In this presentation we discuss the following topics surrounding fronthaul: 1. Why fronthaul? 2. Capacity requirements 3. Latency requirements 4. Fronthaul and small cells 5. Transport for Fronthaul

1. 5 THINGS YOU
SHOULD KNOW
ABOUT
FRONTHAUL

2. AVIAT NETWORKS
AGENDA
1) WHY FRONTHAUL?
2) CAPACITY REQUIREMENTS
3) LATENCY REQUIREMENTS
4) FRONTHAUL AND SMALL CELLS
5) TRANSPORT FOR FRONTHAUL

3. AVIAT NETWORKS
WHY FRONTHAUL?

4. AVIAT NETWORKS
THE DATA STORM
Growth from 1.6 EB per month in 2013
to 11.2EB in 2017 (66%)*
CAPACITY GROWTH
HANDHELD DEVICES
NETWORK COSTS
MOBILE BROADBAND
By 2017 there will be an increase
on 67% in handheld devices*
CAPEX will increase worldwide by 6% in
2014 to $104.5 billion**
1.5 Billion Mobile Broadband
Subscribers Predicted By 2015**
*Source: Cisco Visual Networking Index
**Source ABI Research

5. AVIAT NETWORKS
DENSER NETWORKS
This has several problems:
 How to meet the required coverage
and capacity?
 How to deal with interference?
 How to manage increased complexity:
 To increase spectral efficiency?
 To manage customer’s data?
 To deal with higher CAPEX and
OPEX?
the only way to deal with the data storm is to
have denser wireless networks with
increasing spectral efficiency

6. AVIAT NETWORKS
STRATEGIES FOR DENSER NETWORKS
RAN DECENTRALIZATION (SON, HETNETS)
TRADITIONAL MACRO CELLS
ALL IN ONE BBU / SMALL CELLS
BACKHAUL
RAN CENTRALIZATION (C-RAN)
DISTRIBUTED ANTENNAS (DAS)
REMOTE RADIO HEADS (RRH)
FRONTHAUL
WiFi OFFLOAD
OFFLOAD

7. AVIAT NETWORKS
WHAT IS FRONTHAUL?
‘CENTRALIZED’ OR ‘CLOUD’ - RAN

8. AVIAT NETWORKS
BASE STATION SPLIT
SYSTEM SOFTWARE
POWER SYSTEM
BASESTATION
TRANSPORT MODULE BASE BAND
MODULE
RF MODULE
CONTROL MODULE
FRONT HAUL
BBU / DU
(REC CPRI)
digital base band
RRH
(REC CPRI)
analog frequency functions
NETWORK
INTERFACE
AIR
INTERFACE

9. AVIAT NETWORKS
ADVANTAGES OF C-RAN
 Resource pooling
 Greener infrastructure (re-use)
 Base station virtualization
 Simplified management and operation
 Coordination for interference mitigation (ICIC)
 Multi technology support
 No GPS in each remote site

10. AVIAT NETWORKS
MAIN C-RAN CHALLENGE IS FRONTHAUL
 High capacity low latency Fronthaul is needed
 Fronthaul distance is limited due to latency
 Base band interconnection in BBU hotel
 Lack of management tools on Fronthaul links
 No statistical multiplexing on Fronthaul links

11. AVIAT NETWORKS
C-RAN offers many benefits for
operators however Fronthaul challenges
need to be addressed
Takeaway:

12. AVIAT NETWORKS
CAPACITY REQUIREMENTS

13. AVIAT NETWORKS
CPRI- NO COMPRESSION
WCDMA
5 MHz 10 MHz 20 MHz
3 Sector, 4x4
MIMO, 1 Carrier 922 Mbps 7.4 Gbps 14.7 Gbps
1 Sector, 2x2
MIMO, 1 Carrier 246 Mbps 1.2 Gbps 2.5 Gbps
LTE
Scenario

14. AVIAT NETWORKS
COMPRESSION OF BASEBAND USER DATA
 Multiple baseband compression
techniques are currently being
researched
 Commercially available IQ
compression causes some
distortion in IQ constellation
 IQ compression currently is below
a ratio of 3 to 1

15. AVIAT NETWORKS
CPRI- COMPRESSION (2.5 RATIO)
WCDMA
5 MHz 10 MHz 20 MHz
3 Sectors, 4x4
MIMO, 1 Carrier 369 Mbps 2.9 Gbps 5.9 Gbps
1 Sector, 2x2
MIMO, 1 Carrier 98 Mbps 461 Mbps 983 Mbps
Scenario
LTE

16. AVIAT NETWORKS
Compression will likely be required to
make wireless CPRI Fronthaul a reality
Takeaway:

17. AVIAT NETWORKS
LATENCY REQUIREMENTS

18. AVIAT NETWORKS
CPRI-ROUND TRIP LATENCY (LTE)
“cable length latency”
+
CORECPRI
BBU
TRANSMISSION MEDIUM
(FIBER / MICROWAVE)
RRH
IP BACKHAUL
RRH
CPRICPRI
B
C
A
A B C+TOTAL LATENCY=
}
FOR CPRI= 5 µs
STANDARD
DEPENDENT
FOR LTE (100/200 µs)

19. AVIAT NETWORKS
CPRI latency requirement (<200us) will
demand the use of ultra low latency
Fronthaul solutions
Takeaway:

20. AVIAT NETWORKS
FRONTHAUL AND SMALL
CELLS

21. AVIAT NETWORKS
EXPANSION USING FRONTHAUL + SMALL CELL
CELL SPLIT USING FRONT HAULTRADITIONAL MACRO CELL DEPLOYMENT
Source: NGMN

22. AVIAT NETWORKS
TRADITIONAL DEPLOYMENT + SMALL CELL (BACKHAUL)
TRADITIONAL MACRO CELL DEPLOYMENT MACRO CELL + SMALL CELL DEPLOYMENT
Source: NGMN BACKHAUL

23. AVIAT NETWORKS
Operators will use a combination of
CRAN/RRH and Small Cells
Takeaway:

24. AVIAT NETWORKS
TRANSPORT FOR
FRONTHAUL

25. AVIAT NETWORKS
FIBER / MICROWAVE FRONTHAUL COMPARISON
FIBER 70/80 GHz MICROWAVE
LICENSED MICROWAVE
(6 to 42 GHz)
CAPACITY:1 SECTOR,10MHz, 2x2 MIMO, 1
CARRIER, NO COMPRESSION
CAPACITY:1 SECTOR,10MHz, 2x2 MIMO, 1
CARRIER, COMPRESSION: 2.5
LATENCY
Capacity
WDM self seeded
PON 1 fiber upto 10
Gbps per RRH
2.5 Gbps 1.2 Gbps
LOS LOS
Parabolic antenna Parabolic antenna
LINK LENGTHS Maximum 40Km Maximum 2Km Maximum 60Km
LATENCY 5 µs per Km
3 µs per Km +
processing (between
5µsec and 50µsec)
3 µs per Km +
processing (between
60µsec and 298µsec)
CAPEX Very high Medium Medium
OPEX Low Low Low
SOLUTIONS
SITE LOCATION /RESTRICTIONS Right of way issues
REQUIREMENTS
1.2 Gbps
461 Mbps
<200 µs for LTE

26. AVIAT NETWORKS
Single channel compressed CPRI is the
most likely application for centimeter
wave microwave Fronthaul
Takeaway:

27. AVIAT NETWORKS
1. C-RAN offers many benefits for operators
however Fronthaul challenges need to be
addressed
2. Compression will likely be required to make
wireless CPRI Fronthaul a reality
3. CPRI latency requirement (<200us) will
demand the use of ultra low latency Fronthaul
solutions
4. Operators will use a combination of
CRAN/RRH and Small Cells
5. Single channel compressed CPRI is the most
likely application for centimeter wave
microwave Fronthaul
CONCLUSIONS

28. W W W . AV I AT N E T W O R K S . C O M