ProcessGain Solution BT / Lime Hackathon...[2] UHF Signal Leakage and Ingress - Understanding the Challenges. Ron Hranac, Nick Segura. A Technical Paper prepared for the Society of

BT / Lime HackathonProcessGain SolutionSeptember 2017

CONFIDENTIAL AND PROPRIETARYAny use of this material without specific permission of ProcessGain is strictly prohibited

Our ProfilesHernan Lopez Conde - Business Development- Industrial Engineer, Universidad de Buenos Aires- NYU Stern MBA, Class of 2007- 6y with McKinsey serving clients across South America on Strategy, Operational and Commercial topics- 1.5y with MercadoLibre as Customer Experience Director - 1.5y with Avenida.com as COO

Leandro Santi - Systems & Business Development- M Sc. Telecommunications, Universidad de Buenos Aires- Electrical Engineering, Universidad de Buenos Aires- 5y IT Architecture Mgr, Cablevisión SA- 10y Systems Engineering, Sinectis.com (later acquired by UOL)- 5y Postgraduate Professor, Universidad de Buenos Aires (current) - 15y TA Leader, Grad. School, Universidad de Buenos Aires (current)

Gonzalo Arana - Systems Development- Electrical Engineer, Universidad de Buenos Aires- 5Y TA, Linear Algebra, Universidad de Buenos Aires- 18Y of experience in Software Development + Networking- 10y Systems Engineering, Sinectis.com (later acquired by UOL)

We see a big opportunity in helping mobile operators protect their spectrum

Spectrum refarming/clearance initiatives currently being rolled out globally● High-value frequency bands re-assigned to mobile operators● Consequently, new sources of interference become relevant

According to R&S [1] [3] [4] [5], some of the most common, relevant sources of LTE interference in the US are:● Cable egress (i.e. signal leaking out from the cable network)● Bidirectional amplifiers (signal boosters, cell phone repeaters)● Spurious emissions● Wireless microphones● Fluorescent lighting● ...

● Primary source of LTE interference● Current worldwide trend: increasing frequency overlap

○ LTE operators deploying low-frequency, high-value bands (in the 900/800/700/600 MHz ranges - refarming)

○ Cable systems increasing capacity using more bandwidth and higher modulation limits. Most of the largest cable networks worldwide today transmitting well past the 750/850 MHz marks. Some of them already at 1+ GHz

Why we focused on Cable egress interference

● LTE is different than 2G/3G○ Higher data rates○ Higher order modulations○ Cleaner RF environment○ Larger channel bandwidths

● Larger cell footprint: being deployed globally in re-farmed, low-frequency bands

● Cable egress can affect both uplink and downlink channels

Cable egress can severely affect LTE performance

Current solutions

In general, LTE interference hunting in the mobile industry is largely a manual process:

● Expensive● Inefficient

Current cable egress IH efforts are done manually using portable spectrum analyzers and directional antennas (no exception)

Our solution: the μRadar

The μRadar is the first platform in the industry offering the following combination of features:

● Reduces costs, as it can be driven by a non-technical driver, with no speed constrain and aided by a navigation App

● Identifies interference hot-spots by order of relevance

● Produces non-repudiable detection outcomes● Operates passively, in stand-alone mode, completely

outside of the scope of the cable company (does not require the keys to the head-end, no need to inject proprietary reference signals for measurement)

● Fully-automates the process of cable egress interference hunting

● MVP is ready and able to scan an entire city● Field-tested by a major 4-play telecom in Argentina● SaaS Business model (we sell recurrent information not a one-time

platform)

Current development status of the μRadar

High-Level Process Architecture

Fully convergent, joint HFC/RAN interference mitigation system

● Software-based● Hybrid computing

(local, cloud)● Multi-frequency,

multi-operator● Maximum

integration capabilities (RESTful API)

High-Level Information Architecture

Maintenance system

Diagnostics, repair & claim order mgmt

Interference hot-spots id & prioritization

HFC leakage authentication & positioning

LTE coverage by operator/cell

Increasingaggregation

Time/frequency/location awareness

Field test outline

● 1.5 km2

● 2 cable operators● 2 4G 700 MHz

networks● Multiple LTE BSs in

the perimeter

Use case: egress in the LTE uplink

● This is an actual issue that was solved during a recent field-test of our platform

● A 1,100+ μV/m leak in close proximity to the BS was detected by our platform (blue arrow)

● At that point, the platform detected the street level of the leak (green dotted line)

● These kind of leaks can raise the noise floor of the BS from up to 3,000 feet away

Actual street level

Computed position

Use case: egress in the LTE uplink

● This is how the leak looked in our platform (#1)

● A second, less intense leak was hidden below the powerful emissions of #1 (#28)

● Both leaks were concurrently detected during our initial drive-test

● Both were fixed by telecom field technicians during our visit to the field

Use case: egress in the LTE uplink

Use case: egress in the LTE downlink

Cable egress map 850 MHz network

LTE coverage map 700 MHz network

Higher interference area

Right at the egress hot-spot

Negative SNR

LTE unusable, VoIP calls dropped or low quality

Lower interference area

~60 meters feet away from the egress hot-spot

Fair SNR level

Degraded LTE performance

Higher interference area

Right at the egress hot-spot

Cable egress level comparable to LTE carriers

5 MHzLTE channel

10 MHzLTE channel

10 MHzLTE channel

5 MHzLTE channel

Lower interference area

~60 meters away from the egress hot-spot

Reduced RAN SNR budget

6 MHz QAM channels 6 MHz QAM channels

LTE coverage map 700 MHz

network

Cable egress map 850 MHz network

Use case: egress in the LTE downlink

Use case: classify interference hot-spots - uplink

● This is a larger area of the city with hundreds of egress points and several 4G BSs

● We can set-up the μRadar to sort the egress points by relevance

● In the case of interference to LTE uplink, the platform matches the distance to the base station, power level of the emissions and LTE signal levels to produce a measure of relevance

Use case: classify interference hot-spots - uplink

● The streetview shows interference hot-spot #A166 of cable operator A

● Measured field strength is 132 μV/m @ 735 MHz, 10 metres away from the cable network (white arrow)

● Spot is ~50m away from the BS, with clear line of sight

● This level of field-strength can raise the noise floor of the BS from up to 400m of distance

● From ~50m, the noise floor of the BS can be degraded by ~15 dB

Use case: classify interference hot-spots - downlink

● The μRadar can also estimate the location of the interference hot-spots with the strongest degradation to the LTE downlink

● This diagram shows the SNR degradation caused by both cable networks at each point in the street

● The square markers show the estimated position of the egress spot

Use case: classify interference hot-spots - downlink

● Although there are several interference spots, LTE downlink interference is not as frequent as it is in the uplink. However, it can also be much difficult to locate using traditional techniques

Maintenance system

● Android app-based - prototype● Currently used to generate the regression set of

the HFC leakage detection & positioning code

Issues overcome/open

Solved:● Bootstrap project from scratch● Hardware prototyping & construction● HFC leakage detection & positioning● Computing/processing challenges● No limits on vehicle speed (allow 40+ mi/hr)● Mobile App leakage detection/maintenance prototype

Open:● Deploy the μRadar in production this year● Be able to detect the side (“right” vs “left”) of the location of the leak; to be

solved using LimeSDR's MIMO inputs when hardware is made available● Understand prioritary markets for this solution

Plans for taking the solution forwards

● Put our solution in production in 2017 leveraging the global trend in refarming and low-frequency use

● Finalize first contract with telecommunications company

● Plan priorities and resources according to this first contract

Summary

● We have a disruptive solution that can automate current interference hunting activities of mobile operators

● We are motivated and ready to keep evolving our solution to solve other complex issues

● We would love to engage with global leaders as BT and Lime in this innovation journey

Thank [email protected]@[email protected]

References

[1] Understanding Common Sources of Interference in LTE Networks. Paul Denisowski. Rohde & Schwarz Webinar, https://www.youtube.com/watch?v=3BkhnIErl2M (2015)

[2] UHF Signal Leakage and Ingress - Understanding the Challenges. Ron Hranac, Nick Segura. A Technical Paper prepared for the Society of Cable Telecommunications Engineers (2013)

[3] R&S Interference Hunting & Monitoring. R&S. http://www.rohde-schwarz-usa.com/IH.html (2017)

[4] Evolving Challenges in LTE/Cable Interference Issues. Paul Denisowski. Presentations and Collected Technical Papers, SCTE Cable-Tec Expo, Orlando, FL (2012)

References

[5] Recognizing and Resolving LTE/CATV Interference Issues. Paul Denisowski. Presentations and Collected Technical Papers, SCTE Cable-Tec Expo, Atlanta, GA (2011)

[6] Maximising the benefits of 700 MHz clearance. Enabling acceleration of 700 MHz clearance and use of the 700 MHz centre gap. Ofcom, https://www.ofcom.org.uk/consultations-and-statements/category-1/maximising-benefits-700mhz-clearance (2016)

[7] United States 2008 wireless spectrum auction (Wikipedia). https://en.wikipedia.org/wiki/United_States_2008_wireless_spectrum_auction

References

[8] Broadcast Incentive Auction and Post-Auction Transition. FCC. https://www.fcc.gov/about-fcc/fcc-initiatives/incentive-auctions (2017)

[9] 700 MHz auction in Canada (Wikipedia) https://en.wikipedia.org/wiki/700_MHz_auction_in_Canada

[10] Llamado a Concurso: 700 MHz. Subsecretaría de Comunicaciones (Chile). http://www.subtel.gob.cl/inicio-concesionario/llamados-a-concurso/700-mhz/

[11] LTE Interference - The New Challenge. Doug MacLeod. San Diego Chapter SCTE (2015)

References

[12] SCTE Technical Report - SCTE 209 2015 - UHF Leakage, Ingress, Direct Pickup. Engineering Committee - Network Operations Subcommittee, http://www.scte.org/SCTEDocs/Standards/SCTE%20221%202015.pdf (2015)

[13] FCC Cable Signal Leakage Guide. https://www.fcc.gov/consumers/guides/cable-signal-leakage