History of the Digital Mobile Radio Systems in NTT & DoCoMo The University of Electro-Communications Nobuo Nakajima
Progress of the Mobile Radio Systems Every 10 years 1 G Analog 2 G Digital 3 G IMT-2000 3.9-4 G LTE,-advanced 5G LTE-advanced? 1979 1992 2001 2010 2020 Access FDMA TDMA CDMA OFDMA, Frequency Scheduling Frequency 800 MHz 2 GHz 3 GHz > 3 GHz millimeter wave Terminal Portable phone Smart phone 2
Frequency Frequency Frequency Access Scheme for 1-4th Generation Time Time FDMA TDMA CDMA Time Frequency Time Frequency Scheduling 3
1 st Generation
1G Development History 1980 1990 2000 1G 2G 3G 79 93 NTT 86 PDC(800M) NTT High Capacty 89 J-TACS by IDO, Cellular 94 PDC(1.5G) 92 NTT DoCoMo started 95 PDC(Half rate) Analog to Digital (Replace) 97 PDC Packet 99 i-mode By PDC-P 98 CDMA by DDI 01 IMT-2000 2.4k FEC 9.6k ARQ 28.8k By 3 time slots 384k 5
Propagation Loss Propagation Loss Estimation - Okumura Hata Curve/Empirical Formula - Base Station Antenna Height Mobile Station Antenna Height Urban Area Distance Free space loss Propagation Loss Frequency
1G Technologies and Specifications Beginning (1979) Last Stage (1986) Frequency 800 MHz Band Access Scheme Applied Technologies Analog FDMA Channel Separation 25 khz 12.5 khz (Interleaving) Smaller Cells Higher Capacity (100,000 Subscriber For Metropolitan Area) Robust Interference reduction Diversity Reception For BS and MS Base Station Beam Tilting AMPS 30 khz
Antenna Diversity Trunk lid Antenna Roof Top Antenna In-room Antenna Sleeve Antenna #1 Whip Antenna Sleeve Antenna #2 Built-in Antenna Trunk lid Diversity Antenna Portable Phone Diversity Antenna
Interference Reduction by Beam Tilting Relative Receiving Level (db) Receiving Level With Tilt Without Tilt Tilting Effect Distance Phase Shifter Without tilt Antenna With tilt Distance Experimental Result 9
Smaller Cells 1995 1979 10
1 st Mobie Terminal 6000cc 10kg 11
Mobile Terminals by NTT 1989 MicrTAC (211 cc) by Motorola 1979 1985 1987 1991 Mova (140 cc) Vehicular Terminal (10,000 cc 10 kg) Shoulder Phone (3 kg) Portable Phone (900 cc, 900 g)
2 nd Generation
2 nd Generation Digital System Purpose: High Capacity, Data Communication Common Interface (Europe) Development in the World USA: FDMA By Motorola, Lucent Ericsson proposed to TIA 3ch TDMA Japan: FDMA By NTT 3 International Standards Europe GSM (Group Special Mobile) Competition (TDMA, CDMA, Frequency Hopping,,,,,) 8chTDMA cdmaone Was added 14
PDC and IS-54(Digital APMS) PDC Access Scheme 3ch TDMA Modulation Pi/4 shift QPSK Channel Separation 25 khz IS-54 30 khz Speech CODEC V-CELP (Motorola) 11.2 kbps CELP 13 kbps Countermeasure For Multipath Fading Mobile Terminal Hardware Tech. PSI-CELP (DoCoMo) 5.6 kbps Antenna Diversity (Both Direction) Single Mode Efficient Linear Amp. (MS) Equalizer Dual Mode Common Power Amplifier (BS)
Reason of 3ch TDMA - Minimum Time Slot Number - TDMA Frame Minimum Bandwidth for Multipath fading Countermeasure Time CONT Transmit Receive Monitor Measure Receiving Levels from Surrounding Base Stations for MAHO (Mobile Assisted Hand Over) 16
Pi/4 shift QPSK Constellation Spectrum
Accumulation Measured Delay Spread Urban Area Basin Area Delay Spread
Feed Forward Ultra Linear Common Power Amplifier (SAFF: Self Adjusting Feed forward) 30 channels, Total 30 W Coupler Pilot Signal Coupler Coupler Main AMP Sub AMP SAFF Detect Distortion Controller Pilot Detection Without SAFF Spectrum
From Massive and Lossy Filter Bank to Common Power Amplifier Power Amplifier Antenna 1G 2G Antenna MODEM MODEM Filter Bank Ultra Liner Power Amplifier MODEM 20
Efficient Liner Power Amplifier For Mobile Terminal Binary Data Envelop MOD DC Amplifier F-Class Amplifier Power Supply Power Efficiency : 40 %
2G Development History 1980 1990 2000 79 93 NTT 86 PDC(800M) Propagation Loss + 6dB 1G 2G 3G NTT High Capacty Soft Decision for Error Correction 89 J-TACS by IDO, Cellular 94 PDC(1.5G) 92 NTT DoCoMo started 95 PDC(Half rate) Analog to Digital (Replace) 97 PDC Packet 99 i-mode By PDC-P 98 CDMA by DDI 01 IMT-2000 Data Speed: 2.4k 9.6k FEC ARQ 28.8k By 3 time slots 384k 22
Relative Loss (db) Propagation Loss versus Frequency 30 20 10 1G 3G 4G 0-10 2G -20 Pager -30 100 M 1 G 2G 3G 5G 8G 10 G Frequency (Hz)
3 rd Generation
3 rd Generation System Purpose: High Speed (2Mbps), New Services Nationwide Unified Standard Development in the World Japan: W-CDMA Europe UMTS USA: Enhancement of cdmaone W-CDMA cdma2000 3 International Standard China: TDD type CDMA TDS-CDMA 25
W-CDMA versus IS-95 W-CDMA (UMTS) IS-95 Access Scheme CDMA Bandwidth 5 MHz 1.25 MHz Base Station Synchronization No By GPS Spreading Code Orthogonal For any spreading factor Orthogonal For same spreading factor
3 rd Generation EV-DO, HSPA
Receiving Level (db) HSPA ( High-Speed Packet Access ) Throughput Best Effort 14.4 Mbps by 5 MHz Bandwidth! User A User B User C Channel Assign Round Robin Maximum CIR Proportional Fair 28
3.9-4 th Generation Unified International Standard By 3GPP
Dominant Access Scheme Maximum Transmission Bitrate LTE versus W-CDMA LTE Packet Down: 100 Mbps Up : 50 Mbps W-CDMA Circuit Switch Down: 14 Mbps Up : 7 Mbps Transmission Delay < 5 msec > 10 msec Bandwidth 1.4M, 3M, 5M, 10M, 15M, 20M 5M only Multiplexing OFDM CDMA Scheduling Every 1 msec No Antenna MIMO, Diversity Diversity
Review for Technological Improvements
Transmission Bitrate Transmission Bitrate 1G >=1G 100M 1M 384k 3.6M 14M 28.8k 1k 2.4k 2G 3G 3.9 4G 5G Guarantee Best Effort 32
Spectrum Efficiency 10kbps 100kbps 1Mbps 10Mbps Guarantee BEST EFFORT From National Broadband Plan (FCC)
Spectrum Efficiency 10 Spectrum Efficiency 1 LTE HSPA 0.1 W-CDMA 0.01 GPRS 1k 1M 1G Transmission bitrate Transmission Bitrate = Spectrum Efficiency 2
Future
Traffic Explosion 2 times / a year 256 times at 2020 Novel ideas and technologies are necessary against such huge traffic demands.
Max Range (m) Cell Size will be Reduced 10k 4k 2k 1k 400 Frequency (GHz) 1 2 3 4 5 64k Output 250mW Fade Margin 5.3dB HSDPA 3.6M HSDPA 7.2M 200 100 100M 1G 40 0 2 10k 1M 100M 10G Transmission Bitrate (Hz) 37
Future Service and Human Interface M2M IoT Entertainment email Portable phone Line Smart phone Wearable Virtual Reality Tele-Existence voice Vehicular phone 1980 2000 2020 38
Thank you for listening and Congratulation for Prof. Adachi s New Life! Nobuo Nakajima 39