Cellular network with capacity transfer

ITU Regional Seminar for CIS and Europe «Development of modern

radiocommunication ecosystems»

6-8 June 2018

Russian Telecom

Equipment Company

Y. Gromakov

Doctor of Technical Sciences, Professor

Senior Vice President

Y. Borisov

Aspirant, Moscow Aviation Institute

Research Associate

Problem areas of cellular communication development: high

CAPEX/OPEX, large power consumption of sites

The cellular communications system with capacity transfer is based on changing of the network topology

without changing the generally accepted standards of cellular communications (GSM, UMTS, LTE, 5G,

etc.), using standard subscriber stations and terminals.

2

Developing markets

Rural areas

Road routes

Mountain areas

Coverage in buildings

CAPEX savings 2–3 times

OPEX savings 2–3 times

Power consumption savings 5–7 times per site

Solutions to problems of cellular communication development

Cellular communications system with capacity transfer

Principles of cellular communications system with capacity transfer

3

Cellular communications system schemes for small towns

4 base stations (BTS)

1 base station and 3 CTR

Cellular communications linear scheme

R, кмBTS2 BTS3 BTS4BTS1

R0 R0 R0 R0

41 2 3 441 2 3 4

R, км

FO

ML ML ML ML

TRX4

TRX3

TRX2

X3

X2

X1

X2

X1

X1

GSM900

BTS

DU

CTR1 CTR2 CTR3

TRX1

FRRF

Converter

FRFR

GSM900

GSM900

GSM900

PS

PS

PS

PS

TRX4

TRX3

TRX2

X3

X2

X1

X2

X1

X1

GSM900

BTS

DU

CTR1 CTR2 CTR3

TRX1

FRRF

Converter

FRFR

GSM900

GSM900

GSM900

PS

PS

PS

PS

GSM900

D U

TRX1

PSGSM900

BTS1

DU

TRX1

PSGSM900

D U

TRX1

PSGSM900

BTS2

DU

TRX1

PS GSM900

D U

TRX1

PSGSM900

BTS3

DU

TRX1

PS GSM900

D U

TRX1

PSGSM900

BTS4

DU

TRX1

PS

TRX4

TRX3

TRX2

X3

X2

X1

X2

X1

X1

GSM900

BTS

DU

CTR1 CTR2 CTR3

TRX1

FRRF

Converter

FRFR

GSM900

GSM900

GSM900

PS

PS

PS

PS

TRX4

TRX3

TRX2

X3

X2

X1

X2

X1

X1

GSM900

BTS

DU

CTR1 CTR2 CTR3

TRX1

FRRF

Converter

FRFR

GSM900

GSM900

GSM900

PS

PS

PS

PS

CTR1 CTR2 CTR3BTS1

R0 R0 R0 R0

42 3 4

R, км

1

FR

FR

FR

FO

Standard cellular communications

system

Cellular communications

system with capacity transfer

FO

F

The capacity transfer scheme is applicable for any cellular communication standards (GSM, UMTS, LTE, 5G,

etc.). The cellular communication systems with capacity transfer equipment (CTR) are compatible with base

stations of any vendor (Ericsson, Nokia, Huawei, ZTE etc.)

n CTR - Capacity Transfer

Radio

n FO - Fiber-Optic (ВОЛС)

n RC - RF convertor

CTR CTR CTR CTR CTR

CTR CTR CTR CTR CTR

CTRCTRCTR CTR

CTRCTR CTR CTR CTR

CTR CTR CTR CTR CTR

FO

FO

CTR CTR CTR

CTR CTR

CTR CTR CTR

BS

Cellular communication system with capacity transfer and option unit

at the base station

4

The option unit at the bearing base station replaces high-power (20-40 W) transceivers of the standard

base station (TRX), with low-power (0.2-0.5 W). The use of the option unit eliminates the need for the use

of a radio frequency converter RC and a microwave link (ML), since it generates a cellular signal at relay

frequencies (for example, 6-20 GHz). As a result, the cost of a bearing base station with an option unit and

its power consumption is significantly lower compared to the previous version of the capacity transfer

scheme using a standard base station with standard transceivers with a power of 20-40 W.

a)

b) CTR1 CTR2 CTR3 BTS

R0 R0 R0 R0

1 2 3 4

R, км

FO

X 3

X 2

X 1

X 2

X 1

X 1

GSM

900

BS

DU

CTR1 CTR2 CTR3

TRX1

F R F R F R

GSM

900

GSM

900

GSM

900

PS

PS

PS

PS

F R

F R

F R

2 3 4

0.2–0.5 W Option unit

n CTR – Capacity Transfer Radio

C-RAN Cellular communications system with capacity transfer

The number of Fronthaul fiber-optic (FO) lines is reduced by N times, where N is the number of

sites in the communication scheme (25 times in the presented case).

RRH RRH RRH

RRH RRH RRH

RRH RRH RRH

RRH RRH RRH

RRH RRH RRH

RRH

RRH

RRH

RRH

RRH

RRH

RRH

RRH

RRH

RRH

BBU

Core Network

BBU

F r o n t h a u l

B a c kh a u l

CTR CTR CTR

CTR RRH CTR

CTR CTR CTR

CTR

CTR

CTR

CTR

CTR

CTR

CTR

CTR

CTR

BBU

Core Network

BBU

F r o n t h a u l

B a c kh a u l

CTR CTR CTR CTR

5

Standard cellular communications system Cellular communications system with capacity transfer (CTR)

The reduction of the number of inter-cell handover and transport channels

(FO, ML) in the city

6

In a city, where the radius of the cell is 100-400 m, the quality of the communications determined largely by

the number of handovers. Use of the technology of capacity transfer in the presented scheme with CTR

reduces the number of inter-cell handover by 18 times, the area of the handover zone is reduced by 36

times.

Standard cellular communications system

Cellular communications system with capacity transfer (CTR)

handover directions

Core Network Core Network

Topology of cellular communications system with capacity transfer (1/2)

7

The cellular communications system with capacity transfer opens the possibility of use a flexible network

topology on the basis of the possibility of a chain connection of the CTR with each other and with the base

station, provides a reduction in communication disruptions, improved quality of service, providing coverage

in buildings, as well as in subways and underground premises without a handover with above-ground

network.

Standard cellular communications system Cellular communications system with capacity transfer

1 base station (BS) + 6 CTR 7 base stations (BS)

5 base stations (BS) 1 base station (BS) + 4 CTR

Topology of cellular communications system with capacity transfer (2/2)

8

The replacement of the standard connection of each base station to the Core Network via fiber optic link with the CTR communication scheme – connection of the bearing base station to CTR via the relay channel, significantly reduces the number of inter-cell handovers, increasing the reliability and quality of communications.

1 base stations (BS) + 6 CTR

7 base stations (BS) + 6 spans FO/ML

Core Network

Core Network

Base station service

area

Base station service

area

50-60 km

Standard cellular communications

system

Cellular communications

system with capacity transfer

CTR CTR CTR CTR CTR

CTR CTR CTR CTR CTR

CTRCTRCTR CTR

CTRCTR CTR CTR CTR

CTR CTR CTR CTR CTR

BS

Integrated system of satellite and cellular communication with capacity

transfer

The integrated system allows to significantly reduce the requirements for on-board equipment of the

satellite communication system due to the use of ground tracking antenna systems with a narrow beam

pattern (high gain) combined with a bearing base station of cellular communication system with capacity

transfer.

Provides communication with mobile subscribers in buildings,

Local traffic from mobile subscribers remains in the cluster of the bearing cellular base station,

Cheap cellular terminals might be used.

9

BTS2 BTS3 BTS4BTS1

R0 R0 R0 R0

41 2 3 441 2 3 4

R, км

CTR1 CTR2 CTR3BTS1

R0 R0 R0 R0

42 3 4

R, км

1

FR

FR

FR

4 Base Stations, 4 Satellite Terminals

1 Base Stations, 1 Satellite Terminal,

3 CTR

Communication scheme for rural

Linear network diagram

Cellular communication systems with capacity transfer for creating of

local zones in emergency situations

10

Cellular Network GSM/UMTS/LTE

Satellite Gateway

Teleport

Cellular Base Station

Characteristics Value

Max payload 20 kg

Max. Lifting height 100 м

Lifting time to a height of 100 m 30 s

Dimensions (length * width * height) 1,6*1,6*0,2 м

Flight time Unlimited

R -8-10 km CTR

CTR

CTR

CTR

CTR

BS

The use of the cellular communication system with capacity transfer

simultaneously by several operators (RAN Sharing)

11

BTS

1

BTS

BTS

2 3 123

BTS

BTS

BTS50 – 60 km

The ability of CTR to work with base stations of any vendor allows to implement a communication

scheme with capacity transfer simultaneously for several operators.

For each of the 3 operators provides:

6 base stations of cellular communication and 6 microwave links (ML) replaced with 6 shared CTRs;

the number of towers and sites reduced 3 times;

energy consumption per the site reduced 5-7 times;

light masts used;

significantly accelerated the construction of the network.

Scheme of the joint RAN Sharing test zone

(Operators «A» and «B»)

12

Operator «A»

The installation of CTR, shared by 2 operators, using common towers for all operators, allows to reduce the

use of standard base stations and to provide multiple expansion of coverage areas and capacity of the

network.

Operator «B» RAN Sharing

The use of CTR to provide continuous coverage of the road route for 2 operators

n RC – Radiofrequency Convertor

CTR2

CTR1

CTR1 RC1

RC2

Effectiveness of cellular communications system with capacity transfer

use for different communication schemes

13

Communication scheme Cost reduction (BS /

CTR) for network

fragment

RAN

Sharing

opera-

tors

Cost reduction (BS /

CTR) for network

fragment, for each

operator

BS based CTR based Equip-ment

Electri-city

Equip-ment

Electri-city

Linear 3 sites

2,0 2,3

2 3,4 2,6

3 3,8 2,6

Linear 5 sites

2,4 3,1

2 4,1 3,6

3 4,5 3,6

Linear 7 sites

2,6 3,6

2 4,4 4,2

3 4,8 4,2

Rectangular 9 sites

2,2 4,0

2 5,0 5,1

3 5,5 5,1

Rectangular 25 sites

2,4 5,2

2 5,6 7,0

3 6,1 7,0

CTR BS CTR

CTR1 CTR2 CTR3

CTR4 CTR5

CTR6 CTR7 CTR8

BS

CTR7 CTR8 CTR9

CTR12 CTR13

CTR16 CTR17 CTR18

BS

CTR1 CTR2 CTR3

CTR20 CTR21 CTR22

CTR4 CTR5

CTR23 CTR24

CTR10

CTR14

CTR19

CTR6

CTR11

CTR15

BS BS BS

BS BS BS BS BS

BS BS BS BS BS BS BS

BS BS BS

BS BS

BS BS BS

BS

BS BS BS

BS BS

BS BS BS

BS

BS BS BS

BS BS BS

BS BS

BS BS

BS

BS

BS

BS

BS

BS

CTR BS CTR CTR CTR

CTR BS CTR CTR CTR CTR CTR

Results of GSM 900 cellular communications system with capacity

transfer tests at commercial network of operator «A»

The tests showed that the characteristics of the GSM network fragment built on the basis of CTR are not

inferior to the characteristics of the network fragment built on the basis of standard base stations, both in

mesures of the created coverage and quality of service.

The power consumption of the radiofrequency converter RC is not more than 100 W, and the power

consumption of the CTR in the maximum configuration (6 frequency channels) is not higher than 320 W.

14

Commercial network

coverage area

CTR coverage area

High signal level

Low signal level

CTRs are installed on the

sites of base stations of

the commercial GSM 900

network

GSM 900 cellular communications system with capacity transfer tests

15

GSM 900 6 channels CTR

General view of BTS site power consumption around 5 kW

General view of CTR site power consumption up to 320 W

Six-channel CTR on mast of operator «A» at Kirov town

3x sector UMTS or LTE CTR

power consumption 180 W power consumption 320 W

Recommendation ITU-T L.1700 Supplement 30 and

invention patents

Russia USA Europe

China India

16

Ukraine