review of current macro network site types and designs · 2019. 5. 13. · • lte • adding even...

Review of current macro network site types and designs

Andy Sutton

Principal Network Architect

Architecture and Strategy, BT Technology

9th May 2019

British Telecommunications plc 2018

Contents

• High-level macro-cell design consideration

• Macro-cell site evolution:

• GSM

• Space and polarisation diversity

• UMTS

• Introduction of network sharing

• LTE

• Adding even more frequency bands

• 5G macro-cell trials and site design

• 5G demos

• Summary


High-level macro cell site design considerations

3

Site acquisition and lease agreement

Structure

Antenna system

Electricity supply

Cabin / enclosure

Feeder system*

Mobile backhaul

Earthingsystem

EMFICNIRP

* Includes fibre and DC power in addition to coaxial transmission line - dictated by location of Radio Units


GSM - a massive civil engineering programme

4


Single band GSM antenna system

5

• Space diversity receive systems and tower mounted low noise amplifiers

improved the uplink (prior to polarisation diversity systems)

• Prior to the Bias-T implementation, a separate DC power cable would be

installed between a power distribution unit in the cabin and each amplifier

•Single transmit antenna illustrated however dual duplex configuration was

implemented by some vendors/operators to scale capacity

•Antennas had fixed electrical tilt, mechanical tilt was a common RF

optimisation technique, early sector antennas had wide beam-width

Duplex Filter

RF Combiner Rx Multi-Coupler

Transmitter(s) Receiver(s) - Primary

Bias T

MHA

-

LNA

Duplex Filter

Duplex Filter

Amp


Space and polarisation diversity systems

6

≥10λ


Space and polarisation diversity systems

7


UMTS - different approaches - single band or dual band antennas…

8


Structures and antenna systems

9 Dual band single polarisation

(space diversity)

Dual band cross polarisation

(polarisation diversity)

Dual band cross polarisation


Single band cross polarisation



GSM 1800 and UMTS 2100 antenna system

• Dual band cross polarisation antennas

• 1800MHz

• 2100MHz

• Single port MHA for UMTS 2100

• Dual port MHA for GSM 1800

• 4 Coaxial feeder cables per cell sector

• Microwave radio for backhaul connection

10


Example site configurations for shared GSM/UMTS site

11

#1 – MNO

with 2G & 3G

#2 – MNO

with 3G only

Combiner

3G#2

3G#1

2G#1

Single MHADual MHA

1800 MHz 2100 MHz

1800 MHz

Cross

polarisation

antenna

2100 MHz

Cross

polarisation

antenna

Combiner

3G#2

3G#1

2G#1

Dual port

dual band

MHA

1800 MHz 2100 MHz

Wide-band

Cross

polarisation

antenna


Adding 4G LTE…

12


Providing DC power and fibre (fronthaul) to external remote radio units

13


LTE adds more frequency bands

14

• Antenna systems must support

the following frequency bands:

• 800 MHZ

• 1800 MHz

• 2100 MHz

• 2600 MHz

• Note the misalignment between

antenna ports colour scheme and

feeder tags, this is by design, our

(MBNL) colour scheme came

first…


Multi-band, multi-RAT, multi-operator antenna system

15

LNA

Combiner

3G#2

3G#1

4G#2

1800MHz 2100MHz

4G#1

LNA

4G#1

2600MHz800MHz

RRH

4G#2

Combiner

2G/4G

#1

LNA

Dip.

1800MHz

Optical fibre cables

and DC power

Note: There are

many possible

solutions to this

radio configuration,

including separate

antennas.

Could be 2T2R,

2T4R as implied in

this diagram, or 4T4R


Introducing 5G @ 3500 MHz - radio trials with 8T8R and 64T64R systems

16


5G demo at Canary Wharf

17

Highlights• 1.3Gbps to test equipment (30 MHz LTE + 40 MHz NR)• 600Mbps to Huawei 5G CPE (5 MHz LTE + 40 MHz NR)• 4T4R LTE (15 MHz 2100 + 15 MHz 2600) with 64T64R NR


Summary

• Macro-cells have provided the vast majority of cellular coverage and capacity for many

years - a trend which will continue with 5G• Small cells will have a significant role to play in the fulness of time

• Macro-cells are a cost optimised solution for delivering 5G to a large geographically

dispersed subscriber base

• Site solutions need to be plug and play, simple installation requirements results in less

errors - get it right in one visit!

• Solutions between 8T8R and 64T64R are required, 16T16R and 32T32R use cases

• Single passive antenna for all radios is required on some sites

• Hybrid active/passive antennas will be a solution for some sites

• More than two antennas per sector is a challenge - 1 x active and 1 x passive at most

• This presentation has focused on one aspect of macro-cell design, there are many

other considerations…

• 5G TDD radio interface requires frequency and phase sync, this must be resilient

• 5G will drive significant upgrades to transmission - fronthaul, midhaul and/or backhaul

• BT/EE is actively upgrading its macro-cell footprint in accordance with our 5G rollout

plans

18


Thank YouAny questions?

19

review of current macro network site types and designs · 2019. 5. 13. · • lte • adding even...

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