1 ©  Roke Manor Research 2002 Roke Manor Research RC/DWS/Japan Wireless Technology Beyond 3G In Japan Dave Smith

2 ©  Roke Manor Research 2002 Roke Manor Research RC/DWS/Japan Technology Evolution

3 ©  Roke Manor Research 2002 Roke Manor Research RC/DWS/Japan  Requirement  100Mb/s  Wide area  By 2010 How?  USA – WLAN  Europe – convergence  Japan – new air interface Datarate is the Goal

4 ©  Roke Manor Research 2002 Roke Manor Research RC/DWS/Japan What are key technologies ?  Telecommunications Council Report 2001  New air interface  Software Defined Radio  Adaptive Array Antennas  High level modulation schemes  Dynamic link adaptation

5 ©  Roke Manor Research 2002 Roke Manor Research RC/DWS/Japan What are the key technologies?  Telecommunications Council Report 2001  New air interface  Software Defined Radio  Adaptive Array Antennas  High level modulation schemes  Dynamic link adaptation  MIMO  Direct Conversion receivers

6 ©  Roke Manor Research 2002 Roke Manor Research RC/DWS/Japan Access Scheme  4-5 GHz  NTT DoCoMO defined access scheme  (referenced 4 year study)  OFDMA vs MC –CDMA

・ For Seamless Area Coverage, Multi-cell Structure is necessary. CDMA can achieve the best spectrum efficiency. ・ For High Throughput, Single-cell Structure is suitable because it can avoid inter-cell interference. OFDM can achieve the best spectrum efficiency. Current Multiple Access Technologies 2002 c NTT DoCoMo 7 But ･････ - Each scheme is not best in the other cell structure. - For the flexible area coverage and service deployment with lower cost, both Multi-cell and Single-cell environments should be supported with maximum throughput. Look for New Wireless Access Scheme that covers both environments.

8 ©  Roke Manor Research 2002 Roke Manor Research RC/DWS/Japan OFCDMA And the winner is …….. OFCDMA is MC CDMA. If the spreading factor = 1, MC-CDMA  OFDMA. f Spreading and Scrambling Code #1 #2 #C mux SF Code Multiplexing Variable Spreading Factor MC CDMA

9 ©  Roke Manor Research 2002 Roke Manor Research RC/DWS/Japan Smart antennas  Considered “Indispensable”  All labs have active programmes  Trial antenna at KDDI  Status:  Probably lag Europe e.g. NTTDoCoMo array RLS processor

10 ©  Roke Manor Research 2002 Roke Manor Research RC/DWS/Japan MIMO  Multi-element array antenna at both ends of link.  Space-time coding  Highly computationally intensive  Status:  All Japanese R&D labs have a programme  No obvious advance over European knowledge  “USA well ahead of rest of the world” Tx Processing DeMux Encoding, Modulation, Tx Processing DeMux Encoding, Modulation, Rx Processing Demodulation Decoding, Mux, Rx Processing Demodulation Decoding, Mux, MIMO CHANNEL           TRR T NMM N hh hh     Tx Rx

11 ©  Roke Manor Research 2002 Roke Manor Research RC/DWS/Japan Will this achieve 100Mb/s?  No calculation to confirm this yet.  Real transmit power issues  Battery technology  Testbed under construction:  Summer 2002  200m range LoS  100 Mb/s Downlink, 40 Mb/s uplink  Note BLAST work in USA:  spectral efficiency of 20-40bit/s,  But real life?

12 ©  Roke Manor Research 2002 Roke Manor Research RC/DWS/Japan Terminals  3G is here  NTTDoCoMo – FOMA W-CDMA terminals from NEC and Matsushita  KDDI – CDMA 2000 – multiple suppliers

FOMA -Terminals c NTT DoCoMo FOMA N2001/2002 FOMA P2101V /D2101V FOMA P2401 Standard (i-mode)Data Card Visual Voice, 384k Packet/ i-mode, 64k Data, Multi Access 64k Real-time Video, Voice, 384k Packet/ i-mode 384k Packet, 64k Data,

14 ©  Roke Manor Research 2002 Roke Manor Research RC/DWS/Japan KDDI  Pics and projections

15 ©  Roke Manor Research 2002 Roke Manor Research RC/DWS/Japan 4G terminal concepts  Voice recognition  Wearable communicators/computers  Status:  Early days

16 ©  Roke Manor Research 2002 Roke Manor Research RC/DWS/Japan 4G terminal concepts  Voice recognition  Wearable communicators/computers  Status:  Early days

17 ©  Roke Manor Research 2002 Roke Manor Research RC/DWS/Japan Direct conversion  Quoted as necessary for 4G by NTT, KDDI, Fujitsu and Matsushita  Single chip solution  Reduced cost

18 ©  Roke Manor Research 2002 Roke Manor Research RC/DWS/Japan Software Defined Radio  IEICE SDR study group  Considered ‘key’  Unclear strategy for terminals or basestations

19 ©  Roke Manor Research 2002 Roke Manor Research RC/DWS/Japan Summary  100 Mb/s is a target for 4G research  Need new air interface to achieve it.  Not in tune with Europe or USA  If right, Japanese research programme will provide a technical and market lead in next 10 years  If wrong ….

20 ©  Roke Manor Research 2002 Roke Manor Research RC/DWS/Japan