BBU

KDDI R&D LABS, Panasonic, Osaka University, Tokyo Institute of Technology (JP) Fraunhofer Heinrich-Hertz-Institut, Intel Mobile Communications, Commissariat à l’Energie Atomique, Orange Labs, Politechnico di Milano (EU)

Project website: http://www.miweba.eu/

Prototype of Control and User plane splitting Heterogeneous Cellular Networks

Concept & Architecture of C/U-splitting HetNet*

Prototype of C/U-splitting HetNet

C-plane

Macro cell

Traditional cellular bands New frequency bands Frequency

UHF SHF Millimeter-wave Background

Concept of C/U-splitting HetNet

* HetNet: Heterogeneous Networks

700MHz – 3.5GHz 6GHz – 70GHz

Propagation Characteristics Available Bandwidth

Good low penetration loss

mm Small cell Large bandwidth

x Dense deployment Extreme capacity

(for user data) User(U)-plane

data

Low frequency Connectivity (for control)

Split!

Serving GW

Cellular

WiGig eNB

MME

WiG

ig

Service Network

X2 interface

Architecture of MiWEBA prototype using LTE and WiGig (under development)

Architectural alternatives • Single-RAT solution

• Multi-RAT solution

mm

Small WiGig

PHY&MAC

Wrapper function

LTE eNB

Master eNB ／RRC

Macro LTE

PHY&MAC

Secondary eNB

Centralized Mobility Control & Radio

Resource Management

LTE (<6GHz)

LTE (<6GHz)

Antenna

LTE (6-70GHz)

Unified architecture of LTE-Advanced (LTE-A) and Further enhanced LTE-A

(including both licensed and license-assisted unlicensed spectrum)

Interworking between Multiple Radio Access Technologies (RATs)

(including further enhanced LTE, Wi-Fi, WiGig or New 5G RAT )

LTE BBU

BBU LTE BBU

Centralized BBU

ORI fronthaul

LTE backhaul (e.g. S1, X2)

PHY&MAC should be revised for mm-wave

Service Network

Core Network (EPC)

ORI: Open Radio Interface LTE: Long Term Evolution BBU: Baseband Unit EPC: Evolved Packet Core RRM: Radio Resource Management

C/U-splitting within Centralized BBU or between BBU via X2

LTE (<6GHz)

WiGig (60GHz)

New RAT (-70GHz)

Service Network

BBU

LTE BBU

WiGig BB

New RAT BBU

Core Network (EPC)

Multi-RAT RRM

C/U-splitting between Multiple RATs

Development plan C/U-splitting HetNet using LTE • FY2013 (Finished)

• FY2014-FY2015 (Under development)

BBU+RF

Conventional BS

UE

LTE Macro cell LTE Small cell

MME/S-GW

(2GHz) (3GHz)

U-plane

Fading Simulator

LTE Macro cell

LTE Small cell

(2GHz)

(3GHz)

Fading Simulator

C/U-splitting HetNet using LTE (2GHz/3GHz)

UE

ORI fronthaul with I/Q compression

RRH

LTE eNB

WiGig eNB

mm mm mm

WiGig Small cell (60GHz)

Control(C)-plane signaling

LTE eNB

Indoor Air

C/U-splitting HetNet using LTE and WiGig

UE BBU+RF

MME/ S-GW

Fading Simulator

LTE eNB

• Developed hardware

Macro cell (2GHz) Small cell (3GHz)

• Throughput test result while moving UE

02468

1012

0 2 4 6 8 10 12 14 16 18 20

Thro

ughp

ut[M

bps]

Time[s] Total (C/U splitting)Macro cell (C/U splitting)

Move UE from Macro to Small

Control plane signaling sent from Macro cell

UE receives the U-plane data from small cell, while keeping the C-plane handled by macro cell

Switch without interrupt

Parameter Value Radio Access DL: OFDMA

UL: SC-FDMA DL Carrier freq. Macro: 2160MHz

Small: 3385MHz DL bandwidth 10MHz Antenna conf. 1x1 (SISO) Radio access technology

LTE based

Poor heavily utilized

Tricky high penetration loss

Rich not utilized for mobile

Get the advantages of both bands

Centralized Control