Commscope: Antennas Solutions for Capacity Improvement - June 2014

Antennas Solutions for Capacity Improvement

Kevin Linehan June, 2014

Copyright © 2014 CommScope, Inc. – All rights reserved.

2PRIVATE AND CONFIDENTIAL. Copyright © 2014 CommScope, Inc. – All rights reserved.

Topics

• Introduction

• BSA evolution and trends

• Capacity Solutions –BSAs

• BSA standards


SECTORIZEDOMNI DIRECTIONAL

• Increases capacity• Beamwidths 65, 90,105• Coverage shaping

• Mechanical tilt• El beamwidth

� Radiates equally� x2 for RX spatial diversity

1983 1989

• Single BSA for both RX diversity arrays

• Dual, slant 45 polarization replaces vertical pol

1997

DUALPOL

BSA Evolution and Trends


ELECTRICAL TILT & RET MULTI- & BROAD- BAND

• Covers wider bandwidth• More arrays in a radome• Minimizes visual impact

• Coverage superior to mechanical tilt

• Remote Electrical Tilt avoids tower climbs

• RX diversity

2001 2003


LTE & MIMO

• 2X2 MIMO on the DL• 4 RX diversity – HB diversity• 4X2; 4X4 MIMO upgradable

Now


TD-LTE BEAMFORMERS


One Twin Beam BSAOne 65° BSA

1 sector 2 sectors

MULTI-BEAM

• Two beams from one BSA• Each beam dualpol• Planar array with Bulter matrix• Beams have individual downtilt

• Planar Array• WiMax ► TD-SCDMA ► TD-LTE• 4 port v-pol ► 8 port dual-pol ► RET


Macro-cell integration: RF into the antenna

HetNet



What Are Today’s

Antenna Solutions to

Capacity Challenges?

What Are Today’s

Antenna Solutions to

Capacity Challenges?


Capacity Resources

increased spectral efficiencyadditional spectrum

densification

Moray Rumney. Smart Cells and Wireless Capacity Growth. PowerPoint Presentation for Agilent Technologies in LTE World Summit, Posted Online May 26, 2010

Historically

dominated by an

increase in

cells/sectors .

20 25

2,000

SpectralEfficiency

Spectrum No. ofCells/Sectors

Growth Factor


Capacity is Determined by SINR

Maximum throughput requires:

• Interference Reduction and Optimization

• Noise Suppression in the RF path

• Sector Sculpting

• Load Balancing

Motorola Whitepaper: Realistic LTE Performance –

From Peak Rate to Subscriber Experience, 2009


The design goal of a shaped beam is to:• Direct maximum energy into the illuminated• Minimize interference into all other sectors

Antenna Pattern Quality is Key to Good SINR

* Typical horizontal BW antenna patterns from initial

deployments of GSM/UMTS

90º Antenna

65º Antenna

High Performance 65º Antenna

• Theoretical site geometry• Real antenna pattern


Sector Sculpting - Horizontal Pattern

Standard 90 ° BSAHigh Performance –5dB

80°

–12dB

–25dB

–5dB

90°

–10dB

–18dB

–40dB –25dB

Roll offat –/+ 60°

–10 dBpoints

Front-to-Side Ratio

Next SectorAnt/AntIsolation

Front-to-Back

Ratio

Key characteristics


Sector Sculpting - Elevation Pattern

Key characteristics

SidelobeSuppression

Main LobeMain Lobe


Antenna Height Tilt Outer Measure at -3dB

20 ft. 20 deg. 103 ft.

20 ft. 16 deg. 175 ft.

40 ft. 16 deg. 350 ft.

Beam Tilt & Side Lobe Suppression of Metro Cells

Desired Metro Cell Vertical Beam Pattern

12- 20º

Horizon (0º)

Control over upper side lobes keeps RF interference out of nearby buildings and other cells

Point of greatest interference(lowest SINR) should be well-defined


Three Simulations of Metrocell HetNets

• Monte Carlo RF Planning Tool– Cluster of cell sites simulated – Dense urban– UE is located randomly 1000’s of times

• Poisson Point Process Simulation– UT Austin- cells are random PPP– UE is located at the origin point– Network is created 1000’s of times

• Monte Carlo - Matlab Simulation– Bias and Load balancing considered– Typical load on network at 50%


Summary

• Impact of vertical beamwidth– Without down tilt, average spectral efficiency decreases as the vertical

beamwidth of small cell antenna decreases (beam reaches deeper into network, lowering SINR)

• Improved University of Texas model using Poisson distribution with 3D calculations and Atoll both confirm improvements of antenna tilt

• Impact of antenna down tilt– Average spectral efficiency is improved approx. 40% over standard omni

• Recent studies indicate with load balancing there is an optimum tilt balancing small cell off load and HetNet intereference

Control over Vertical Beamwidth and Down Tilt Matter s!Control over Vertical Beamwidth and Down Tilt Matter s!


MetroCell Quasi-Omni BSA

• Three 65°BSA’s combined• Dual Band, DualPol• Electrical Tilt & RET• Uppersidelobe suppression• Sectorizable


Multi-Beam BSAs to Increase Capacity

• More capacity due to increased sectorization

• Ideal solution for high traffic sectors and events

• Extends value of existing cells

• Fast and easy deployment

2 Beams(2 x 38°)

5 Beams(5 x 12°)

9 Beams(9 x 6°)

18 Beams(2 x 9 x 6°)

3 Beams(3 x 24°)


View from behind antenna looking outward:

9.4°

8°

~90°

2x9-Beam Antenna


BSA Standardization Benefits

� Reduces ambiguity � Reduces miscommunication � Facilitates cost / benefit decisions� Drives higher quality and performance


Example Specification: Front to Back Ratio

Front to Back (F/B) is a single sided specification


Front-to-Back Ratio

• There are many ways to specify Front-to-Back Ratio, which varies with frequency and tilt• Typical F/B Co-pol only at 180 degrees: This is the default industry standard• BASTA: Total Power (Co + Cross-pol) over 180±30 degrees across tilts and frequencies


Gain Specification

• There are many ways to specify gain, which varies with frequency and tilt• Maximum (or near maximum) gain: This is the default industry standard• Minimum gain: desired by some customers, no vendor uses• BASTA: average value across tilts and frequencies


Thank-you!

Questions?


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Commscope: Antennas Solutions for Capacity Improvement - June 2014

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