,000 and 500,000 small cells 🙃

Acceleran was showing small cells on 3.5GHz CBRS band.

The Indian mobile operator Reliance Jio, which recently set a record for fastest 100 million subscribers (in 170 days), will be deploying Airspan small cells. This should be a massive project for Airspan.

Finally, there were quite a few 5G conceptual demo's. The picture above is from Intel stand. Due to 5G not yet defined, people were either using 28GHz or 60GHz. Regardless of what they were demonstrating, they would claim it to be 5G.

Apologies to other vendors I have missed.

There were also some good presentations at the Small Cell Forum networking area. The link for them is below and I will also be sharing some more of them in the coming weeks.

Related links:

• Mobile World Congress 2017 Small Cell Event Report - ThinkSmallCell
• Speaker presentations from MWC - Small Cell Forum
• Look back and forecast of Small Cells
• Flying Small Cells are here...

Operator plans for the ultra-dense network

The following is from Rethink Wireless article last month:

Large-scale deployments of public access small cells are still in their infancy, but there is already talk of 'hyper-dense' networks to cope with hotspots of intense data usage. Most of this remains just talk, but Qualcomm - on the rampage in metrocells after a hesitant start- is showing off how the approach might work in reality. 

The chip giant, never averse to a bold demonstration, is claiming the densest network ever constructed in a working environment, equating to 1,000 cells per square kilometer (a neat figure given that Qualcomm's ongoing marketing campaign revolves around the '1,000x Data Challenge', predicting an increase of that magnitude over the coming decade). 

It has put the trial together for Sprint's TDD technology, working with Airspan, the WiMAX specialist that has evolved into a small cell vendor with heavy emphasis on self-organization and integrated backhaul.

We recently heard from Caroline Gabriel in our Cambridge Wireless Small Cells SIG this (last) week. This very interesting presentation below is from that event. A very important slide is the tools that are available for achieving this ultra-dense networks. Anyway, presentation as follows:

Operator plans for the ultra-dense network from Zahid Ghadialy

Sprint’s Metrocell Move Should Bring 5 Million Shipment Bonanza By End 2013

OYSTER BAY, N.Y.--(BUSINESS WIRE)--In what is a major endorsement for public access small cells, Sprint Nextel has announced that it will deploy Alcatel-Lucent’s lightRadio Cube Metro Cell to densify its Network Vision LTE network. Sprint plans to use lightRadio metrocells starting in high traffic indoor areas such as entertainment venues, transportation hubs, and business campuses.

“This is a significant win for Alcatel-Lucent and its lightRadio technology, but more importantly dispels the notion of small cells being hyped, and that heterogeneous networks represent a major shift in mobile radio network architecture”

“We believe that this type of indoor public-access small cell will become a popular method for operators wishing to preserve spectrum and augment the data capacity of their networks while improving QoS in high traffic areas,” says Nick Marshall, principal analyst at ABI Research. Marshall adds, "We estimate total indoor and outdoor small cell shipment numbers reaching 4.55 million by end 2013, and this announcement validates that view with a high likelihood of shipments reaching closer to 5 million."