Review of current macro network site types and designs
Andy Sutton Principal Network Architect Architecture and Strategy, BT Technology 9th May 2019 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
British Telecommunications plc 2018 High-level macro cell site design considerations
Earthing EMF system ICNIRP
Antenna Mobile system backhaul
Structure Feeder system*
Electricity Cabin / supply enclosure
Site acquisition and lease agreement
* Includes fibre and DC power in addition to coaxial transmission line - dictated by location of Radio Units
3 British Telecommunications plc 2018 GSM - a massive civil engineering programme
4 British Telecommunications plc 2018 Single band GSM antenna system
Duplex Filter
MHA - Amp LNA
Duplex Filter Bias T
Duplex Filter • 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
RF Combiner Rx Multi-Coupler 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 Transmitter(s) Receiver(s) - Primary optimisation technique, early sector antennas had wide beam-width
5 British Telecommunications plc 2018 Space and polarisation diversity systems
≥10λ
6 British Telecommunications plc 2018 Space and polarisation diversity systems
7 British Telecommunications plc 2018 UMTS - different approaches - single band or dual band antennas…
8 British Telecommunications plc 2018 Structures and antenna systems
9 British Telecommunications plc 2018 Dual band single polarisation Dual band cross polarisation Dual band cross polarisation Single band cross polarisation (space diversity) (polarisation diversity) (polarisation diversity) (polarisation diversity) 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 British Telecommunications plc 2018 Example site configurations for shared GSM/UMTS site
1800 MHz 2100 MHz Wide-band #1 – MNO Cross Cross Cross with 2G & 3G polarisation polarisation polarisation #2 – MNO antenna antenna with 3G only antenna
Dual port Dual MHA Single MHA dual band MHA
Combiner Combiner
2G 3G 3G 2G 3G 3G #1 #1 #2 #1 #1 #2 11 British Telecommunications plc 2018 1800 MHz 2100 MHz 1800 MHz 2100 MHz Adding 4G LTE…
12 British Telecommunications plc 2018 Providing DC power and fibre (fronthaul) to external remote radio units
13 British Telecommunications plc 2018 LTE adds more frequency bands
• 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…
14 British Telecommunications plc 2018 Multi-band, multi-RAT, multi-operator antenna system
Note: There are many possible solutions to this radio configuration, including separate antennas.
Could be 2T2R, 2T4R as implied in this diagram, or 4T4R
RRH LNA LNA LNA
Optical fibre cables Combiner Combiner Dip. and DC power
4G 3G 3G 4G 4G 2G/4G 4G #2 #1 #2 #1 #2 #1 #1 15 British Telecommunications plc 2018 1800MHz 2100MHz 800MHz 1800MHz 2600MHz Introducing 5G @ 3500 MHz - radio trials with 8T8R and 64T64R systems
16 British Telecommunications plc 2018 5G demo at Canary Wharf
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
17 British Telecommunications plc 2018 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 British Telecommunications plc 2018 Thank You Any questions?
19 British Telecommunications plc 2018